Proceedings Book 2019 MVMA Convention by movma

Table of Contents Note: Abstracts received as of 12-15-18. Some speakers will use handouts at their lecture.

Companion Animal Presentations Chris Adolph, DVM, MS

You Will Never Look at Ticks the Same........................................................................................................9 Feline Parasites: It’s More Than Just Fleas..................................................................................................17

Kristen O’Dell-Anderson, DVM, MS, DACVR

Radiography of The Thorax.........................................................................................................................27

Todd Tams, DVM, DACVIM

Diagnosis of Acute and Chronic Vomiting in Dogs and Cats.....................................................................53 Acute and Chronic Diarrhea in Dogs and Cats..........................................................................................63 Diagnosis and Management of Gastric Hypomotility in Dogs ...................................................................79 Inflammatory Bowel Disease and Intestinal Lymphoma In Cats . ..............................................................87 Inflammatory Bowel Disease (Ibd) In Dogs –Diagnosis and Therapy . ....................................................103 Drug Therapy for Vomiting in Dogs and Cats ..........................................................................................117

Leah Cohn, DVM, PhD, DACVIM (SAIM)

Leptospirosis…...........................................................................................................................................127 Feline Infectious Peritonitis.......................................................................................................................133 Tick Transmitted Infections . ....................................................................................................................137

William D. Saxon, DVM, DACVIM, DACVECC

So the SDMA is increased. Now What?...................................................................................................147 Acute Kidney Injury - New Perspectives ..................................................................................................153 Proteinuria: When It Matters and What to Do About It ........................................................................159 Bacteria In the Urine: Always a Bad Thing? ............................................................................................163

Food Animal Presentations Daniel Givens, DVM, PhD, DACT, DACVM

Does Modified-Live Viral Vaccine Administration to Heifers or Cows Lack Substantial Risk?...............171 Review: Risks of Disease Transmission Through Semen In Cattle ..........................................................177

Amelia Woolums, DVM, PhD, DACVIM, DACVM

The Amazing Immune System: Review and Update.................................................................................187 Immunity in Calves and Stockers: What’s the Latest?..............................................................................197 Keys to Effective Vaccination of Calves.....................................................................................................207 Risk Factors for Bovine Respiratory Disease in Preweaning Beef Calves..................................................217

Equine Presentations Elizabeth A. Giuliano, DVM, MS, DACVO

Essentials to the Equine Ophthalmic Examination...................................................................................227 Treatment Modalites for Common Equine Ohphthamic Diseases............................................................233 Equine Ocular/Periocular Neoplasia..........................................................................................................239 What’s Your Ophthalmic Diagnosis And Plan?.........................................................................................245

Tamara Gull, DVM, PhD, DACVIM (LA), DACVPM, DACVM

Molecular Diagnostics in Equine Medicine...............................................................................................249 Antimicrobial Resistance in Equine Disease.............................................................................................261

Martha Scharf, DVM, DAVP

Equine Wounds – Improving Initial Assessment and Field Management.................................................265 Equine Wounds – Techniques for Management of Distal Limb Wounds..................................................273

Science On the Forefront Kevin Cummings, PhD

Respiratory Physiology: A Refresher..........................................................................................................287

Marc Markway, DVM

Use of Class 4 Laser Therapy in an Equine and Small Animal Practice...................................................290

Brandon Ames, CEO

Amnion FAQ: Top 10 Things You Should Know About the Latest in Regenerative Treatments...........301

Wellness and Soft Skills Presentations Tamara Hancock, DVM, MS, PhD and Kerry Karaffa, PhD

Mental Health Experiences and Service Use Among Veterinary Professionals........................................315

Shelia Taylor, DVM

Mental Health First Aid............................................................................................................................325

Brian Patrick, DVM

Building Trust With Clients.......................................................................................................................333

Practice Management Presentations Brian Patrick, DVM

Communication Within the Veterinary Healthcare Team........................................................................347 Making a Clear Recommendation ............................................................................................................353

Andy Roark, MS, DVM

Sharpening Your Axe.................................................................................................................................361 Working With the Cash-Strapped Client..................................................................................................363 How to Drive Change................................................................................................................................365 The Jedi Mind Trick...................................................................................................................................367 Built to Last................................................................................................................................................371

Special Interest Presentations Michael Boeger

Missouri Bureau of Narcotics & Dangerous Drugs...................................................................................379

Carol Ryan, DVM

Standards for Missouri Veterinary Medical Records..................................................................................387

Daniel Shaw, DVM, PhD, DACVP, DACPV

Diseases of Poultry.....................................................................................................................................399

MU-CVM 25-Minute Talks Brian Flesner, DVM, MS, DACVIM (Oncology)

Novel Treatments and Trials......................................................................................................................419

Amy DeClue, DVM, MS, DACVIM (SAIM)

Clinical Updates on HPA Axis Disorders..................................................................................................435

Derek B. Fox, DVM, PhD, DACVS

Current Treatment Strategies for Canine Hip Dysplasia...........................................................................441

Karen Campbell, DVM, DACVIM, DACVD

Topical Therapy for Dogs With Methicillin-Resistant Staphylococcal Infections....................................445

Daniel Shaw, DVM, PhD, DACVP, DACPV

Diagnosis of Cattle Found Dead................................................................................................................453

Alison LaCarrubba, DVM, DABVP

Equine Gastric Ulcer Syndrome: Current Thoughts on Risk Factors and Therapy.................................461

Lab/Lecture Presentation Keith Branson, DVM, MS, DACVAA

Blood Pressure Monitoring........................................................................................................................473 Capnography..............................................................................................................................................475

Companion Animal

Chris Adolph, DVM, MS

Affiliate, National Center for Veterinary Parasitology Oklahoma State University Stillwater, Oklahoma

10/31/2018

Text questions any time during the presentation: 918-600-7338 You Will Never Look at Ticks The Same Dr. Chris Adolph DVM, MS, Dipl ACVM (Parasitology) Senior Veterinary Specialist, Zoetis

TICKS ARE NOT FLEAS Ticks • Class: Arachnida • Head, Thorax, and abdomen fused • 8 jointed legs as adults • Simple metamorphosis (Hemimetabolous) • Prefers up to 3 hosts • Spends majority of life off host

Fleas • Class: Insecta • Head, Thorax and Abdomen distinct • 6 jointed legs as adults • Complex metamorphosis (Holometabolous) • Prefers to stay on 1 host • Obligate parasites

TICKS ARE NOT EVEN TICKS • Differences between species – Distribution – Habitat – Host preference – Seasonal occurrence – Longevity – Diseases vectored

GENERAL CHARACTERISTICS •

Ticks find hosts by CO2 detection and questing

•

Ticks attach to host by ambush or hunting up to several meters

•

Tick saliva has anti-inflammatory, anti-coagulatory, and anesthetic properties

•

Ixodidae ticks secrete cementum to assist attachment

•

Slow feeders, several days to engorge

•

Salivary glands primary site for excreting excess water and transmission of pathogens

•

Once feeding is complete, secreted enzymes digest cement to detach

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Text questions any time during the presentation: 918-600-7338

AMBLYOMMA SPP.

Amblyomma americanum DISTRIBUTION • Central Texas to Florida • North to NY, NJ, and Maine • West to Michigan • South through central KS, OK, and Texas ASSOCIATED DISEASES • Ehrlichiosis

Ehrlichiosis Incidence, 2010

– Ehrlichia chaffeensis – Ehrlichia ewingii

• Tularemia – Francisella tularensis

• Rocky Mountain Spotted Fever – Rickettsia rickettsi

• Cytauxzoonosis – Cytauxzoon felis

Amblyomma maculatum •

Distribution – Historically only in SE states close to the Gulf of Mexico – Now in OK, KS, and AR – As far north as MD and DE

•

Associated diseases – Canine hepatozoonosis • Hepatozoon americanum – Rickettsia parkeri • Rickettsial disease of people – Tick paralysis

A. maculatum in weird places?

Image courtesy of Desiree Leone

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DERMACENTOR SPP.

Dermacentor variabilis

IXODES SPP.

DISTRIBUTION • Eastern US FL to New England, from the Atlantic coast to the planes states • Populations also on the Pacific coast ASSOCIATED DISEASES

• Major vector of Rocky Mountain Spotted Fever – Rickettsia rickettsi

• Cytauxzoonosis – Cytauxzoon felis

• Tularemia – Francisella tularensis

• Tick Paralysis

Ixodes scapularis

RHIPICEPHALUS SANGUINEUS

DISTRIBUTION  Maine to Florida, West to Central Texas and North to Minnesota ASSOCIATED DISEASES • Lyme disease – Borrelia burgdorferi

• Human Granulocytic Ehrlichiosis – Anaplasma phagocytophilum

• Human babesiosis – Babesia microti

• Ehrlichiosis – Ehrlichia muris like agent

• Tick-Borne relapsing fever – Borrelia miyamotoi

• Tick paralysis

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Rhipicephalus sanguineus •

Distribution: Throughout North America and Hawaii

•

Associated diseases – Canine Monocytic Ehrlichiosis • Ehrlichia canis – Canine Babesiosis • Babesia canis • Babesia gibsoni – Anaplasmosis • Anaplasma platys – RMSF • Rickettsia rickettsii

• •

The Cattle Tick or Brush Tick or Scrub Tick Found in Australia, New Zealand, China, Japan, Western Pacific Rim, and several Pacific Islands

•

Preferred hosts include cattle

HAEMAPHYSALIS SPP.

Haemaphysalis longicornis

– Will also feed on horses, deer or sheep – May feed on dogs, cats and humans

•

Associated diseases include – Babesia gibsoni – Anaplasma phagocytophilum

Until Something Better Comes Along

Text questions any time during presentation: 918-600-7338

https://tickencounter.org/

https://www.showusyourticks.org/

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COMMON CLIENT OBJECTIONS We don’t have ticks where I live Why don’t I see them? We don’t have trees We only stay on the trail Ticks die off in the winter

 Show them the maps     

Go back to lifecycle basics Not fleas; short time on host Pre-adult stages very small Ticks quest at host level They don’t drop from trees

ASSOCIATED PATHOGENS

 Dermacentor spp. are abundant  Ixodes spp. adults most active Oct–Feb

Tick-borne Disease Timeline1,2 Transmission Time

Seropositive

B. burgdorferi

Anaplasma & Ehrlichia 0

Anaplasma & Ehrlichia A E 72

Hours Post-attachment

Weeks Post-attachment B. burgdorferi

Anaplasma & Ehrlichia

Clinical Signs 1. Kidd & Breitschwerdt, 2003. Compendium 25 (10):742-751. 2. Little, S. 2009. https://idexxlearningcenter.idexx.com/idexx/resources/library/media_edu/archived_webinars/faqs/ Anaplasmosis_and_Ehrlichiosis_Webinar_FAQs.pdf (accessed 1/12/17)

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Ixodes scapularis (black-legged/deer tick)

Text questions any time during the presentation: 918-600-7338

STUDY DESIGN

3 GROUPS OF 8 DOGS EACH Group 1 Placebo Given Day 0 and 7

Group 2 Sarolaner Given Day 0

Group 3 Sarolaner Given Day 7

 Adult ticks were obtained from Rhode Island  PCR prior to infestation (tick infectivity): – 57% were positive for B. burgdorferi – 6.7% were positive for A. phagocytophilum

 Each dog was infested with 50 (±5) I. scapularis ticks on Day 28. – Day 29 – Tick counts without removal were performed (24 ± 2 hrs after infestation) – Day 30 – Tick counts without removal were performed (48 ± 2 hrs after infestation) – Day 33 – Tick count and removal

 Blood was collected on Days -6, 27, 49, 63, 77, 91, and 104  Skin biopsy was performed on Day 104 Hornsberger N et al, Efficacy of sarolaner in the prevention of Borrelia burgdorferi and Anaplasma phagocytophilum transmission from infected Ixodes scapularis to dogs; Veterinary Parasitology Volume 222, 30 May 2016, Pages 67–72

Efficacy of sarolaner in the prevention of Anaplasma phagocytophilum and transmission from infected Ixodes scapularis to dogs

Efficacy of sarolaner in the prevention of Borrelia burgdorferi and transmission from infected Ixodes scapularis to dogs

Prevention of A. phagocytophilum transmission

Prevention of Borrelia burgdorferi transmission Treatment Group

Day of Treatment

Day of Tick infestation

Antibody

7 of 8 (87.5%)

PCR

Culture

Treatment Group

Day of Treatment

Day of Tick infestation

Antibody

Placebo

0 and 7

4 of 8 (50%)

Placebo

0 and 7

6 of 8 (75%)

Sarolaner

0 of 8 (0%)

Sarolaner

0 of 8 (0%)

Sarolaner

0 of 8 (0%)

Sarolaner

0 of 8 (0%)

The number of dogs ‘ever positive’ for B. burgdorferi was significantly different than the placebo group (P=0.0002) Hornsberger N et al, Efficacy of sarolaner in the prevention of Borrelia burgdorferi and Anaplasma phagocytophilum transmission from infected Ixodes scapularis to dogs; Veterinary Parasitology Volume 222, 30 May 2016, Pages 67–72

Although not statistically significant (P=0.0769), none of the sarolaner-treated dogs were ‘ever positive’ for A. phagocytophilum, indicating 100% prevention of A. phagocytophilum transmission v

Hornsberger N et al, Efficacy of sarolaner in the prevention of Borrelia burgdorferi and Anaplasma phagocytophilum transmission from infected Ixodes scapularis to dogs; Veterinary Parasitology Volume 222, 30 May 2016, Pages 67–72

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•

Experimental infection with wild caught Ixodes scapularis – Single dose of Nexgard® prevented transmission of B. burgdorferi from ticks to dogs infested at Day 28 Negative antibody results; PCR and culture not performed – Transmission of Anaplasma phagoctyophilum – Data not reported but SNAP 4Dx Plus® test used

BUT I WANT A SCRIPT FOR MY MEDS •

ABSOLUTELY!!!!

•

We want Rex to be protected year round

•

Injectable HW prevention q6 months

•

Recommending FDA approved flea and tick meds at least starts this conversation

•

If you need to save $2/month we will help you

•

We will write you a script

•

I lost <3% of my total doses this way and maintained a happy (for the most part) client base

– EPA meds are available without a DVM in the loop

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TODAY’S DISCUSSION TOPICS Introduction-Are Cats Underserved? Current State of Our Knowledge

Feline Parasites; It’s More Than Just Fleas

 Cat flea biology  Feline heartworm disease  Feline intestinal parasites

Chris Adolph, DVM, MS, Diplomate ACVM (Parasitology) 1|

CATS ARE UNDERSERVED COMPARED TO DOGS DOGS

CATS

Total Number in United States

69.9M

74.1M

Number of Households Owning

43.3M

36.1M

Percent of Households Owning

36.5%

30.4%

Average Number Owned per Household

1.6

2.1

Veterinary Visits per Household Per Year (Mean)

2.6

1.6

Veterinary Expenditure per Household per Year (Mean)

$378

$191

Veterinary Expenditure per Animal (Mean)

$227

$90

CAT FLEA BIOLOGY

https://www.avma.org/KB/Resources/Statistics/Pages/Market-research-statistics-US-pet-ownership.aspx 3|

FLEA LIFE CYCLE

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HEARTWORMS AND INTESTINAL PARASITES

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VECTOR-BORNE INFECTIONS

GI NEMATODES

 Flea are common on cats  Although often under recognized, vector-borne agents can be an important cause of feline disease and/or potential zoonosis

– Dirofilaria immitis 2.1%-4.9%1,2

 Toxocara cati most common internal parasite of cats worldwide – 21.0%-36.2%1,2

 Ancylostoma tubaeforme is also common

– Bartonella henselae 5.0%-90%3,4

– 4.4%-75%3,4

* Photos courtesy of the NCVP 1. Carleton R. and Tolbert M., 2004. Vet Parasit 119, 319–326. 2. Atkins C., DeFrancesco T. and Coats J., 2000. JAVMA 217, 355–358. 3. Heller R., et al., 1997. Journal of Clinical Microbiology 35, 1327–1331. 4. Nutter F., et al., 2004. JAVMA 225, 1394–1398. 13 |

Photos courtesy of the NCVP 1. Lucio-Foster A. and Bowman D., 2010. Journal of Feline Medicine and Surgery 13, 300–303. 2. Lillis W., 1967. Journal of Parasitology 53, 1082–1084. 3. Amin O., 1980. Wisconsin Academy of Sciences, Arts, and Letters 68, 106–110. 4. Anderson T., Foster G., and Forrester D., 2003. Veterinary Parasitology 115, 19–24. 14 |

GI CESTODES  Cestode infection is also common – 10.4%-13% D. caninum1,2 – 22.0%-33.0% Taenia spp.2,1

FELINE HEARTWORM  Dirofilaria immitis / mosquito  Seroprevalence rates vary by survey and assay

 Historically surveys have reported fecal flotation analysis

– Antibody tests: 2.1-17%1,2 – Antigen tests: 0.9-8%3,4

– Underestimates true prevalence – Nonetheless suggests infection common in pet cats

 Can be associated with acute or chronic respiratory signs and /

or sudden death in cats

 Other species also seen

Photo courtesy of the NCVP 1. Hermesmeyer M., Limberg-Child R., Murphy A., et al., 2000. JAVMA 217, 211–212. 2. Levy J., Snyder P., and Taveres L., 2003. JAAHA 39, 533–537 3. Lorentzen L. and Caola A., 2008. Veterinary Parasitology 158, 183–190. 4. Levy J., Lappin M., Glaser A., et al., 2011. JAVMA 238, 311–317.

Photos courtesy of the NCVP 1. Lillis W., 1967. Helminth survey of dogs and cats in New Jersey. Journal of Parasitology 52, 1082-1084. 2. Amin O., 1980. Helminth and arthropod parasites of some domestic animals in Wisconsin. Wisconsin Academy of Sciences, Arts, and Letters 68, 106-110 15 |

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LIFE CYCLE OF TOXOCARA CATI Host ingests PH with larvae arrested in tissue Host ingests infective eggs with larvae Larvae may be shed in milk and ingested by neonates

Adult ascarids in small intestine

Eggs pass in feces and larvate

Photos courtesy of the NCVP 17 |

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LIFE CYCLE OF ANCYLOSTOMA TUBAEFORME

DIPYLIDIUM CANINUM: LIFE CYCLE

Adult hookworms in small intestine

Host ingests PH with larvae arrested in tissue

Cysticercoid in ingested flea develop into adults in the small intestine

Proglottids containing egg packets pass in feces

Develop into infective cysticercoids in the developing flea

Ingested by flea larvae

Host ingests infective larvae

Larvae penetrate skin of host Eggs pass in feces and larvate

Photos courtesy of the NCVP 19 |

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TAENIA TAENIAEFORMIS: LIFE CYCLE Cat infected by eating intermediate host

Tapeworm proglottids containing infective eggs pass in feces

FELINE PARASITE PREVALENCE STUDY1  Determine prevalence of past or current vector borne disease agents including –

Dirofilaria immitis

–

Bartonella henselae

 Determine the prevalence of intestinal parasites including

Develop into infective cysticercoids in the developing flea

–

Toxocara cati

–

Ancylostoma tubaeforme

–

Physaloptera spp.

–

Cestodes

 Determine the utility of common diagnostics

Eggs released from proglottids into environment

Rodent intermediate host ingests eggs 21 |

 Determine risk factors for acquiring these parasites 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 22 |

MATERIALS AND METHODS1

MATERIALS AND METHODS1 (CONT.)

 116 adult cats examined

 Helminths rinsed in PBS and fixed in Beltsville solution for identification and enumeration at Oklahoma State University

 Cats examined externally for ectoparasites  Body condition score (BCS) 1-9, and age estimated

 Statistical analysis performed to evaluate association of presence of each helminth infection with;

 Feces collected and evaluated by centrifugation with sugar solution (SG=1.27) and passively with sodium nitrate (SG=1.25)

– – – –

 Blood and serum collected for vector-borne disease analysis  Gl tract examined at necropsy, helminths collected

* Photo courtesy of the NCVP 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 23 |

Estimated age category BCS Fecal flotation results Co-infection with other helminths

Photo courtesy of the NCVP 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 24 |

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MATERIALS AND METHODS1 (CONT.)

RESULTS1

 Dirofilaria immitis

 Average age: 2.7 years old (Range 1-12)

– Antigen: ELISA: Feline Triple SNAP; 4DxSNAP; PetChek (spec.)

 Average BCS: 4.7 (Range 3-9)

– Antigen: Post heat treatment w/ diroCHEK (Zoetis)

 Fleas recovered from 85/116 cats (73.3%)

– Antibody: IDEXX in-house assay – Necropsy evaluation of cardiopulmonary tract

• Others had flea dirt or evidence of flea allergy dermatitis • All fleas recovered were Ctenocephalides felis

 Bartonella henselae – IFA (commercial slides from Fuller Laboratory)

Photo courtesy of the NCVP 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 25 |

Photo courtesy of the NCVP 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 26 |

RESULTS: VECTOR-BORNE DISEASES1,2

EVIDENCE OF PATHOLOGY: NEMATODE MIGRATION1

 Dirofilaria immitis  50/116 (43.1%) of cats with lung lesions consistent with nematode migration

– No adult heartworm found at necropsy – Antibody: 10/116 (8.6%) – Antigen: Pre-Heat Treatment 0/116 (3 methods)

– Not significantly associated with presence of T. cati in the small intestine

– Antigen: Post-Heat Treatment 9/116 (DiroCHEK, Zoetis)

– Not significantly associated with HW Ab serology – Association of post-heat treated Ag positive cats and moderate/severe lung lesions

 Bartonella henselae

 Medial hypertrophy of pulmonary arterioles: Older lesions/resolved infection

– IFA: 93/116 (80.2%) positive at 1:64 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 2. Little S., Gruntmier J., Adolph C., Blagburn B., 2014. Prevalence of Dirofilaria immitis antigen in feline samples after heat treatment. Abstract, 59 th American Association of Veterinary Parasitologists Annual Meeting, Denver, CO. 27 |

1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 28 |

REFERENCE

Bronchiole

Arteriole Photo courtesy of the NCVP

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RESULTS1 (CONT.)

RESULTS (CONT.)

 Ascarids in 48/116 (41.4%)  Hookworms in 8/116 (6.9%)

 Cestodes in 63/116 (54.3%) cats – Dipylidium caninum: 40/116 (34.5%)

 Physaloptera in 3/116 (2.6%)

– Taenia taeniaeformis: 30/116 (25.9%) – Co-infection with both: 7/116 (6.0%)

Photos courtesy of the NCVP 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 31 |

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RESULTS: DIAGNOSTIC TESTS1

RESULTS: DIAGNOSTIC TESTS (CONT.)

 T. cati – Centrifugation: 37/48 (77.1%)

 T. taeniaeformis

– Passive: 33/48 (68.8%)

– Centrifugation: 8/30 (26.7%) – Passive: 3/30 (10%)

 A. tubaeforme

– Proglottids identified: 6/30 (20%)

– Centrifugation 8/8 (100%) – Passive 2/8 (25%)

 D. caninum

 Physaloptera

– Centrifugation: 0/40 (0%)

– Both methods 0/3 (0%)

– Passive: 0/40 (0%)

Photos courtesy of the NCVP 1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 33 |

– Proglottids identified: 6/40 (15%) 34 |

Intensity: Helminths

RESULTS1 (CONT.)

 T. cati B. HENSELAE X FLEAS

TAENIA X TOXOCARA CATI

POST-HEAT TREATED D. IMMITIS AG X MODERATE/SEVERE LUNG SCORE

P < 0.001

P = 0.001

P=0.028

– 7.2 (1-35)

 D. caninum – 10.3 (1-63) – 5 cats have over 20 adult D. caninum

 T. taeniaeformis – 12.5 (1-56) – 5 cats had over 35 adult T. taeniaeformis – Cestode mass in 1 cat weighed 34.4 grams (1.5% of cat’s body weight) 35 |

30 cats were T. teaniaeformis positive. 82.3% of cats with fleas were positive for B. henselae Of those, 20 were T. cati positive

3 cats with moderate/severe lung scores were initially Agand converted to Ag+ after heat treating the sample

1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 36 |

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CONCLUSIONS1

 Ascarids (T. cati) very common in cats in this study  Detection techniques failed to identify infections in some cats with T. cati – Improved diagnostic techniques may allow detection of infections currently overlooked

 Fleas are common ectoparasites of cats, but ticks also found – Supports importance of routine heartworm and flea prevention for cats

 This study also demonstrated evidence of past or current infection with B. henselae and D. immitis  Feral cats likely commonly harbor these infections

 Veterinarians should recognize that parasitic infections are more common in cats than current diagnostic tests  Treatment with appropriate anthelmintic may be indicated when history suggests likely infection, regardless of results of fecal diagnostic test  Prophylactic use of anthelmintics and insecticides may be necessary to prevent infections

1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 37 |

1. Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vector-borne infections of cats in NE Oklahoma. Master’s Thesis 38 |

PLEASE CONTACT ME WITH ADDITIONAL QUESTIONS

chris.adolph@zoetis.com

REFERENCES 1.

Adolph C., 2013. Prevalence, disease implications, and diagnostic assays for parasites and vectorborne infections of cats in NE Oklahoma. Master’s Thesis

American Animal Hospital Association-American Veterinary Medical Association Preventive Healthcare Guidelines Task Force and The American Animal Hospital Association-American Veterinary Medical Association Preventive Healthcare Guidelines Task Force, 2011. Journal of the American Animal Hospital Association 47, 306 – 311.

Amin O., 1980. Helminth and arthropod parasites of same domestic animals in Wisconsin. Wisconsin Academy of Sciences, Arts, and Letters 68, 106–110.

Anderson T., Foster G., and Forrester D., 2003. Hookworms of feral cats in Florida. Veterinary Parasitology 115, 19–24.

Atkins C., DeFrancesco T. and Coats J., 2000. Heartworm infection in cats: 50 cases (1985–1997). Journal of the American Veterinary Medical Association 217, 355–358.

Carleton R. and Tolbert M., 2004. Prevalence of Dirofilaria immitis and gastrointestinal helminths in cats euthanized at animal control agencies in northwest Georgia. Veterinary Parasitology 119, 319– 326.

918-600-7338

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Chomel B. and Sun B., 2011. Zoonosis in the bedroom. Emerging Infectious Diseases 17, 167–172

REFERENCES (CONT.)

16. Lorentzen L. and Caola A., 2008. Incidence of positive heartworm antibody and antigen tests at IDEXX Laboratories: trends and potential impact on feline heartworm awareness and prevention. Veterinary Parasitology 158, 183–190.

Dryden M., Smith V., Payne P., McTier T., 2005. Comparative speed of kill of selamectin, imidacloprid, and fipronil-(S)-methoprene spot-on formulations against fleas on cats. Veterinary Therapeutics 6(3), 229-236

10. Heller R., Artois M., Xemar V., et al., 1997. Prevalence of Bartonella henselae and Bartonella clarridgeiae in stray cats. Journal of Clinical Microbiology 35, 1327–1331. 11. Hermesmeyer M., Limberg-Child R., Murphy A., et al., 2000. Prevalence of Dirofilaria immitis among shelter cats. Journal of the American Veterinary Medical Association 217, 211–212. 12. Levy J., Lappin M., Glaser A., et al., 2011. Prevalence of infectious diseases in cats and dogs rescued following Hurricane Katrina. Journal of the American Veterinary Medical Association 238, 311–317.

13. Levy J., Snyder P., and Taveres L., 2003. Prevalence and risk factors for heartworm infection in cats in northern Florida. Journal of the American Animal Hospital Association 39, 533–537. 14. Lillis W., 1967. Helminth survey of dogs and cats in New Jersey. Journal of Parasitology 53, 1082– 1084. 15. Little S., Gruntmier J., Adolph C., Blagburn B., 2014. Prevalence of Dirofilaria immitis antigen in feline samples after heat treatment. Abstract, 59th American Association of Veterinary Parasitologists Annual Meeting, Denver, CO.

41 |

17. Lucio-Foster A. and Bowman D., 2010. Prevalence of fecal-borne parasites detected by centrifugal flotation in feline samples from two shelters in upstate New York. Journal of Feline Medicine and Surgery 13, 300–303. 18. Lue T., Pantenburg D., and Crawford P., 2008. Impact of the owner-pet and client-veterinarian bond on the care that pets receive. Journal of the American Veterinary Medical Association 232, 531–540. 19. McCoy C., Broce A., and Dryden M., 2008. Flea blood feeding patterns in cats treated with oral nitenpyram and topical insecticides imidacloprid, fipronil, and selamectin. Veterinary Parasitology 156, 293-301

20. Nutter F., Dubey J., Levine J., et al., 2004. Seroprevalence of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp., Giardia spp., and Toxocara cati in feral and pet domestic 21. Parsons, J., 1987. Ascarid infections of cats and dogs. Veterinary Clinics of North America, Small Animal Practice 17, 1307–1339.

42 |

Companion Animal

Kristen Oâ&#x20AC;&#x2122;Dell-Anderson, DVM, MS, DACVR Veterinary Specialty Services St. Louis, Missouri

RADIOGRAPHY OF THE THORAX KRISTEN O’DELL, DVM, MS, DACVR VETERINARY SPECIALTY SERVICES

INDICATIONS FOR TAKING RADIOGRAPHS • • • • •

CONFIRM SUSPECTED CLINICAL DISEASE DETERMINE EXTENT OF DISEASE EVALUATE FOR METASTASIS MONITOR RESPONSE TO TREATMENT SCREENING– MEDICAL VS. SURGICAL

PATIENT PREPARATION

• • • •

REMOVE EXTERNAL DEBRIS FROM THORAX AND ABDOMEN GI TRACT – EMPTY URINARY BLADDER – EMPTY WITH AN ACUTE THORAX/ABDOMEN, IDEAL PREPARATION MAY NOT ALWAYS BE POSSIBLE

THORAX - TECHNIQUE & POSITIONING • • • • • •

BOTH LATERALS AND EITHER VD OR DV RADIOGRAPHS THORACIC INLET TO A FEW CM CAUDAL TO THE LAST RIB MEASURE THE THICKEST PART EXPOSURE DURING PEAK INSPIRATION USE GRID HIGH KVP AND LOW MAS FOR LONG SCALE CONTRAST (MANY SHADES OF GRAY)

THE â&#x20AC;&#x153;UPâ&#x20AC;? LUNG

Images retrieved from https://www.veterinaryteambrief.com/article/image-gallery-positioningabdominal-radiographs & Thrall: Textbook of Veterinary Diagnostic Radiology, 6th Edition

Dorsoventral - DV

Ventrodorsal - VD

STANDARD VIEWS

NORMAL CAT

GRIDS SCATTER RADIATION COMES INTO THE DETECTOR FROM ALL DIRECTIONS. RESULT IS A UNIFORM BACKGROUND “FOG” THAT REDUCES THE DYNAMIC RANGE OF THE DETECTOR (DECREASES CONTRAST) GENERAL RULE – ANY ANATOMICAL PART THAT MEASURES 10CM OR GREATER SHOULD BE IMAGED WITH A GRID. ANY TECHNIQUE USING 70 KVP OR HIGHER SHOULD USE A GRID.

EVALUATION OF RADIOGRAPHS

• • • • •

NORMAL ANATOMY NORMAL SIZE NORMAL SHAPE NORMAL LOCATION NORMAL OPACITY

EVALUATION OF RADIOGRAPHS • THERE ARE 5 RADIOGRAPHIC OPACITIES: • AIR •

THORAX HAS AN INHERENTLY HIGH CONTRAST BECAUSE OF THE LARGE VOLUME OF AIR IN LUNGS

• FAT •

FAT GIVES ABDOMINAL CONTRAST AND ALLOWS VISUALIZATION OF SOFT TISSUE ORGANS

• SOFT TISSUE/FLUID • BONE • METAL

EVALUATION OF THORACIC RADIOGRAPHS

• TECHNIQUE AND POSITIONING • EXTRA-THORACIC STRUCTURES • SOFT TISSUES • SKELETAL STRUCTURES • CRANIAL ABDOMEN • DIAPHRAGM

LEFT

RIGHT

Images retrieved from https://veteriankey.com/the-diaphragm/

EVALUATION OF THORACIC RADIOGRAPHS • TECHNIQUE AND POSITIONING • EXTRA-THORACIC STRUCTURES

• THORACIC STRUCTURES • PLEURAL SPACE • MEDIASTINUM • HEART • PULMONARY VESSELS • LUNGS

PLEURAL SPACE THE TINY AREA BETWEEN TWO LAYERS OF THE PLEURA (THE THIN COVERING THAT PROTECTS AND CUSHIONS THE LUNGS) BETWEEN LUNGS AND CHEST CAVITY. THE PLEURAL SPACE IS NORMALLY FILLED WITH A SMALL AMOUNT OF FLUID FOR LUBRICATION.

Images retrieved from https://www.vin.com/veterinarypartner/default.aspx?pid=19239&catId=102899&id=4952287

PNEUMOTHORAX RETRACTION OF PLEURAL SURFACE OF

LUNG AWAY FROM PLEURAL SURFACE OF THORACIC WALL

LUNG MARKINGS DO NOT EXTEND TO THORACIC WALL

FOCAL AIR COLLECTION AROUND CARDIAC APEX IN LATERAL VIEW

APPEARANCE OF DORSAL DISPLACEMENT OF THE HEART ON LATERAL VIEW

SIGNS OF PLEURAL EFFUSION WIDENED INTERLOBAR FISSURES RETRACTION OF THE PLEURAL SURFACE OF LUNG FROM THE BODY WALL

SCALLOPED VENTRAL MARGINS

DECREASED CARDIAC SILHOUETTE VISUALIZATION

OBSCURED DIAPHRAGMATIC OUTLINE

MEDIASTINUM OF ALL THE MEDIASTINAL STRUCTURES (25) ONLY THE FOLLOWING ARE

NORMALLY VISIBLE ON RADIOGRAPHS

TRACHEA

HEART CAUDAL VENA CAVA AORTA THYMUS (JUVENILES) ESOPHAGUS (OCCASIONALLY)

PNEUMOMEDIASTINUM

Image retrieved from https://www.cliniciansbrief.com/article /postintubation-tracheal-tears-cats

MEDIASTINAL MASSES

CRANIOVENTRAL STERNAL LYMPHADENOPATHY CRANIAL MEDIASTINAL LYMPHADENOPATHY

THYMOMA MEDIASTINAL CYST IN CATS ECTOPIC THYROID

MEDIASTINAL ABSCESS

MEDIASTINAL MASSES DORSAL ENLARGEMENT OF THE ESOPHAGUS MEGAESOPHAGUS VASCULAR RING ANOMALY ESOPHAGEAL MASS OR FOREIGN BODY

PARASPINAL TUMOR NEUROGENIC TUMOR MEDIASTINAL DIAPHRAGMATIC HERNIA HIATAL HERNIA

SPIROCERCA LUPI

MEDIASTINAL MASSES

HILAR REGION TRACHEOBRONCHIAL LYMPHADENOPATHY

HEART BASE MASS

MID-ESOPHAGEAL FOREIGN BODY

EVALUATION OF THORACIC RADIOGRAPHS • TECHNIQUE AND POSITIONING • EXTRA-THORACIC STRUCTURES

• THORACIC STRUCTURES • PLEURAL SPACE • MEDIASTINUM • HEART • PULMONARY VESSELS • LUNGS

VERTEBRAL HEART SCORE Normal Range 8.7-10.7 vertebral body lengths beginning at T4 VHS+ 4.3v + 5.9v = 10.2v T4

NORMAL DOG – CARDIAC CHAMBERS

CrVC

LPA

RPA CdVC

RA LA

Slide Courtesy of Dr. DC Brochtrup

NORMAL DOG – CARDIAC CHAMBERS Ao

RA RV

LA LV

Slide Courtesy of Dr. DC Brochtrup

Journal of Veterinary Cardiology Volume 17, Supplement 1, December 2015, Pages S87-S101

PULMONARY VESSELS

MAIN PULMONARY ARTERY ENLARGEMENT PULMONARY HYPERTENSION

HEARTWORM INFECTION

TURBULENCE FROM PULMONIC STENOSIS OR PATENT DUCTUS ARTERIOSUS

PERIPHERAL PULMONARY VESSELS ON LATERAL PROJECTIONS– CRANIAL ARTERIES ARE DORSAL AND VEINS ARE VENTRAL TO THE BRONCHUS

PERIPHERAL PULMONARY VESSELS

ON VD & DV PROJECTIONS– CAUDAL ARTERIES ARE LATERAL AND VEINS ARE MEDIAL TO THE BRONCHUS

CAUDAL PULMONARY VESSELS Dorsoventral Ventrodorsal

CONDITIONS THAT MAY INCREASE THE SIZE OF BOTH ARTERIES AND VEINS

• LEFT TO RIGHT SHUNTS •

PDA, VSD, ASD

• IATROGENIC FLUID OVERLOAD • FLUID RETENTION SECONDARY TO DECREASED CARDIAC OUTPUT

• PERIPHERAL ARTERIOVENOUS FISTULA

CONDITIONS THAT MAY INCREASE THE SIZE OF ARTERIES WITHOUT VENOUS ENLARGEMENT

• HEARTWORM • PRIMARY THROMBOEMBOLIC DISEASE •

HEARTWORM, RENAL DISEASE (AMYLOIDOSIS), SEPTICEMIA, PANCREATITIS, HYPERADRENOCORTICISM

• SEVERE CHRONIC LUNG DISEASE •

PULMONARY HYPERTENSION

CONDITIONS THAT MAY INCREASE THE SIZE OF VEINS WITHOUT ARTERIAL ENLARGEMENT • VOLUME OR PRESSURE OVERLOAD •

MITRAL VALVE INSUFFICIENCY, EARLY LEFT-TORIGHT SHUNT

• PRIMARY MYOCARDIAL DISEASE •

MYOCARDIAL FAILURE, DILATED CARDIOMYOPATHY, HYPERTROPHIC CARDIOMYOPATHY, RESTRICTIVE CARDIOMYOPATHY

CONDITIONS THAT MAY DECREASE THE SIZE OF BOTH ARTERIES AND VEINS • HYPOVOLEMIA •

SHOCK, DEHYDRATION

• RIGHT-TO-LEFT SHUNTS •

TETRALOGY OF FALLOT, VSD WITH PULMONIC STENOSIS

• SEVERE PULMONIC STENOSIS WITH

DECREASED

CARDIAC OUTPUT

EVALUATION OF THORACIC RADIOGRAPHS • TECHNIQUE AND POSITIONING • EXTRA-THORACIC STRUCTURES

• THORACIC STRUCTURES • PLEURAL SPACE • MEDIASTINUM • HEART • PULMONARY VESSELS • LUNGS

LUNG PATTERNS

IDIOT’S GUIDE TO DESCRIBING LUNG PATTERNS • LUNGS - MORE OR LESS OPAQUE? • NAME THE PATTERN • BRONCHIAL • ALVEOLAR • INTERSTITIAL

• +/- VASCULAR

• DISTRIBUTION • DIFFUSE OR FOCAL

• LOCATION • VENTRAL, HILAR, DORSOCAUDAL

LUNG PATTERNS

DECREASED OPACITY

DIFFUSE •

HYPERINFLATION

FOCAL

CAVITARY NODULE BULLA

BRONCHIAL CHRONIC LOWER AIRWAY DISEASE •

ALLERGIC

•

INFECTIOUS

•

PARASITIC

•

(AGE-RELATED MINERALIZATION)

PERIBRONCHIAL

https://www.mspca.org/angell_services/radiographic-approach-to-thecoughing-pet/

INTERSTITIAL RULE OUTS

•

CARDIOGENIC OR NONCARDIOGENIC PULMONARY EDEMA

•

PNEUMONIA

•

HEMORRHAGE

•

NEOPLASIA (LYMPHOMA)

•

PULMONARY FIBROSIS

•

ATELECTASIS

ALVEOLAR RULE OUTS •

CARDIOGENIC OR NONCARDIOGENIC PULMONARY EDEMA

•

BRONCHOPNEUMONIA

•

HEMORRHAGE

•

NEOPLASIA

•

ATELECTASIS

DISTRIBUTION

•

CRANIOVENTRAL

•

CAUDODORSAL

•

PERIHILAR

•

MULTIFOCAL

Companion Animal

Todd Tams, DVM, DACVIM Chief Medical Officer - VCA, Inc. Los Angeles, California

Diagnosis of Acute and Chronic Vomiting in Dogs and Cats Todd R. Tams, DVM, DAVCIM Chief Medical Officer VCA Vomiting is among the most common reasons that dogs and cats are presented for evaluation. Because there are a multitude of causes of vomiting, ranging from simple to complex, this can be a challenging problem for clinicians to accurately diagnose and manage. The problem also causes significant concern for pet owners, especially when there is an onset of frequent severe vomiting or when the occurrence becomes more chronic and intermittent without adequate control. However, by following a systematic approach beginning with an accurate history, a thorough physical exam, and appropriate baseline testing (Stage 1), then performing tests more specific for certain conditions or organ systems (e.g., bile acids assay, leptospirosis serology, baseline cortisol or ACTH stimulation, ultrasonography) (Stage 2), and finally where indicated performing advanced procedures for more thorough examination and biopsy or definitive therapy (endoscopy, exploratory laparotomy), most cases can be diagnosed successfully and managed judiciously. Vomiting does not constitute a diagnosis in itself. It is emphasized that vomiting is simply a clinical sign of any of a number of disorders that can involve any organ system in the body. In fact, one diagnostic registry service listed over 400 potential causes of vomiting in dogs! These notes summarize diagnostic approach and various treatment options for managing dogs and cats with vomiting. Vomiting refers to a forceful ejection of gastric and occasionally proximal small intestinal contents through the mouth. The vomiting act involves three stages: nausea, retching, and vomiting. Serious consequences of vomiting include volume and electrolyte depletion, acid-base imbalance, and aspiration pneumonia. It is essential that the clinician make a clear differentiation between regurgitation and vomiting at the outset. Regurgitation is defined as passive, retrograde movement of ingested material, usually before it has reached the stomach. Failure to recognize the difference between regurgitation and vomiting often leads to misdiagnosis. Regurgitation may occur immediately after uptake of food or fluids or may be delayed for several hours or more. A Detailed, Accurate History is ESSENTIAL One of the most important early considerations is to determine if any toxins or foreign objects may have been ingested. Some compounds can cause life threatening sequelae. The earlier a toxicity is identified, the greater the chance for successful management. Currently, xylitol toxicity is being recognized more frequently, and sago palm plants, which can cause severe hepatotoxicity in dogs and cats, are found in more homes and yards than in previous years. Cocoa mulch toxicity (theobromine) is also

occasionally seen. Many animals that have ingested toxins are presented with vomiting as a prominent sign. History and Clinical Assessment: Clinical Features Of Vomiting Because of the wide variety of disorders and stimuli that can cause it, vomiting may present the clinician with a major diagnostic challenge. A complete historical review with emphasis on all body systems is essential for determining a realistic and effective initial work-up plan and treatment protocol. All too often concentration on only the gastrointestinal tract leads to an incorrect diagnosis and inappropriate treatment. Consideration of the following features is useful in assessing and diagnosing a patient with vomiting: (1) duration of signs (2) signalment and past pertinent history (3) environment and diet (4) systems review (e.g., history of PU/PD, coughing and sneezing, dysuria or dyschezia, etc.) (5) time relation to eating (vomiting of undigested or partially digested food more than 8-10 hours after eating often indicates a gastric motility disorder [more common] or gastric outlet obstruction [less common]) (6) content of the vomitus (food, clear fluid, bile, blood, material with fecal odor), and (7) type and frequency of vomiting (projectile?, chronic intermittent?, cyclic?, morning vomiting only?). Most Common Causes of Acute or Chronic Vomiting in Dogs First need to Rule-Out: Dietary/ingestive problem (always investigate for any potential environmental materials that the patient may have been chewing on (plants [toxins], debris carpet, etc)  Indiscretion (e.g., table scraps, sudden diet change, garbage ingestion; toxins, foreign body, ingesting plants in home or yard)  Food adverse reaction (dietary sensitivity)  True food allergy Parasites  Intestinal (including Giardia)  Gastric (Physaloptera) Drug related problems  NSAIDS must always be considered  Other drugs (e.g., cardiac glycosides, antibiotics, chemotherapeutic agents)  Any drug can potentially cause vomiting, always ask about any supplements that are being given to a pet Metabolic disorders  Renal disease  Liver disease

 Electrolyte abnormalities  Addison’s disease (some are glucocorticoid and mineralocorticoid deficient and will demonstrate typical electrolyte abnormalities; others are only glucocorticoid deficient and require ACTH stim for diagnosis (JAVMA April 15, 2007, p. 1190-1194)

Rule-Outs for Chronic Vomiting, Once the Causes Listed Above are Ruled Out: Main Categories: Motility Disorders  Gastric hypomotility (an underappreciated disorder) Inflammatory Disorders  Chronic gastritis (with or without Helicobacter)  Inflammatory bowel disease Obstructive Disorders  Foreign body not already diagnosed (including cases with a partial small bowel obstruction that has eluded early diagnosis)  Hypertrophic gastropathy (uncommon) Neoplasia

Most Common Causes of Chronic Vomiting in Cats Dietary problem  Food adverse reaction (dietary sensitivity), up to 25% of cases IBD Hyperthyroidism Liver disease Renal disease GI lymphoma (intestinal is more common) Chronic pancreatitis Heartworm disease Intermittent Chronic Vomiting Chronic intermittent vomiting is a common presenting complaint in veterinary medicine. Often there is no specific time relation to eating, the content of the vomitus varies, and the occurrence of vomiting may be very cyclic in nature. Depending on the disorder, other signs such as diarrhea, lethargy, inappetence, and salivation (nausea) may occur as well. When presented with this pattern of clinical signs, the clinician should strongly consider chronic gastritis, inflammatory bowel disease, irritable bowel syndrome, and gastric motility disorders as leading differential diagnoses. A detailed work-up including gastric and intestinal biopsies is often required for definitive diagnosis in these cases. It is important to note that chronic intermittent vomiting is a common clinical sign of inflammatory bowel disease in both dogs and cats.

Vomiting from systemic or metabolic causes may be an acute or chronic sign and generally there is no direct correlation with eating and no predictable vomitus content.

Diagnostic Plan If reasonable concern is established based on the history (e.g., patient is inappetent, ingested a toxin, is vomiting frequently) or physical assessment (e.g., patient is listless, dehydrated, in pain), then a minimum data base of CBC, complete biochemical profile (or specific tests for evaluation of liver, kidney, pancreas, electrolytes), complete urinalysis (pre-treatment urine specific gravity extremely important for diagnosis of renal failure), and fecal examination is essential. The best way to screen for GI parasites on a single fecal sample is to run both a centrifugal flotation test and a Giardia antigen test. If only a single zinc sulfate centrifugal flotation is run, 25-30% of Giardia cases will be missed. T4 and both a heartworm antibody test and heartworm antigen test are considered routine baseline tests for vomiting cats (approximately 40% of cats with adult heartworms will have vomiting as a clinical manifestation of the disease). Survey abdominal radiographs are indicated if thorough abdominal palpation is not possible or suggests an abnormality (e.g., foreign body, pancreatitis, pyometra). Some institutions now routinely order 3 view abdomen films on patients presented for vomiting (both laterals and a VD). Unfortunately these tests are often not done early enough. Even if baseline results are unremarkable they are more than justified because they help to rule out serious problems at the outset (e.g., vomiting due to renal failure, diabetes mellitus, liver disease). Alternatively, any abnormalities provide direction for initial treatment and further diagnostics. The decision for performing more in-depth diagnostic tests is based on ongoing clinical signs, response to therapy, and initial test results. These tests include baseline cortisol or ACTH stimulation to confirm hypoadrenocorticism in a patient with an abnormal Na:K ratio or to investigate for this disorder if electrolytes are normal, complete barium series or BIPS study (for gastric or intestinal foreign body, gastric hypomotility, gastric outflow obstruction, partial or complete intestinal obstruction), cPLI* or fPLI*(canine and feline lipase immunoreactivity, respectively, for diagnosis of pancreatitis in dogs and cats), and serum bile acids assay (to assess for significant hepatic disease). Barium swallow with fluoroscopy is often necessary for diagnosis of hiatal hernia disorders and gastroesophageal reflux disease. Serum gastrin levels are run if a gastrinoma (Zollinger-Ellison Syndrome) is suspected. Pancreatitis: Pancreatitis continues to be a challenging disorder to accurately diagnose, short of thorough direct examination and biopsy. Assays for amylase and lipase are of very limited value, especially in cats. In general, the following can be stated regarding the various diagnostic tests for pancreatitis:

Value of the Various Diagnostic Tests for Pancreatitis Amylase/Lipase (sensitivity on lipase depends on which specific test is being done) - of value as a screening test in dogs only - need to be 3x or > above normal reference range in order to suggest pancreatitis - normal does not rule-out pancreatitis - **new lipase assay from Antech (2 DGGR) approximates sensitivity of PLI for diagnosis of pancreatitis - Antech has discontinued the somewhat less sensitive 1,2-diglyceride assay as of October 4, 2015. The new assay is 2 DGGR and is on every biochemical profile for dogs and cats (where lipase is normally included) Abdominal Ultrasound - highly specific, but not very sensitive, especially in cats Serum PLI - highly sensitive for pancreatitis Pancreatic Lipase Immunoreactivity (cPLI and fPLI) - Exocrine Pancreatic Insufficiency (EPI) o cPLI is reliably significantly decreased o cPLI is specific for EPI - Chronic Renal Failure o Increased, but usually still within reference range - Dogs with Biopsy Proven Pancreatitis o cPLI sensitivity is > 80% o currently recommended cutoff value for dogs is >200 ug/L o results are also promising for cats

Negative contrast gastrography. An excellent technique to quickly evaluate the stomach for presence of a nonradiopaque foreign body. Technique: Gastric tube, tranquilize as needed (definitely tranq cats) Dogs: 8-10 ml/lb air or stop if the animal shows discomfort Cats: 5 ml/lb air Remove tube, take rads immediately (left lateral, VD first) Can also use 60 ml carbonated beverage (e.g., Mountain Dew)

BIPS are barium impregnated polyethylene spheres. Traditionally, veterinarians have relied on barium liquid as the contrast agent of choice for gastrointestinal studies. However, recognized limitations of barium liquid have led to the development of barium-

impregnated solid radiopaque markers for the diagnosis of motility disorders and bowel obstructions. Barium liquid contrast studies are of limited value in detecting hypomotility. Radiopaque markers can be used to investigate a number of common gastroenteric problems. These spheres have been specifically validated for use in dogs and cats and are the only radiopaque markers with which there is extensive clinical experience in veterinary medicine. BIPS are manufactured in New Zealand and are now available in many countries. Information on availability of this product, including instructions on use and interpretation of radiographic studies, can be found at (www.medid.com; 800-262-2399). Ultrasonography can be useful in the diagnostic work-up of a number of disorders that can cause vomiting. Among the problems that may be detected with ultrasonography are certain disorders of the liver (e.g., inflammatory disease, abscessation, cirrhosis, neoplasia, vascular problems), gall bladder (cholecystitis, choleliths, gallbladder mucocele), GI foreign bodies, intestinal and gastric wall thickening, intestinal masses, intussusception, kidney disorders, and others. Needle aspirations and/or biopsies can be done at many sites under ultrasound guidance. One of the most reliable and cost efficient diagnostic tools currently available for evaluation of vomiting is flexible GI endoscopy. Endoscopy allows for direct gastric and duodenal examination, mucosal biopsy from these areas, and in many cases gastric foreign body retrieval. Endoscopy is considerably more reliable than barium series for diagnosis of gastric erosions, chronic gastritis, gastric neoplasia, and inflammatory bowel disease (a common cause of chronic intermittent vomiting in dogs and cats). It is stressed that biopsy samples should always be obtained from stomach and whenever possible small intestine regardless of gross mucosal appearance. Normal gastric biopsies may support gastric motility abnormalities, psychogenic vomiting, irritable bowel syndrome, or may be noncontributory (i.e., look elsewhere for diagnosis). Many dogs with vomiting due to inflammatory bowel disease have no abnormalities on gastric examination or biopsy. If only gastric biopsies are obtained, the diagnosis may be missed. Abdominal exploratory is indicated for a variety of problems including foreign body removal, intussusception, gastric mucosal hypertrophy syndromes, procurement of biopsies, and for resection of neoplasia. *fPLI is available at Texas A&M University. Serum samples can either be sent directly to the GI Laboratory at Texas A&M University, or they can be forwarded to Texas A&M by a commercial laboratory.

The address is: GI Lab at Texas A&M University College of Veterinary Medicine TAMU 4474 College Station, TX 77843-4474 979-862-2861 www.cvm.tamu.edu/gilab

Diagnosis of Vomiting • •

Stage 1—Baseline Assessment History and physical examination Conservative vs. more aggressive diagnostic plan based on patient’s condition and clinician’s concern

Conservative Approach Fecal examinationa Selected diagnostics Specific/symptomatic therapy

Serious or Systemic Clinical Signs Complete blood count Complete biochemical profile Urinalysis Fecal examinationa Parvovirus test if indicated Survey abdominal radiographs (3 views) T4 (cats) Heartworm antibody and antigen test (cats) Appropriate specific/supportive therapy

Stage 2—Further assessment (if vomiting persists or initial tests indicate further investigation should be performed promptly): •

Special Blood Tests —Corticotropin baseline or ACTH stimulation —cPLI or fPLI (pancreatitis) —Leptospirosis serology and/or lepto PCR —Bile acids assay (to asses liver function) —Coagulation tests (consider in patients with hematemesis/melena)

•

Contrast Radiography —Barium contrast —Air contrast gastrogram (to further assess for gastric foreign body) —BIPS (barium-impregnated polyethylene spheres; with food to assess GI motility)

•

Ultrasonography —Evidence of GI or non-GI disease —Aspirates or biopsy —Abdominocentesis

•

Nuclear Scintigraphy —Transcolonic portal angiography for detection of portosystemic anomaly —GI motility study

Stage 3—Invasive Procedures • •

•

Flexible GI endoscopyb (minimally invasive) —Examination, biopsy, foreign body retrieval Laparoscopy —Biopsies (e.g., liver, pancreas) —Aspirates (e.g., gall bladder, lymph nodes, mass lesion) —Intestinal biopsy Surgical intervention — Therapeutic or exploratory with multiple biopsies

aGI

parasites, including Giardia, should always be considered in dogs with acute or intermittent vomiting. Best baseline testing on a single fecal sample includes centrifugal flotation and Giardia antigen test. bEndoscopy

is a diagnostic or therapeutic tool that can be used in Stage 1, Stage 2, or Stage 3, depending on the clinical situation.

References Atkins CE: Feline heartworm disease. In Bonagura JB and Twedt DC, eds: Current veterinary therapy XIV, St. Louis, 2009, Elsevier, p. 831-836. DeNovo RC: Diseases of the stomach. In Tams TR, ed: Handbook of small animal gastroenterology, ed 2, Philadelphia, 2003, WB Saunders. Leib MS and Duncan RB: Gastric Helicobacter spp. and chronic vomiting in dogs. In Bonagura JB and Twedt DC, eds: Current veterinary therapy XIV, St. Louis, 2009, Elsevier, p. 492-496. Richards JR, Dillon R, Nelson T, Snyder, P: Heartworm-associated respiratory disease in cats â&#x20AC;&#x201C; a roundtable discussion. Veterinary Medicine June 2007. Tams TR: Gastrointestinal symptoms. In Tams TR, ed: Handbook of small animal gastroenterology, ed 2, Philadelphia, 2003, WB Saunders. Tams TR: Chronic diseases of the small intestine. In Tams TR, ed: Handbook of small animal gastroenterology, ed 2, Philadelphia, 2003, WB Saunders.

Acute and Chronic Diarrhea in Dogs and Cats Giardia, Clostridium perfringens Enterotoxicosis, Tritrichomonas foetus, and Cryptosporidiosis Todd R. Tams, DVM, DACVIM Chief Medical Officer VCA Los Angeles, California Introduction These seminar notes will focus on the diagnosis and management of important and sometimes challenging to diagnose causes of diarrhea in dogs and cats, with particular emphasis on Giardia, Clostridium perfringens enterotoxicosis, cryptosporidiosis, and Tritrichomonas foetus. These disorders should be investigated early in the course of diarrhea, whether it is persistent or intermittent, along with evaluation for dietary causes of GI signs (including both dietary indiscretion and adverse reactions to specific foods), nematode parasites, bacterial and viral causes, and acute idiopathic colitis. This group of disorders constitutes a thorough differential list for animals with acute and intermittent diarrhea (Table 1). The challenge to veterinarians is in making an accurate diagnosis, so that the most indicated therapy can be instituted as early as possible. This will then lead to the best opportunity for successful control of the medical disorder. It is also important to recognize that some animals may have several disorders at the same time (co-morbidities), so a thorough diagnostic approach is recommended. This is why it is often best to run tests for these disorders at the same time, through use of a â&#x20AC;&#x153;fecal diagnostics panelâ&#x20AC;? that is now available at many commercial laboratories. A single fecal sample is submitted to the lab, and tests for each of these disorders is done at the same time. This provides a prompt and thorough analysis for important clinical disorders of the GI tract. The clinician then has more clear direction on how to proceed with treatment, or other diagnostic tests in the event that none of these disorders is identified. It is also important to include blood tests for complete blood count, urinalysis, and complete biochemical profile to help evaluate for any major organ abnormalities (e.g., liver, kidneys, hypoproteinemia associated with protein losing enteropathy), especially in cases in which diarrhea does not resolve with the initial therapies and dietary changes. Only animals should have these tests done early in order to establish a minimum data base.

Table 1: Common Causes of Acute Diarrhea in Dogs and Cats

Young Animals

Older Animals

Dietary problems

Parasites

Parasites less common but always possible

- nematodes

- protozoa (Giardia, Trichomonads)

- coccidia (including Cryptosporidium)

Viral and bacterial

Viral causes uncommon in older animals

Clostridium perfringens enterotoxicosis

CPE (common in older animals)

(CPE)

Acute colitis (fairly common cause of diarrhea in older animals)

Giardia is an important cause of diarrhea, and for some patients other GI signs as well. It is an important pathogen in dogs and cats, as well as humans and other species. Historically, accurate diagnosis of Giardia has posed a significant challenge to veterinary practitioners, but there are now much more sensitive tests readily available for veterinarians to use on a routine basis. Because of the impact that this organism can have on animals, and also humans because of its zoonotic potential, it is important that veterinarians perform accurate diagnostic testing on animals to determine whether or not an animal is infected with Giardia. These notes will emphasize steps for accurate diagnosis, and also management of giardiasis. Clostridium perfringens enterotoxicosis is a common cause of intermittent diarrhea in dogs and cats. Veterinary practitioners should test for the enterotoxin whenever faced with a patient that has unexplained diarrhea. Cryptosporidiosis is now recognized to be a more common disorder in dogs and cats than was previously thought. It can cause significant abnormalities, and it has zoonotic potential. Cryptosporidiosis can be fatal in people that also are immunosuppressed (e.g., on chemotherapy or corticosteroids, carriers of HIV). Therefore, it is incumbent on veterinarians to test for this disorder, as there are important implications to both the patient as well as to humans who may come in contact with an infected animal.

Early Diagnostic Screening in Animals with Diarrhea Diarrhea – Making the Correct Diagnosis(es) Acute Diarrhea – DOGS (initial screening)

Acute Diarrhea – CATS (initial screening)

 Direct smear in house (fresh sample (perform by <1hr)  ZnSO4 w/centrifugation  Giardia antigen test  Parvo test if indicated

 Direct smear in house (fresh sample (perform by <1hr)  ZnSO4 w/centrifugation  Giardia antigen test

Later if Persistent:  Repeat all of the above  Cryptosporidium IFA  Clostridium perf enterotoxin assay

Later if Persistent:    

Repeat all of the above Cryptosporidium IFA Clostridium perf enterotoxin assay Large bowel signs?? > R/O Tritrichomonas foetus (special tests)

**Negative results do not rule-out any parasite. Be persistent, as retesting can be very important.

Diagnostic Approach to Acute Nonspecific Diarrhea 1. Differentials: First consider dietary problems, GI parasites, bacterial/viral infections, acute colitis. Test for parvovirus if clinical presentation warrants. *Make sure the client checks the home environment carefully to ensure there has not been ingestion of any toxins or other foreign material that could cause diarrhea, including plants and shrubs. 2. To rule-out parasites, test as indicated above in the box. If fecal tests are positive for parasites, treat accordingly. 3. If dietary sensitivity or indiscretion is considered a possibility, feed a controlled diet for GI problems, for 1-3 weeks. 4. Options on other therapies that can be tried include: metronidazole (bacterial diarrhea), probiotics (to help normalize the GI flora and competitively exclude pathogens), and motility modifier drugs (as long as there is not an infectious cause). If these therapies do not resolve the problem fairly quickly, other diagnostic testing should be undertaken.

Diagnosis and Management of Giardia Diagnosis Standard diagnostic tests used in any practice setting should include fresh saline fecal smears and zinc sulfate flotation with centrifugation. Zinc sulfate flotation with centrifugation, rather than gravity flotation alone, is a somewhat more sensitive means of 65

testing for Giardia and other parasites. Trophozoites are more likely to be found in loose stools, while cysts are more often found in semi-formed or formed stools. KEY POINT: Performing both zinc sulfate concentration with centrifugation and a Giardia antigen test together constitutes the most accurate means of evaluating a patient for the presence of Giardia. This has been recognized as the â&#x20AC;&#x153;gold standardâ&#x20AC;? in human medicine, and is true also in veterinary medicine. Direct Saline Smear Direct smears should be performed on fresh fecal samples as soon as possible after being passed, but definitely within 1 hour. A fresh saline smear is made by mixing a drop of feces with a drop of saline on a glass slide. A coverslip is applied and the preparation is examined immediately under 40x magnification. Trophozoites are pear-shaped and have a characteristic concave ventral disk. They demonstrate rolling/wobbling motion (e.g., like a falling leaf). Adding a drop of Lugolâ&#x20AC;&#x2122;s solution of iodine on the edge of the coverslip can be done as an optional procedure and this will enhance the morphologic features of the organisms and make them easier to find. The iodine kills the parasite, so motion will no longer be seen if this procedure is used. Differentiation of trichomonads from Giardia is based on a different motion pattern (more forward motion with trichomonads versus rolling motion with Giardia), the absence of a concave disk, a single nucleus, and the presence of an undulating membrane. Identification of Giardia trophozoites is diagnostic, while their absence in fecal samples does not rule out presence of infection. This is not a sensitive test, but it is quick and inexpensive and if trophozoites are seen, a diagnosis can be made quickly. Zinc Sulfate Concentration with Centrifugation Many studies have now shown that zinc sulfate concentration with centrifugation is the most reliable test available for demonstration of Giardia cysts in fecal samples. While zinc sulfate with centrifugation can be done in the hospital lab, our preference for many years has been to send fecal samples to a commercial lab for analysis. This is because the best accuracy in detection of Giardia is achieved through well trained and experienced lab personnel consistently setting up the assay and studying the microscopic specimens on time. For this reason many practices in the United States now submit fecal samples for centrifugation assays to a commercial laboratory. Zinc sulfate centrifugation is also a very effective method for identifying nematode eggs in feces. It is therefore now used as the standard test for screening for intestinal parasites in most academic and many private practices. Studies have shown that approximately 70-75 percent of Giardia positive dogs can be identified on a single zinc sulfate centrifugation test (as opposed to approximately 40 percent of dogs after 3 separate saline smear preparations). Slides should be examined within 10 minutes of preparation because the cysts may subsequently begin to shrink and will be more difficult to recognize. Since animals shed Giardia on an intermittent basis it is recommended that a series of 3 zinc sulfate concentration tests be run over a 3 to 5 day period, IF the Giardia antigen test is not run concurrently, in order to maximize chances of accurately diagnosing or ruling out Giardia in animals with chronic diarrhea. If there are 3 negative tests within 5 days, it is not likely the patient has Giardia. Diagnostic efficiency increases to 90-95 percent when 3 zinc sulfate examinations are conducted over a 3 to 5 day period. A positive result on any of the tests warrants treatment for Giardia.

Alternatively, however, an antigen test can be run at the same time as the centrifugation test to help increase diagnostic efficiency and accuracy. This is what I

recommend now as a standard practice, as the diagnostic sensitivity is higher (greater than 95%) and definitive results are obtained earlier. This is also more convenient (testing is done on one fecal sample on one day) and economical that doing 3 centrifugation assays over a 5 day period. Caution: It is not uncommon for plant spores, yeast bodies, and other amorphous debris to be mistaken for Giardia cysts. In fact, Giardia is frequently misdiagnosed â&#x20AC;&#x201C; either it is being diagnosed incorrectly, or the wrong tests are being run and animals with Giardia are being missed. Giardia cysts are 11-13 u in size, and the subtle characteristics of the nuclei, axostyles, and median bodies are often more easily observed under 100X oil immersion magnification. Sometimes there are crescent shaped indentations of the cyst wall. Yeast bodies are similar to Giardia in size, shape, and color. Yeast bodies appear to be far more common than Giardia. Zinc Sulfate Concentration - Summary - Zinc sulfate is the flotation solution of choice in small animal practices (excellent for detection of Giardia as well as nematodes) - Zinc sulfate concentration with centrifugation is the best test for identification of Giardia cysts (causes less distortion of Giardia cysts than standard salt solution) - The best overall test to perform on a single fecal sample is a combination of zinc sulfate centrifugal flotation and a Giardia antigen test.

Giardia Antigen Testing The fecal ELISA test detects Giardia antigen that is produced by dividing trophozoites. The test is very sensitive in humans and reportedly detects 30 percent more cases of Giardia than does zinc sulfate centrifugal flotation. Studies have now confirmed that this is also an excellent test for use in animals. One advantage of the ELISA test is that, since it detects Giardia specific antigen in the feces, it avoids the problem of intermittent cyst excretion in the feces. This test can be a significant aid in accurate diagnosis of Giardia in any private practice setting, and I highly recommend that veterinarians utilize this test in order to more consistently make an accurate diagnosis of giardiasis in their small animal patients. Indications for Running Giardia Antigen Test: - Cases of acute or chronic diarrhea in which zinc sulfate centrifugation tests are negative for parasites *Including young dogs with suspected viral or bacterial enteritis â&#x20AC;&#x201C; Giardia and other parasitic infections can significantly compromise animals with these conditions. I recommend that all puppies with parvoviral enteritis be screened early for parasites with a combination of zinc sulfate with centrifugation and a Giardia antigen test (both tests day one or two on a single fecal sample) - Cases in which it is unclear whether Giardia cysts are being seen on flotation tests (e.g., vs. plant spores) - For evaluation of animals with unexplained weight loss, unthriftiness, abdominal pain - Acute or chronic vomiting **(some animals with disease related to Giardia have only vomiting as a clinical sign) - Many hospitals are now using the ZnSO4 with centrifugation and Giardia antigen combination assay as a routine screening test for GI parasites and wellness testing, and these tests are often performed at a commercial laborary 67

rather than in the hospital setting (WHY? Significantly better quality control and more economical). This is because there are animals that have Giardia but that do not have any GI signs (loose stools, vomiting, etc) at the time of the exam. The addition of the antigen assay significantly improves the diagnostic sensitivity for Giardia. In summary, this approach offers: Better more sensitive diagnostic testing, more convenience to the client (one sample only), and ultimately it is more economical. Treatment of Giardia For many years the primary treatment for Giardia in dogs and cats involved metronidazole. For dogs in which metronidazole proved ineffective, other drugs such as fenbendazole or albendazole (Valbazen) were used. More recently it was shown that albendazole is highly effective in controlling Giardia. I recommended albendazole as an effective treatment for Giardia from 1993-1997, but experience with albendazole in dogs and cats has shown that it can cause bothersome side effects; including leukopenia, bone marrow suppression, lethargy, and inappetence. Therefore, I have not recommended albendazole for many years. I mention it here because some veterinarians still do use it. Fenbendazole (Panacur), well known for its effectiveness against a variety of intestinal parasites, is very effective against Giardia and is currently our primary therapy in most cases. In a controlled trial at Cornell University 6/6 dogs were effectively treated in an initial study. The same dose that is used to treat roundworms, hookworms, whipworms, and the tapeworm Taenia pisiformis (50 mg/kg orally once daily for 5 consecutive days [there have been treatment failures occasionally when therapy is given for only 3 days]) is used to treat Giardia. If the infection is not cleared on this regimen, a longer course of therapy is used (7 days). Fenbendazole has a proven track record for being very safe and is thought to not have any teratogenic effects. Fenbendazole is therefore the drug of choice for treatment of Giardia in pregnant animals. This is now also the preferred treatment for Giardia in cats. Drontal Plus (Bayer Animal Health) is also an excellent choice for treatment of Giardia. This product includes febantel in addition to praziquantel and pyrantel pamoate. Febantel is the drug component that treats Giardia. Febantel is metabolized into fenbendazole and oxyfenbendazole after oral administration. Drontal Plus is administered once daily for 3 to 5 consecutive days for treatment of Giardia. Drontal Plus has been approved for use in dogs. Drontal Plus has been administered to cats empirically at a dosage of two small dog tablets per cat (about 50 mg/kg febantel) orally for 5 days with subsequent demonstration of decreased shedding of cysts (Scorza, Radecki, and Lappin). Metronidazole is still a useful drug for treating Giardia, and it has the added advantage of having antibacterial as well as antiinflammatory properties. In situations in which it is unclear whether diarrhea is due to giardiasis, bacterial overgrowth, or mild inflammatory bowel disease, metronidazole is an good choice, especially when a client requests empirical therapy rather than definitive diagnostic testing. Metronidazole is only 67-74 percent effective in eliminating Giardia from dogs, however, and if a positive diagnosis is made fenbendazole or febantel would also be a reasonable choice. Potential side effects of metronidazole include anorexia, vomiting, and neurologic problems (ataxia, vestibular problems, seizures). In my experience these side effects are not common. They are more likely to occur when the anti-Giardia dose is used (25 mg/kg orally every 12 hours for 5 to 7 days). The total dose of metronidazole should never exceed 65 mg/kg per day (30 mg/lb per day). A lower dose (10 to 20 mg/kg every 12 hours) is used in treatment of intestinal 68

bacterial overgrowth and inflammatory bowel disease. Side effects are infrequent at this dose. In the past, if a 5 to 7 day course of metronidazole failed to eliminate Giardia, a longer follow-up course (10 to 14 days) was often used. With the availability of fenbendazole and Drontal Plus it is recommended that one of these drugs be used instead in this situation. Metronidazole neuro toxicity can be resolved more quickly by administering diazepam for several days. This is likely related to modulation of the GABA receptor within the cerebellar and vestibular systems. In addition to use of pharmacotherapy to eradicate Giardia, it is important to consider environmental control so as to minimize chances of reinfection, especially in kennel or cattery situations. Cysts present in a cool environment can remain infective for a long period of time. Cages and runs should be thoroughly cleaned of all solid fecal material. Steam cleaning, or treatment with a quaternary ammonium compound (e.g. A 33) are both very effective measures for killing cysts. Allowing time for thorough drying is important, to desiccate any remaining cysts. Bathing: Steps to prevent reinfection play an important role in resolution of giardiasis in dogs. Dogs may be reinfected with cysts from the hair or the environment, and bathing at the time that drug therapy is concluded, thereby removing cysts that could be licked from the hair coat by the animal, may be a very helpful additional step in decreasing the chances of reinfection. Changing the environment, if possible, can also be beneficial. Dietary Therapy and Supplementation: In animals that are known to be chronic carriers of Giardia, it may be benefical to supplement the diet with fiber. Increased dietary roughage may make it more difficult for Giardia trophozoites to attach to the small intestinal mucosa (use either commercial diets or simply add a fiber source such as Metamucil or pumpkin, for example, to the animal’s standard diet Rx for Chronic Giardiasis: Will Probiotics Help?  Lactobacillus johnsonii has been shown to inhibit Giardia proliferation in vitro  Due to alterations in pH from production of lactic acid  In guinea pigs, in vivo, prophylactic feeding of Lj greatly reduced fecal shedding following experimental inoculation with G. intestinalis  Enterococcus faecium SF68 fed to mice  Stimulated increase in anti-Giardia intestinal IgA and circulating IgG  Increased CD4+ immunocytes  Reduced shedding and more rapid clearance of Giardia?  Studies are ongoing Zoonotic Potential: Current information indicates that zoonotic potential exists with some Giardia genotypes, but certainly not all. When both animals and humans living in the same environment become infected, a common source of infection rather than direct transmission must also be considered. Are most Giardia spp. infections shared between animals and man? The genus Giardia contains multiple species of flagellated protozoans that are indistinguishable morphologically. Host specificity was thought to be minimal for Giardia spp., but not all small animal isolates cause disease in human beings. There have been varying results concerning cross-infection 69

potential of Giardia spp.. Human Giardia isolates usually grow in cell culture, animal isolates often do not. Recent genetic analysis has revealed 2 major genotypes in people. Assemblage A (G. duodenalis) has been found in infected humans and many other mammals including dogs and cats. Assemblage B (G. enterica) has been found in infected humans and dogs, but not cats. It appears that there are specific genotypes of Giardia that infect dogs (G. canis; Assemblages C and D) and cats (G. felis; Assemblage F) but not people. Accordingly, healthy pets are not considered significant human health risks for HIV infected people by the Centers for Disease Control (www.cdc.gov/hiv/pubs/brochure/oi_pets.htm).

Should Giardia Positive But Asymptomatic Animals Be Treated? The question whether animals that are asymptomatic carriers of Giardia should be treated is often asked. Giardia cysts have been found in many animals with well-formed feces. Giardia is clearly not pathogenic in some animals, while in others it causes significant enteritis. And there may be others that experience intermittent GI upsets that could potentially be related to chronic parasite carriage, and that may benefit in the long term from more effective parasite control. Because the public health considerations must still be considered, I do recommend that most animals with fecal samples that are positive for Giardia be treated, using these guidelines:  Administer Fenbendazole (Panacur) 5 days  Re-check fecal at 14-28 days, not later – use the zinc sulfate w/centrif assay, NOT the antigen test (we don’t know how long it takes to go negative)  If positive on O&P, treat once more  Fenbendazole again, or febantel (in Drontal PLUS); could also combine with metronidazole for this second round of therapy  If still not clinical, stop here, don’t re-check again  Pet is not clinical and likelihood of transmission of any infectious agent to a human is very low  Is the Giardia even a significant problem for the patient? NOTE: We do not want to overtreat! The antigen test should not be used as a recheck test in the immediate post treatment phase. The idea is to use the best diagnostic approach up front and then to manage the patient judiciously. Preventing Infection/Premises Control In controlled environments, the following methods should be used to keep the area as decontaminated as possible: 1. Decontaminate the environment 2. Treat all animals in the environment 3. Bathe at the conclusion of drug therapy to remove cysts from haircoats 4. Prevent reintroduction of infection In hospital and kennel/cattery situations (controlled environments) moving animals away from contaminated areas so they can be cleaned and decontaminated is very important. Steam cleaning after all fecal material has been removed is very effective. Chemical disinfection can be effectively accomplished using quaternary ammonium (QUAT) – containing disinfectants (e.g. Roccal, Totil), which will inactivate cysts in one minute at room temperature. The area should be allowed to dry completely and if possible left open for a 70

few days. Animals should be bathed with a general cleansing shampoo before being returned. In some situations, e.g., shelters, research facilities, it may also be advisable to bathe the animals a second time, especially around the perianal area, using a quaternary ammonium compound. These can be safely left on the coat for 3 to 5 minutes, before being thoroughly rinsed off (longer exposure can cause irritation). Allow the coat to dry thoroughly before returning the animal to the clean area, and then administer one more course of antiGiardia therapy, preferably using a different drug than was used during the initial course. Subsequently, any new animals introduced to the kennel or cattery should be tested as a matter of routine, but also bathed and treated as well, regardless of whether the fecal tests are positive or negative for Giardia.

Tritrichomonas foetus Tritrichomonas foetus is a recently identified enteric protozoan of cats. It causes chronic large bowel diarrhea (loose stools, presence of blood and mucus, straining to defecate), and is most commonly seen in young cats that have resided in densely populated housing such as catteries and shelters. The diarrhea may be intermittent or persistent. Loose stool may dribble out (lack of control) and the anal area may become edematous. The organism is present in the ileum, cecum, and colon as a trophozoite. The organism does not encyst, so trophozoites are the only recognized stage. Infection in feral cats and healthy cats appears to be uncommon. Until 2005 no effective treatment had been identified. Unfortunately, some cats with chronic diarrhea and dyschezia were euthanized due to a lack of any therapy that could control the clinical signs. It was exciting news in 2005 when Dr. Jody Gookin and colleagues at North Carolina State University reported that the nitroimidazole drug ronidazole is effective in controlling T. foetus. Although the diarrhea eventually resolves over a period of time (months up to one to two years) in untreated cats, ronidazole is the recommended therapy once a diagnosis has been established. It is important that an accurate diagnosis be made so that clients can be counseled appropriately, i.e., they should expect that their cat(s) will continue to have abnormal stools for some period of time. Further, there can be side effects of significant concern related to ronidazole, so this is NOT a drug that should be used empirically in lieu of testing. Also, it is not uncommon for cats to be co-infected with Giardia or Cryptosporidium or even both, so a thorough evaluation for parasites is important (run a minimum of one zinc sulfate with centrifugation and a Giardia antigen test and consider IFA fecal assays to check for Cryptosporidium). Accurate and thorough testing is essential and once any causative agents are identified they can be treated appropriately for the benefit of the patient and its owner. Tritrichomonas foetus is commonly mistaken for Giardia trophozoites on direct smear exam. All trichomonads possess three to five anterior flagella, an undulating membrane, and a recurrent flagellum attached to the edge of the undulating membrane. All flagella originate from an anterior basal body. An axostyle extends the length of the trichomonad and extends posteriorly. A cyst stage is not known for this genus. Video clips showing both Giardia and 71

Tritrichomonas trophozoites are available on the North Carolina State University website cited in the reference list below. Definitive diagnosis can be made in some cases by direct smear of fresh feces in saline and examined at 200 to 400x magnification. Sensitivity is low, however, for diagnosis by direct smear (only 14% in one study), so results can often be false negative. To increase the chance of finding Tritrichomonas trophozoites on direct smear, it is recommended that multiple direct smears be done on the same day. Whenever possible, a cat with suggestive signs should be hospitalized for part or all of a day so that each fecal sample that is passed can be examined quickly via direct saline smear. Tritrichomonas foetus can also be grown from feces via incubation at 37 degrees C in Diamondâ&#x20AC;&#x2122;s medium. A commercially available culture system is also available and is recommended for use in clinical practice (InPouch TF, Biomed Diagnostics Inc., San Jose, CA). The medium in InPouch does not support the growth of Giardia species or Pentatrichomonas hominis so presence of organisms is consistent with T. foetus. PCR is the most sensitive means for confirming a diagnosis. In one study of 36 cats with T. foetus infection, 20/36 were positive on the InPouch TF test and 34/36 were positive on PCR. Details on the PCR assay can be reviewed on the North Carolina State website. Studies at North Carolina State University in 2005 showed that ronidazole is effective for treatment of T. foetus. The original dosage guidance was to administer 30 mg/kg BID for 14 days. However, a study reported in 2008 provided new guidance: 30 kg/kg once daily is effective and safer, i.e., less likely to cause neurologic adverse events (RONIDAZOLE PHARMACOKINETICS IN CATS AFTER IV ADMINISTRATION AND ORAL ADMINISTRATION OF AN IMMEDIATE RELEASE CAPSULE AND A COLON-TARGETED DELAYED RELEASE TABLET; Levine, Papich, Gookin et al). Ronidazole is a nitroimidazole antimicrobial that is not licensed for any use in the U.S. The medication has become more readily available in the United States through compounding pharmacies. The drug has mutagenic properties, so it must be compounded the same way as chemotherapy drugs. We have had some cats experience mild neurological side effects to ronidazole, similar to what can be seen with metronidazole. These resolved upon discontinuation of the drug. It is expected that there will be fewer instances of neurotoxicity with the new schedule of 30 mg/kg on a once daily dosing schedule. It is important that an accurate diagnosis be made so that clients can be counseled appropriately, i.e., they should expect that their cat(s) will continue to have abnormal stools for some period of time until definitive treatment can be administered. Other recommended steps during therapy include isolating cats to decrease the risk of reinfection and to discard any litter boxes the cat has used, after treatment is completed. Follow-up testing: Dr. Gookin recommends testing by PCR at 1 to 2 weeks and 20+ weeks after treatment is completed. Negative results should be interpreted with caution since PCR cannot prove the absence of infection and prolonged symptomatic carriage of the organism after antimicrobial therapy may e common. An alternative drug which can be tried is tinidazole. This is also a nitroimidazole antimicrobial. A dose of 15-30 mg/kg SID can be tried. It should be safe and may or may 72

not be effective. Studies have been ongoing, however, and results have not been very impressive. References: Gookin JL: Tritrichomonas. In Bonagura JB and Twedt DC, eds: Current veterinary therapy XIV, St. Louis, 2009, Elsevier, p. 509-511. Gookin JL, Foster DM, Poore MF, et al: Use of a commercially available culture system for diagnosis of Tritrichomonas foetus infection in cats. J AM Vet Med Assoc, 222 (10), 2003.

**Website for periodic updates and video clips of motile trophozoites: www.JodyGookin.com. There is an excellent reference section titled AN OWNERS GUIDE TO DIAGNOSIS AND TREATMENT OF CATS INFECTED WITH TRITRICHOMONAS FOETUS.

Clostridium Perfringens Enterotoxicosis Over the last 20 years Clostridium perfringens enterotoxicosis (CPE) has been a frequently recognized cause of chronic intermittent diarrhea in dogs. Although it is likely a less common cause of diarrhea in cats it is still diagnosed frequently enough that it should be considered in the diagnosis of diarrhea in cats as well. This is not a new disease. Frequent use of the definitive test (enterotoxin assay performed on feces) for this disorder has revealed that CPE is seen relatively commonly in clinical practice and that CPE is a disorder that should be considered in any dog or cat with intermittent or chronic persistent diarrhea. C. perfringens is a normal vegetative enteric organism. Simply identifying C. perfringens on a fecal culture is meaningless. The pathogenesis of CPE is through an enterotoxin that is produced after certain strains of C. perfringens sporulate. The toxin damages epithelial cells of the distal ileum and colon. Inciting factors that promote sporulation are not clearly understood but may include stress, diet changes, concurrent disease, or inherent immune status. The most common clinical signs are chronic intermittent or persistent diarrhea. In some animals acute diarrhea is the primary sign. In fact, some of the cases of hemorrhagic gastroenteritis (HGE syndrome), characterized by acute bloody diarrhea and an increased packed cell volume that most practitioners have seen over the years, may have been due to CPE. Many animals exhibit signs of large bowel diarrhea, but small bowel signs may be seen as well. In some cases signs may be seen for only a day or two at a time, with persistent recurrences on a weekly, monthly, or on a less frequent basis. Stressful events or diet changes may incite flare-ups of clinical signs. In other cases C. perfringens enterotoxicosis is one of several problems that an animal may have concurrently and diarrhea may be persistent. Diagnosis CPE must be considered whenever more than one animal in the environment has diarrhea (e.g., household, kennel, cattery). Transmission from animal to animal can occur. A presumptive diagnosis may be suggested on fecal cytology in which more than 3-4 spores 73

per high power oil immersion field are observed (the spores have a safety pin appearance and are larger than most bacteria). However, definitive diagnosis is by identification of enterotoxin which is currently done via a fecal assay. Clinicians should be aware that simply seeing spores on fecal cytology does not establish a definitive diagnosis. Stool is submitted to the lab for enterotoxin analysis. Fecal samples that will be shipped off from the hospital directly to a laboratory should be sent on ice via overnight express. If a courier service will be picking up samples for transport to the laboratory it is sufficient to keep the sample refrigerated until pick-up. The courier service will keep the sample properly chilled during transport. The minimum amount of stool that should be submitted is the size of a pea. Typically I submit samples in a red top tube, without serum separator. In animals with intermittent diarrhea the chances of a positive toxin finding are greater when abnormal rather than a normal stool is examined. A negative result does not definitively rule-out CPE. DNA testing is now also available from several commercial laboratories as part of a fecal panel. Treatment Several antibacterial drugs are effective in controlling CPE. Acute cases often respond well to amoxicillin (22 mg/kg BID) or metronidazole (10-20 mg/kg BID) for 7-28 days. Many clinicians have likely treated CPE with these medications empirically without knowing what they were treating. Chronic cases tend to respond best to tylosin powder. The recommended dose is: Animals greater than 23 kg Âź tsp BID, 12 to 23 kg 1/8 tsp BID, 5 to 12 kg 1/12 tsp BID, and less than 4.5 kg 1/16 tsp BID (a â&#x20AC;&#x153;pinchâ&#x20AC;?). Cats definitely do not accept the powder well at all, even when it is mixed in very tasty foods. It is best to have the powder reconstituted to capsule form for administration to cats. The medication is very safe. Some animals require treatment for several to many months (3 to12 months or more). Over time the dose may in some cases be successfully reduced to SID and then every other day dosage (after several months or more on a BID schedule). Dietary fiber supplementation may also help control CPE. Probable mechanisms include decreased C. perfringens fecal concentration, lower colonic pH, which prevents sporulation, and increased concentrations of SCFA. Some patients may respond well to dietary fiber supplementation alone. Follow-up testing at 3-6 months can be done to determine if toxin persists. Once daily to every other day tylosin in conjunction with dietary fiber supplementation are used in chronic cases.

Cryptosporidiosis Infection with Cryptosporidium is more common than most small animal practitioners recognize. Currently it is recommended that all dogs and cats with diarrhea, whether acute or chronic, be screened for Cryptosporidium in addition to testing for nematode and protozoan parasites. In 2004 the American Association of Feline Practitioners adopted a position statement recommending that all kittens and adult cats with diarrhea be screened for Cryptosporidium. It is recommended that the same policy be followed with dogs (if the cause is not simple diarrhea related to an acute upset due to sudden change in diet or dietary sensitivity). Cryptosporidium spp. are coccidians that reside in the gastrointestinal tract. Infection can be associated with diarrhea in both immunocompetent and immunodeficient hosts. In the past, 74

most of the cases of mammalian cryptosporidiosis were attributed to C. parvum. However, molecular studies have demonstrated that cats are usually infected with the host-specific C. felis, dogs are infected with C. canis, and people are infected with C. parvum or C. hominus (Scorza and Lappin). In a recent study at Colorado State University, they documented the presence of Cryptosporidium spp. DNA in diarrhea from 24.3% of the 292 animals tested (180 cats, 112 dogs) (Scorza and Lappin). This highlights the importance of testing dogs and cats for cryptosporidiosis. PCR is much more sensitive than the tests that are used most commonly at this time (acid fast staining of fecal smears or IFA). In this same series with 24.3% positive on PCR, only 2.7% were positive on IFA. All dogs and cats infected with Giardia or Cryptosporidium species should be considered potentially zoonotic, even though the number of cases in which humans are infected through contact with pets is probably not high. Infection in humans is sometimes fatal in the presence of severe immunosuppression. Acute symptoms may include diarrhea, abdominal pain, vomiting, fever, and listless behavior. Infection can also be subclinical in dogs and cats. Chronic unresponsive diarrhea has been associated with cryptosporidiosis in cats with serious underlying disease as well as in dogs. Because Cryptosporidia oocysts are quite small (as little as one-tenth the size of common Isospora oocysts) and are usually present in the feces in small numbers, they are very difficult to detect on routine fecal flotation and microscopy. The best tests currently available for routine testing for Cryptosporidium are fecal IFA and acid fast staining of fecal smears; however, they lack sensitivity. These tests are readily available at commercial laboratories (acid fast staining can also be done in house). PCR is a much more sensitive test but is labor intensive, expensive and is only available at a limited number of laboratories. Antigen tests for detecting C. parvum in human species are not sensitive for use in dogs and cats. In time there will be more sensitive tests readily available. Treatment The following treatment regimens may be used for cryptosporidiosis: Canine

Feline

Azithromycin 5-10 mg/kg, BID orally,

Azithromycin 7-15 mg/kg, BID,

for 14-28 days

orally, for 14-28 days

Paromomycin 150 mg/kg, SID orally,

Paromomycin 150 mg/kg, SID orally, for 5 days

for 5 days

Tylosin 15 mg/kg, BID orally, for

21-28 days

Diagnostic Approach for Cats with Chronic Diarrhea PRE-BIOPSY work-up CBC, biochemical profile, UA, FeLV/FIV T4 (investigate for hyperthyroidism)  Fecal analysis  Direct smear for Giardia trophozoites and trichomonads  Giardia (ZnSO4 w/centrifug. and Ag test)  Clostridium perfringens enterotoxin assay  Cryptosporidium IFA  Rectal or fecal cytology (examine for inflammatory cells) Cobalamin assay (vitamin B12 fTLI (blood test for exocrine pancreatic insufficiency) Biopsies of the intestines are done to evaluate for inflammatory bowel disease and intestinal lymphoma. Biopsies can be obtained via either endoscopy or exploratory laparotomy

References Barr SC. Giradiasis. In Greene CE 3rd ed., Infectious Diseases of the Dog and Cat Philadelphia: Elsevier, 2006; 736-742. Blagburn BL and Butler JM. Optimize intestinal parasite detection with centrifugal fecal flotation. Veterinary Medicine 2006; 101: 455-464. Brown RR, Elston TH, Evans L, et al. American Association of Feline Practitioners 2003 Report on Feline Zoonoses. Comp Cont Ed Pract Vet 2003;25:936-965. Dryden MW, Payne PA, Ridley RK, Smith VE. Gastrointestinal parasites: The practice guide to accurate diagnosis and treatment. Suppl Compend Contin Educ Vet, July 2006; Vol. 28, No. 7(A) Gookin JL: Tritrichomonas. In Bonagura JB and Twedt DC, eds: Current veterinary therapy XIV, St. Louis, 2009, Elsevier, p. 509-511. Gookin JL, Foster DM, Poore MF, et al: Use of a commercially available culture system for diagnosis of Tritrichomonas foetus infection in cats. J AM Vet Med Assoc, 222 (10), 2003.

Scorza AV and Lappin MR. An update on three important protozoan parasitic infections of cats: cryptosporidiosis, giardiasis, and tritrichomoniasis. Supplement to Veterinary Medicine, March 2006; 18-32. Scorza AV, Radecki SV, and Lappin MR. Efficacy of a combination of febantel, pyrantel, and praziquantel for the treatment of kittens experimentally infected with Giardia species. J Fel Med Surg 2006; 8:7-13. Scorza AV, Lappin MR. Detection of Cryptosporidium spp. in feces of cats and dogs in the United States by PCR assay and IFA. J Vet Int Med 2005;19:437. Stockdale HD, Spencer JA, Dykstra CC, Blagburn BL, et al. Feline trichomoniasis: an emerging disease? Compend Contin Educ Vet, June 2006; 463-471.

Diagnosis and Management of Gastric Hypomotility in Dogs Todd R. Tams, DVM, DACVIM Chief Medical Officer VCA Introduction Functional gastric motility disorders have been recognized with increased frequency in veterinary medicine, but are often still overlooked in clinical practice. Gastroparesis is characterized by symptoms of gastric retention with objective evidence of delayed gastric emptying in the absence of mechanical obstruction. The frequency in small animal patients is unknown, but comparatively, it is estimated that gastroparesis affects up to 4% of the human population. Gastroparesis is a well-recognized syndrome in humans, and signs can range widely from mild intermittent symptoms of nausea, vomiting, and mild GI discomfort with little impairment to daily function, to the other end of the spectrum, with relentless vomiting and other symptoms and the need for frequent hospitalizations. Veterinarians should maintain an index of suspicion for this syndrome in dogs with intermittent vomiting and other signs of upper GI disease. Too often this particular disorder is overlooked and therefore the correct therapy may not be instituted as a result of misdiagnosis. There are many potential causes. Therapies include management of any underlying cause that can be identified (e.g., chronic gastritis, IBD), dietary measures, and drugs that stimulate gastric motor activity. Normal gastric motility is the result of the well-coordinated interaction of smooth muscle with neural and hormonal stimuli. Disordered motility disrupts the normal gastric functions of storage and mixing of food and its subsequent propulsion into the duodenum. Clinical Presentation The clinical presentation may include a variety of symptoms, the most common of which is vomiting that may be intermittent or more persistent. Other signs can include nausea, decreased food intake/early satiety, abdominal discomfort, periodic bloating, and borborhygmus. Some dogs may tend to vomit undigested food during the night or early the following morning, many hours after ingesting it (rule-out gastric hypomotility vs. mechanical obstruction in this situation). Weight loss may result from decreased food intake and/or chronic vomiting of undigested food. Several types of motility disorders are recognized in dogs. These include delayed gastric emptying, retrograde transit (duodenogstric reflux), and accelerated gastric emptying that occurs occasionally after gastroduodenal surgery. One syndrome many small animal practitioners readily recognize is early morning vomiting in small dogs. Usually these patients only vomit once or twice per episode and the content is mostly bilious fluid. This syndrome is thought to be related to gastric hypomotility with

prolonged retention of bilious fluid that refluxes into the stomach during the night. Dogs may feel uncomfortable in the early morning hours, perhaps related to nausea, and they seem to feel better after they evacuate the bile through vomiting. Etiology Gastroparesis may be associated with a number of clinical states that include inflammatory disorders (e.g., chronic gastritis, IBD), infectious disorders of the GI tract (e.g., parvovirus enteritis), gastric ulcers, infiltrative lesions (e.g., neoplasia), and chronic gastric dilatation. Metabolic disturbances that may cause gastric stasis include hypokalemia, hypercalcemia, acidosis, anemia, hypoadrenocorticism, diabetes, hypothyroidism, uremia, and hepatic encephalopathy. Short-term continued vomiting that is observed in some cases after apparent recovery from viral enteritis may be due to abnormal gastric motility. Transient (3 to 14 days) gastric hypomotility may also occur after gastric or any type of abdominal surgery. It is fairly common in the postoperative period after GDV or spinal surgery. Motility disorders with no organic cause may be best classified as idiopathic. Diagnosis of Delayed Gastric Emptying The first step is to determine whether prolonged gastric retention is due to mechanical obstruction or a functional motility disorder. A thorough history, physical examination, baseline tests to rule-out metabolic causes of vomiting, and survey abdominal radiographs are done first. Laboratory tests should include a CBC and complete biochemical profile, urinalysis, T4, and a fecal exam (to help rule-out GI parasites as a cause of vomiting). Baseline tests will help identify dogs with electrolyte abnormalities, diabetes, renal disease, etc. Anemia may be seen in ulcerative GI disorders, including benign or neoplastic diseases. Hypokalemia can result from acute or chronic vomiting and it can be a cause of gastric hypomotility. Diagnosis of idiopathic functional motility disorders can be challenging, but basically this is a diagnosis by exclusion, much the same way idiopathic epilepsy is diagnosed. Various known causes are ruled out first and then the diagnosis of idiopathic gastric hypomotility can be established. Special imaging studies and endoscopy are key diagnostic modalities. This will aid in ruling in or out a number of disorders that can cause prolonged gastric retention. Diagnostic Imaging for Delayed Gastric Emptying (Diagnostic Imaging Section Contributed by Dr. David Biller, DACVR, Kansas State University) Delay in gastric emptying may be secondary to a mechanical or functional problem. Pyloric obstructions may be due to hypertrophic changes, foreign bodies, and neoplasia. A differential diagnosis for what radiographically appears as a moderately

fluid distended stomach and suspicion of pyloric obstruction is a motility or functional problem. This can be due to propulsion disorders (poor or absent peristalsis) such as gastric smooth muscle problems, abnormalities of the antropyloroduodenal coordination, electrolyte disturbances, metabolic disturbances, or secondarily to drugs affecting gastric motility (atropine, antispasmodics, or certain tranquilizers). Gastric emptying of solids is of greater clinical significance because abnormal gastric emptying rarely is detectable in the liquid phase. The primary advantage of radiographic methods for assessment of gastric emptying in small animals is the widespread availability of radiographic equipment and expertise. Scintigraphy is the gold standard method for assessment of gastric emptying but requires administration of a radioisotope. Ultrasonography is a potentially useful, but subjective, method for assessment of gastric emptying in dogs. Radiographs: Gastric function and emptying cannot be evaluated on survey abdominal images. The use of positive contrast material is necessary for evaluation of emptying and function (peristalsis) of the stomach. Peristalsis and emptying can be directly visualized with the use of fluoroscopy and positive contrast material (which most small animal practices do not have). An alternative is taking radiographs with use of positive contrast and sequentially timed images. Peristaltic contractions are most obvious within the pylorus of the stomach. Gastric emptying with liquid barium contrast should be seen within 15 minutes in the normal patient. Generally the stomach will empty of liquid barium within 1 to 4 hours. Gastric emptying times are affected by volume of contrast used, type of contrast, concurrent use of medications, and stress (noise, fear, physical restraint, gastric intubation). Therefore, a small volume of contrast or stress may result in slow or delayed gastric emptying which may lead to misdiagnosis of a functional or mechanical outflow problem. Therefore, appropriate dosage and quiet environment should be obtained prior to study and diagnosis of delayed gastric emptying. Studies using barium mixed with food (barium meal) have also been done to attempt to be more physiologic in evaluation of gastric emptying (dosage of barium meal 10 to 12 ml/kg, acepromazine is the appropriate tranquilizer for dogs). A general rule is that gastric emptying begins within 20 to 30 minutes after administration of barium meal. This is often the liquid portion of the barium meal. The solid portion of the barium meal should start to empty within an hour. The range of gastric emptying with barium meal is quite wide being 7 to 15 hours. An alternative to using liquid barium (for evaluation of obstruction) or barium meal (solids) is using BIPS (barium impregnated polyethylene spheres) mixed with food.

BIPS are indicated for the diagnosis of gastrointestinal obstructions and gastrointestinal motility disorders in dogs and cats. Specifically, BIPS are helpful in detecting physical obstructions (including partial obstructions), functional obstructions (ileus), delayed gastric emptying due to pyloric stenosis or gastric rhythm disturbances and intestinal motility disorders. BIPS are radiopaque, barium-impregnated polyethylene spheres. They are radiodense and show clearly on abdominal radiographs. BIPS are packaged with an information booklet in a Dual Cap pack (Medical ID Systems, Inc., Grand Rapids, MI). The two diagnostic options of BIPS are: The primary functions of the large BIPS (5.0 mm) is the detection of gastrointestinal (GI) tract obstructions. The small BIPS (1.5 mm) mimic the passage of food, and their transit through the GI tract provides an accurate estimate of the gastric emptying rate and intestinal transit time of food. The Small Cap Option consists of 4 small gelatin capsules which are primarily formatted for administration to cats and small dogs. The Large Cap Option enables the same number of BIPS as in the Small Cap Option to be formatted as a single capsule for administration to large dogs or broken open and mixed with fiber diet. Some controversy exists about the accuracy of BIPS for gastric emptying evaluation. A study was done to compare gastric emptying of small BIPS in normal dogs with scintigraphy. It demonstrated significant differences in gastric emptying times between BIPS and scintigraphy. Barium series: With outflow obstruction gastric emptying time may be delayed to 3 or as long as 6 hours. With contrast material the pyloric canal may appear narrowed. Contrast may be seen extending through this concentrically narrowed and elongated pylorus and identified as a “beak” (bird’s beak) or “string” sign. The pyloric “tit” is the peristaltic pouch, or out pouching of the pyloric antrum along the lesser curvature as a peristaltic wave pushes contrast medium against the outflow obstruction Normal ultrasound appearance of the stomach: The animal should be fasted prior to ultrasonography if possible to decrease the amount of gas and ingesta in the stomach. A high frequency transducer is important (7.5-14 Mhz) to maximize resolution. As with all ultrasound studies a complete exam of the entire abdomen should be performed. This will insure that concurrent disease is not missed. For example GI disease is often associated with mesenteric lymphadenopathy or secondary to pancreatic disease. Complete ultrasonographic examination of the stomach includes evaluation of wall thickness and layering, evaluation of luminal contents and quantifying gastric motility/peristaltic function. Some feel that ultrasound may eliminate the need for barium gastric emptying and motility studies in patients with gastric motility disorders. The stomach should be scanned in both the longitudinal and transverse planes. As with radiographs the appearance will vary depending on the degree of distention and the luminal contents. In the normal dog the gastric wall is 3-6 mm thick when the stomach is moderately distended and may be slightly thicker when the stomach is not distended. These thickness measurements of the stomach are taken between rugal folds. Gastric rugae can be recognized in the fundus and body of the stomach, and their thickness

depends on the degree of gastric distension. The use of real time ultrasonography to evaluate gastric motility should be included in the examination. The mean number of peristaltic contractions in the stomach is 4-5 per minute. If the stomach is distended with fluid the outflow area should be evaluated to see if fluid empties the stomach and enters the duodenum. The presence of gas in the stomach could complicate the assessment of gastric emptying by this method. The principle advantage of ultrasonography is that it allows gastric emptying and antral contraction to be assessed in real time and with minimal restraint of the animal. In dogs, gastric contractions can be visualized with ultrasonography, and delayed gastric emptying might be indicated by prolonged retention of fluid. Endoscopy in Investigation of Functional GI Disorders Endoscopy is useful for direct examination of the esophagus (evaluate for evidence of esophagitis which can result from gastroesophageal reflux), gastroesophageal junction area, the entire luminal stomach, pylorus, and upper small intestine and also for procurement of mucosal biopsy samples for diagnosis of chronic gastritis, IBD, and neoplasia. Endoscopy is also excellent for identification of gastric problems including mechanical obstruction (e.g., visualization of foreign bodies, antral polyps, hypertrophic gastric antral or pyloric disease [hypertrophic gastropathy], ulceration, and luminal neoplasia). Findings that should alert the endoscopist to the possibility of a motility disorder include retention of food or fluid admixed with bile in a properly fasted patient and generalized erythema with or without the presence of streaks of bile-stained fluid. Another important finding is any evidence of esophagitis with or without laxity at the lower esophageal sphincter area (consider gastroesophageal reflux disease in conjunction with gastric hypomotility). These endoscopic findings all provide valuable diagnostic â&#x20AC;&#x153;clues.â&#x20AC;? Negative endoscopic biopsy results in conjunction with normal baseline laboratory tests are very helpful in reaching a conclusion that a functional gastric disorder is idiopathic. Treatment of Functional Gastric Motility Disorders For any patient with a primary cause that has been identified (e.g., hypokalemia, uremia, hypothyroidism, IBD, etc.) treatment is first directed at that disorder. In these patients ancillary dietary therapy and gastric prokinetic therapy may or may not be indicated but can certainly represent a valuable short-term adjunct to the primary therapy in these cases. Dietary management involves feeding divided meals 2 to 4 times a day (less volume per meal) and feeding a restricted fat food (the higher the fat content, the longer it takes

the stomach to empty). Some dogs with a milder degree of gastric hypomotility respond well to dietary measures alone. In these cases it may be beneficial to start by feeding a restricted fat canned food several times a day, since canned foods will naturally break down more readily in the stomach compared to dry foods. If clinical signs are well controlled on the canned diet (i.e., vomiting has stopped), then a gradual switch to a dry food can be made over time on a trial basis (try after a month or so) and many dogs are able to tolerate this very well. Pharmacotherapy for gastric hypomotility involves administration of drugs with a gastric prokinetic effect. Currently, the most commonly used drugs in small animal medicine are metoclopramide and cisapride. While cisapride is a superior prokinetic drug, metoclopramide is an effective drug for many patients and is often the first drug selected, with cisapride used as a second choice if metoclopramide is not effective. Other drugs that are sometimes used for prokinesis are low dose erythromycin and the H2-receptor blocker ranitidine (Zantac). Metoclopramide has been used as the primary treatment on a long-term basis for idiopathic hypomotility disorders. Metoclopramide has also been useful in treatment of dogs that have chronic vomiting characterized by episodes occurring routinely in the early morning and containing bilious fluid, often with once daily dosing at bedtime in this situation. In general, patients less than 4.5 kg (10 pounds) receive 2.5 mg per dose at the start of therapy, 5 -18 kg (11-40 pounds) 5 mg per dose, and greater than 18 kg (40 pounds) 10 mg per dose. Unless vomiting is occurring only intermittently, metoclpramide is generally started at three doses per day and then tapered over time based on response. Prokinetic drugs should be given 30 to 45 minutes before meals and again at bedtime. Animals that require chronic medication may ultimately need only one to two doses daily. Some dogs require three doses per day on a longterm basis, and in others it may be possible to discontinue therapy entirely at some point. Metoclopramide is less effective as a promotility drug than cisapride (see later discussion). Metoclopramide is effective at facilitating emptying of liquids but is less effective than cisapride in promoting coordinated gastroduodenal activity and emptying of solids. Some adverse effects may occur if metoclopramide is given in the usual therapeutic doses. Clients should be apprised of these before the medication is prescribed. These effects are uncommon in animals, and somewhat more common in humans. Motor restlessness and hyperactivity may occur; and when observed, these signs usually begin 20 to 30 minutes after a dose and last four to five hours. The reaction can range from mild to quite dramatic. Alternatively, drowsiness and depression occasionally occur. Hospitalized animals may chew excessively at catheter sites or be more aggressive toward hospital staff. Sometimes these effects are subtle and house staff need to be observant. These side effects are reversible

(diphenhydramine [Benadryl 2.2 mg/kg [1 mg/lb] IV) or by discontinuing the drug) but generally do not subside when lower doses are given. Cisapride does NOT cause these same type of adverse reactions. Metoclopramide crosses the blood brain barrier, cisapride does not. In general, metoclopramide should not be given to epileptic patients. Other contraindications include evidence of significant mechanical obstruction, simultaneous use of anticholinergic agents (antagonism of metoclopramideâ&#x20AC;&#x2122;s effects), and pheochromocytoma. Cisapride is a potent GI prokinetic drug. It is no longer on the market for use in humans, as of 2000, because of an association with fatal arrhythmias. There are no reports of similar complications existing in dogs and cats, however. Cisapride has broader GI prokinetic effects than metoclopramide (e.g., cisapride has demonstrated excellent efficacy in management of colonic inertia and small intestinal ileus). Cisapride is unique among prokinetic agents in that it does not have antidopaminergic properties. Whereas metoclopramide antagonizes the inhibitory effects of dopamine and can cross the blood-brain barrier, cisapride has no effect on the central nervous system. In contrast to metoclopramide, which has central effect at the CRTZ in addition to its peripheral effects, cisapride has no known direct antiemetic properties. Another contrast is that metoclopramideâ&#x20AC;&#x2122;s prokinetic effect is most significantly on the stomach. It is NOT a reasonable choice for treatment of small intestinal ileus. The onset of pharmacologic action of cisapride is approximately 30 to 60 minutes after oral administration. Cisapride increases lower esophageal pressure and lower esophageal peristalsis compared to placebo and/or metoclopramide. It significantly accelerates gastric emptying of liquids and solids. Small intestinal and colonic motor activity are also significantly enhanced. It enhances antropyloroduodenal coordination, and increases propagation distance of duodenal contractions. The most relevant uses of cisapride in animal patients include treatment of gastroparesis, especially in patients that experience significant side effects from metoclopramide (e.g., hyperactivity and other dystonic reactions) or where metoclopramide is not sufficiently effective, idiopathic constipation, gastroesophageal reflux disease (if H2-receptor antagonists or proton pump inhibitors and dietary management alone are not effective), and postoperative ileus. The suggested dose of cisapride is similar to what has been recommended for metoclopramide (0.2-0.5 mg/kg [0.1 - 0.25 mg/lb] orally one to three times daily depending on the clinical situation). In general, patients less than 4.5 kg (10 pounds) receive 2.5 mg per dose at the start of therapy, 5 -18 kg (11-40 pounds) 5 mg per dose, and greater than 18 kg (40 pounds) 10 mg per dose. The dose can be gradually increased if necessary. As is recommended for metoclopramide, cisapride should be administered no closer than 30 minutes before feeding.

Erythromycin evokes gastric prokinetic effects by action on neural and smooth muscle receptors for the hormone motilin, the physiologic regulator of fasting gastroduodenal motor complexes. Erythromycin can significantly stimulate emptying of both liquids and solids from the stomach, inducing strong antral contractions. However, this effect may work in a counteractive way to small intestinal feedback control mechanisms and early evacuation of larger than normal food particles with dumping into the intestine may occur. The prokinetic dose is somewhat lower than what is used for antimicrobial therapy. The dose range for gastrokinesis is 0.5 to 1 mg/kg (0.25 to 0.5 mg/lb) orally TID, administered between meals. Erythromycin and cisapride are considered the two most effective prokinetic drugs in dogs. Ranitidine (Zantac) and Nizatidine (Axid) are H2-receptor antagonists that are used primarily to inhibit gastric acid secretion (nizatidine is used mostly in humans). These drugs also stimulate GI motility by inhibiting acetylcholinesterase activity, thereby increasing the amount of acetylcholine available to bind to smooth muscle muscarinic receptors. The effect is mostly gastric prokinesis, and there is also a mild increase in small intestinal and colonic motility. These drugs are generally not used as primary prokinetic agents, as other drugs are somewhat more effective. The dose is 0.5 to 1 mg/kg (0.25 to 0.5 mg/lb) orally three times daily. They may provide benefit when both prokinesis and gastric acid reduction are needed. However, other drugs are more effective for gastric acid control (e.g., famotidine, omeprazole, lansoprazole). Decisions on therapy are made based on the overall condition of the patient and whether a condition is considered to be mild or more severe. Treatment decisions on which drugs to use are based on a knowledge of expected effects from each drug and an understanding of each patientâ&#x20AC;&#x2122;s disorder. Response to therapy is monitored and adjustments are made if there is a less than desirable effect. Treatment periods of 5 to 14 days are reasonable for assessment of effectiveness or lack thereof for whichever therapeutic programs are selected. As stated above, duration of therapy is entirely patient and condition dependent. Some dogs with idiopathic hypomotility may require lifelong therapy, while others may get off treatment after several months. Some will ultimately do well with only one dose of prokinetic medication per day. Dogs with bilious vomiting syndrome, which is characterized by intermittent early morning vomiting of bile, may respond to feeding at bedtime (food adsorbs bile refluxed into the stomach during the night) and/or a single dose of prokinetic therapy administered at bedtime.

INFLAMMATORY BOWEL DISEASE AND INTESTINAL LYMPHOMA IN CATS Todd R. Tams, DVM, DACVIM VCA Antech Los Angeles, California David S. Biller, DVM, DACVR Kansas State University Manhattan, Kansas Howard B. Seim III, DVM, DACVS Colorado State University Ft. Collins, Colorado

Inflammatory Bowel Disease Inflammatory bowel disease (IBD) is not a specific diagnosis, rather it is a histological description of a syndrome resulting from a host hypersensitivity response to antigenic stimuli. In IBD there is an increase in the inflammatory cell population in the intestinal mucosa. The predominant inflammatory component in cats with IBD can be lymphocytic-plasmacytic (most common type), eosinophilic, or neutrophilic. Changes in mucosal architecture and cell morphology should also be noted (crypt lesions including abscesses, villus atrophy or fusion, edema, epithelial erosions or ulceration, fibrosis). The etiology of IBD is poorly understood. Primary causes of initiation and perpetuation of intestinal inflammation that should be considered include parasites, bacteria (specific agents including normal luminal bacteria or bacterial overgrowth), immune-mediated diseases, and food sensitivities. Many cases of IBD are likely idiopathic in nature. Clinical Course Inflammatory bowel disease (IBD) currently is recognized as a common and important medical problem in cats. Three general types of clinical presentations have been identified in cats with idiopathic IBD: (1) a clinical course characterized primarily by vomiting, (2) a clinical course characterized primarily by diarrhea, and (3) a clinical course that includes both vomiting and diarrhea as primary signs. Associated clinical signs can include change in appetite (anorexia, inappetence, or ravenousness), weight loss, and lethargy. In some cats, the clinical signs are cyclic; they seem to flare up and then abate in a predictable pattern. Vomiting, one of the most frequent clinical signs of IBD in cats, is most often recognized as an intermittent occurrence for weeks, months, or years. As the disorder progresses, an increased frequency of vomiting often leads the owner to seek veterinary attention. In addition to vomiting, diarrhea is a common sign observed in feline IBD and most likely is due to derangement of normal mechanisms of absorption and motility caused by mucosal inflammation. In most cases, diarrhea is intermittent early in the course of the disorder, and there may be a transient response (weeks to several months) to

dietary manipulation or any of a variety of medications (in some cases, however, dietary manipulation can effect excellent control and drug therapy may ultimately not be necessary). Later, the diarrhea becomes persistent and usually responds only to specific treatment, which is determined after a definitive diagnosis is made. Signs of small bowel diarrhea predominate, but signs of large bowel diarrhea may be evident as well if there is generalized intestinal tract involvement. Appetite changes in cats with idiopathic IBD vary from decreased appetite to complete anorexia to ravenousness. Inappetence seems to occur more commonly in cats that have vomiting as the primary clinical sign and usually occurs during exacerbation of clinical signs, and vomiting or diarrhea is not observed until later or not at all. The three leading differential diagnoses for a cat with a ravenous appetite, diarrhea, and weight loss are IBD, hyperthyroidism, and exocrine pancreatic insufficiency (uncommon). Diagnosis A definitive diagnosis of IBD can be made based only on intestinal biopsy (performed either at endoscopy or exploratory laparotomy, and ensuring that both upper and lower [ileum] biopsies are obtained). A definitive diagnosis of IBD cannot be made based on barium series radiography or ultrasonography. Diagnostic work-up prior to performing biopsies includes baseline testing to evaluate the overall health status of the patient and to rule out other disorders. Recommended baseline tests include a complete blood count, complete biochemical profile, urinalysis, fecal exams for parasites, serum thyroxine test, serum cobalamin level, and FeLV/FIV. Cats with chronic vomiting should be screened for heartworm disease. fTLI is done to rule-out exocrine pancreatic insufficiency. Ultrasonography is useful for assessing the abdominal organs, intestinal wall thickness, searching for any masses, and examining for lymphadenopathy. Dietary sensitivity is a common problem in cats with vomiting and/or diarrhea and food trials are an important part of the diagnostic work-up, especially early in the clinical course. Hydrolyzed protein and novel protein foods should be fed for 2-3 weeks at a time to determine if dietary therapy will either reduce or resolve the problem entirely. Abdominal Imaging in Cats â&#x20AC;&#x201C; IBD vs. Lymphoma Radiology Radiography is important for diagnosing intestinal diseases. During evaluation of the small bowel on survey radiographs, important factors that should be evaluated include location of small intestine (normally fills the abdomen where nothing else is present, not unusual to be mostly right-sided in cats), appearance of bowel contents (gas, fluid, or mottled material), contour of small bowel, and diameter of the small intestine. The normal diameter in cats is up to 12 mm. In normal animals, intestinal luminal contents should appear as a homogeneous fluid opacity. Disease of the small intestine may be missed on survey films unless there is a change in bowel opacity (mineralized mass or foreign material), luminal diameter (functional ileus or complete or partial mechanical obstruction), or changes in contour of the small bowel (linear foreign body).

Contrast studies (upper GI series) are often necessary to identify normal or abnormal shape, diameter, or continuity of small bowel. The transit time of barium varies greatly in cats. It usually travels from the stomach through to the ileum in about 60 minutes, although it can take as long as 4 hours. The range of transit times for organic iodides through the small bowel is approximately 15â&#x20AC;&#x201C;90 minutes. The organic iodide usually reaches the ileum and colon in less than 60 minutes. Small Intestinal IBD Diagnostic radiographs are recommended in the work-up of cats with gastrointestinal signs. Although survey and contrast radiographs are usually not specific/diagnostic for IBD, abdominal radiography is most helpful in defining extra-alimentary tract disorders causing gastroenteritis. Survey radiography might detect organomegaly (liver, kidney) unrelated to IBD or intestinal obstruction that might cause similar GI signs. Survey radiographs of inflammatory bowel disease are usually normal. There is no consistent radiological finding in cats with inflammatory bowel disease. The intestines may appear thickened (intestinal thickness cannot adequately be determined on survey radiographs), or luminal fluid maybe increased and there may be more gas than normal in the intestines, but these signs can occur in many conditions. Contrast examinations (upper GI series) are helpful in identifying a mass or obstruction. With contrast, assessment of the location and extent of the intestinal lesion may be more accurate than on survey images. Changes associated with IBD on barium study are often not present. With severe inflammatory however; changes may include: irregular mucosal lining abnormalities and thickened intestinal walls. In most cases contrast radiography is unrewarding. Intestinal Lymphoma Survey radiography might detect organomegaly (liver, kidney, lymph nodes) associated with lymphoma. Radiographic findings may reveal a mid-abdominal mass associated with the GI tract and/or mesentery, or localized or diffuse decrease, or loss, of serosal detail suggestive of peritoneal effusion. If a mass is suspected radiographically or historically, or a mass has been palpated, then compression radiography may be helpful to isolate and visualize the mass. Obstruction occurs more often with adenocarcinoma of the small intestine than with small intestinal lymphoma. Contrast examinations (upper GI series) are helpful in identifying the mass or the obstruction. With contrast, the location, bowel wall thickening, mucosal irregularity and extent of the intestinal lesion may be more accurate than on survey images. Ultrasonography of the Feline Small Intestines The small intestines can be seen throughout the abdomen, both end-on and longitudinally oriented. The duodenum has a slightly larger diameter than the rest of the small intestinal loops, and is the most lateral and ventral bowel loop in the right cranial abdomen. It can be located usually just ventral and lateral to the right kidney and followed cranially into the pylorus. The ileum has a distinct cross-sectional appearance (resembling spokes on a wheel) and can be visualized as it enters the colon, just medial to the right kidney. The colon typically is gas-filled, with poor visualization of the lumen.

The following five layers are present in the intestinal wall, from outside to inside: Serosa: Thin hyperechoic layer Muscularis: Thin hypoechoic layer Submucosa: Thin hyperechoic layer Mucosa: Prominent hypoechoic layer (typically the thickest layer) Mucosal surface–lumen interface: Hyperechoic layer in the center of the bowel These individual layers are best visualized with higher-frequency transducers. Normal wall thicknesses have been established in the cat for various segments of the GI tract: Duodenum: 2.0–2.4 mm (mean of 2.2 mm) Jejunum: 2.1–2.5 mm (mean of 2.3 mm) Ileum: 2.5–3.2 mm (mean of 2.8 mm) Colon: 1.4–l.7 mm (mean of 1.5 mm) One to three contractions per minute should be seen with normal small intestinal peristaltic activity. Ultrasonographic features of intestinal disease include bowel wall thickening, loss of wall layers, loss of motility, and regional lymph node involvement. Intestinal Ultrasound: IBD versus Lymphoma An abdominal ultrasound examination may be helpful in cases of suspected small intestinal disease. Abdominal ultrasound is superior to radiology in defining focal versus diffuse disease, loss of layering, intestinal thickening and mesenteric lymphadenopathy seen with IBD and lymphoma. Ultrasonography also allows for precise guidance of fine needle aspiration or biopsy for cytologic or histopathologic sampling of small intestinal disease and associated lymphadenopathy. Ultrasonography can also be used to assess response to therapy noninvasively. A limitation of ultrasonography would be the difficulty in assessing the exact anatomic location (duodenum and ilium should be more easily identified by an experienced operator). Findings may be normal, especially in cases of low-grade small cell lymphoma or mild IBD Changes of the small intestine may or may not be present dependent upon chronicity and/or severity. The changes may be diffuse or focal. The intestine may appear normal. Biopsy is indicated to confirm disease. The most common finding with inflammation is normal to symmetric wall thickening with the layering retained. In comparison, neoplasia is usually localized with greater wall thickness and loss of normal layering. These categories can overlap, and therefore cytology or histopathology is required for definitive diagnosis. Acute enteritis or inflammatory bowel disease may demonstrate corrugation of the intestine on ultrasound

examination. Ultrasound of IBD With inflammatory bowel disease, the intestine may be normal on ultrasound. The measurement of the intestinal wall thickness by ultrasound is neither specific or sensitive for diagnosing IBD. Changes, especially those of severe or chronic disease, have been reported as focal to diffuse thickening, altered echogenicity, poor intestinal wall layer definition, and mild enlargement of adjacent lymph nodes. Mucosal echogenicity may remain hypoechoic. Round, enlarged, hypoechoic lymph nodes may be more consistent with neoplasia, while inflammatory lymph nodes may be enlarged but tend to maintain their normal shape. Ultrasonographic Measurements of Feline Abdominal Lymph Nodes US Length (mm) US Diameter (mm) Frequency of detection Jejunal

20.2 (11.4-39.0)

5.0 (2.8-7.2)

90%

Colic

9.0 (4.6-12.1)

3.1 (1.9-5.2)

50%

Ultrasound of Intestinal Lymphoma Perform abdominal ultrasonography to evaluate the extraintestinal organs in addition to GI tract wall thickness, layering, and motility. Lymphoma most commonly presents as transmural, circumferential, homogenous, hypoechoic thickening with loss of normal wall layering. Lymphoma tends to involve a long bowel segment or multiple bowel segments. Regional moderate, hypoechoic lymphadenopathy is generally present. Lymphoma is less likely to cause obstruction of the lumen. Six major patterns of ultrasonographic features in feline lymphoma include: transmuralcircumferential, symmetrical and asymmetrical, transmural-bulky, transmural-nodular, transmural-segmental, and mucosal infiltration. The transmural-circumferential pattern is most common. The transmural-bulky pattern has been described as a space occupying mass representing the thickened wall with areas of increased and decreased echogenicity. The transmural-segmental pattern has been described as wall thickening involving only a portion of the wall. The transmural-nodular pattern appeared as nodular wall infiltration and local nodular spread into the mesentery. Mucosal infiltration pattern demonstrated mild thickening of the intestinal wall associated with faint hyperechoic foci throughout thickened mucosal layer. In cats GI lymphoma can affect the intestinal tract without disrupting the wall layering. Ultrasonographic Evaluation of Muscularis Propria in Cats with Diffuse Small Intestinal Lymphoma or IBD It is difficult to detect small intestinal lymphoma or IBD in cats without a mass lesion, loss of layering or thickened bowel wall. Thickening of the muscularis propria is associated with diffuse infiltrative bowel disease such as lymphoma or IBD in cats. This 5

has also been seen in normal cats as well. The most common ultrasound descriptions of GI lymphoma in cats are as mass lesions previously discussed. Intestinal Biopsy Techniques Endoscopic Biopsy: Endoscopy is a minimally invasive procedure in which multiple biopsies can be obtained and this procedure generally has greater client compliance than with surgery because it is less invasive and less expensive than exploratory abdominal surgical procedures. Endoscopy is considered a gold standard procedure for tissue collection. Operator experience and the quality and number of biopsy samples obtained are very important. Endoscopy offers a means of examining the upper and lower small intestine, stomach, and colon. It is especially advantageous because biopsies can be obtained early in the course of the disorder, at a stage when a client will likely be reluctant to agree to an exploratory surgery for their pet. The degree of intestinal changes noted on biopsy also provides useful guidelines for both type and duration of therapy that will be needed to control the specific disorder. Clinicians need to make sure they are taking an adequate number of endoscopic biopsy samples for accurate diagnosis. Even expert endoscopists report that in some cases one-fourth to one-third of the biopsy samples they take from a patient will have some degree of damage to the tissue that may preclude the samples from being useful or representative. Therefore, it is recommended that clinicians take 8 to 12 biopsy samples from the upper small intestine so that the pathologist will have enough tissue to work with. Also, it is recommended that both upper and lower GI endoscopy be done on cats with chronic GI signs (vomiting and/or diarrhea, weight loss). In this way biopsies from the ileum can be obtained by passing the endoscope along the full length of the colon up to the level of the ileocolic orifice. It is very important that the effort be made to obtain ileum samples, since some cats with small cell lymphoma have disease in the ileum but not in the upper small intestine. The diagnosis can be missed in these cats if only upper small intestinal biopsies are obtained. When a pediatric diameter endoscope is used it is possible in most dogs over 4 to 5 kg to advance the endoscope through the ileocolic orifice and into the ileum, where it can then be advanced along the terminal ileum for exam and biopsies. However, in cats the ileocolic orifice is very small and in most cats it is not possible to advance the endoscope through this junction and into the ileum. In cats ileum biopsies are obtained blindly by advancing the endoscopic biopsy instrument through the ileocolic orifice with the endoscope tip positioned at the ileocolic sphincter area. Usually 3 â&#x20AC;&#x201C; 4 samples are procured in this way. Colon biopsies are always obtained as well during colonoscopy in order to evaluate for inflammation in the colon. Surgical Biopsy Techniques for Abdominal organs Biopsy. Organ biopsy is usually required to confirm feline IBD and Lymphoma. This can be accomplished using either laparoscopic techniques or open abdominal surgery. Laparoscopic techniques have been well described for organ biopsy. These techniques are minimally invasive and well suited for tissue procurement, however, laparoscopy is not yet readily available as a diagnostic tool in most small animal clinics. Surgery on

the other hand is an excellent way to obtain liver, pancreatic and intestinal biopsies. In addition to biopsy the liver should be cultured as well as bile aspirates for culture and cytology. We also currently culture the pancreas as well during laparotomy. Intestinal Biopsy: One can obtain intestine using several techniques. A full thickness biopsy allows the pathologist to porovide the most accurate diagnosis. When taking an intestinal biopsy, the easiest way to guarantee you will get an adequate size, full thickness piece of intestine is to use a brand new 4mm or 6mm skin punch biopsy instrument. The skin punch is placed on the antimesenteric border of the proposed segment of intestine and ‘drilled’ through all layers of intestine until the biopsy punch can be felt to enter the lumen of the intestine. The skin punch is removed and the biopsy retrieved from the shaft of the skin punch biopsy. This technique is particularly useful for ileal biopsy as it is easy to biopsy between the mesenteric and antimesenteric vessels. Transverse closure of the biopsy site is recommended to eliminate the possibility of lumen compromise. The biopsy site is closed using a simple interrupted or simple continuous suture pattern. 3-0 or 4-0 monofilament absorbable suture with a swaged-on sharp taper or taper-cut (penetrating point) needle is recommended. Care is taken to ensure that at least 3 mm bites are taken into the intestine and the sutures are no more that 2-3 mm apart. This is Dr. Seim’s preferred technique for intestinal biopsy. An alternate technique for intestinal biopsy is to make a 2-3 mm long incision on the antimesenteric border of the intestinal segment. A #11 or #15 BP scalpel blade is used to penetrate the intestinal wall. The blade is withdrawn to create a 2-3 mm long incision. A second parallel incision is made 1 – 2 mm from the original incision. A DeBakey forcep is used to grasp one end of the parallel incisions, a Metzenbaum scissor is used to cut out the piece of intestine. The surgeon should be careful not to crush the specimen with forceps. Only handle one end of the specimen while excising the biopsy specimen. If excessive trauma is created during biopsy, the pathologist may not be able to determine if the pathology is real or surgically created. The excised piece of intestine is examined closely to ensure that all layers have been included in the specimen. The biopsy site is closed using a simple interrupted or simple continuous suture pattern. 3-0 or 4-0 monofilament absorbable suture with a swaged-on sharp taper or taper-cut (penetrating point) needle is recommended. Care is taken to ensure that at least 3 mm bites are taken into the intestine and the sutures are no more that 2-3 mm apart. Complications associated with multiple intestinal biopsies are rare. Complications in patients undergoing intestinal surgical procedures are generally related to the surgeon’s technical ability and not the patient’s preoperative status. Lymph node biopsy: All lymph nodes are encased in a layer of peritoneum. When performing a lymph node biopsy it is best to tent the peritoneal covering with forceps and incise it with metzenbaum scissors. The peritoneum is then gently dissected off the lymph node. The exposed lymph node is biopsied using a #15 or #11 scalpel blade. Generally, a thin section of lymph node is ‘filleted’ off and placed in a moistened gauze sponge. The peritoneum covering the remaining lymph node is sutured to create suture pressure to help control surface hemorrhage.

Liver Biopsy: Surgical biopsies obtained during exploratory laparotomy are described here. The simplest method is performed by cutting a strip of liver parenchyma 5 to 6 mm thick along the border of the liver lobe. Excessive bleeding is rarely a problem with this technique; hemorrhage is controlled via cautery or direct pressure. Diffuse liver disease must be present if this method is to be diagnostic. A second technique involves placing an encircling ligature around a pedicle of liver tissue. As the ligature is tightened, it cuts through the hepatic parenchyma, ligating hepatic vessels and bile ducts. This technique, widely known as the Guillotine technique, has been criticized for leaving excessive amounts of devitalized parenchyma. This can be avoided by inserting scissors through the cut parenchyma and cutting hepatic vessels and bile ducts just distal to the ligature. This method requires the presence of diffuse liver disease to obtain a diagnostic biopsy unless the lesion is present in the distal aspect of the liver lobe. More localized abnormalities can be biopsied by wedge resections or partial lobectomy. Wedge resections may be performed by placing a row of overlapping, full-thickness, interrupted mattress sutures of 0 or 2-0 Maxon or Biosyn along each side of the wedge to be removed; these sutures should commence at the edge of the liver lobe and meet proximally to form a “V”. The sutures should be tied so as to compress the liver slightly but not cut into liver parenchyma. The wedge of tissue to be removed is incised about 5 mm from the suture line. Alternatively, the wedge may be removed prior to tightening the mattress sutures; preplaced mattress sutures are then gently tied with enough tension to control bleeding. An alternate technique for use in patients with diffuse fibrotic liver disorders is performed by penetrating the affected liver lobe with a straight mosquito hemostat. The hemostat tip is placed on the surface of the liver lobe to be biopsied and gently plunged through the liver lobe until the tip of the hemostat is seen penetrating through the opposite side of the liver. The jaws of the hemostat are opened just wide enough to accept a piece of 2-0 or 3-0 Maxon or Biosyn suture. The suture is doubled on itself, the loop is passed into the jaws of the hemostats, and the loop pulled through the liver lobe. The exiting loop is cut leaving two strands of suture coursing through the liver lobe. Each strand is tied individually to “cut” through the liver. A “V” wedge is cut through the liver when both strands of suture have been tied. A number 15 BP scalpel blade is used to cut the V-shaped liver biopsy wedge from the sutures. Pancreatic Biopsy: Samples from the pancreas should be obtained in all suspected triaditis cases. The old wive’s tale stating “don’t touch the pancreas” needs to be put to rest in veterinary medicine. Gentle manipulation and biopsy of the pancreas is a predictably successful procedure with almost no incidence of postoperative pancreatitis. Biopsy of the pancreas is performed in a similar manner as biopsy of the liver. In patients that have diffuse pancreatic disease, a segment of the right or left limb of the pancreas is identified. An encircling ligature of 3-0 Biosyn is placed around the pedicle. As the ligature is tightened, it cuts through the pancreatic parenchyma, ligating vessels

and pancreatic ducts. The distal pedicle of pancreas is carefully removed with a number 15 BP scalpel blade or metzenbaum scissors. Care is taken to avoid cutting the suture. Treatment of IBD It is important that the clinician formulate a treatment plan based on a correlation of clinical course, laboratory and gross findings, and histologic findings (considering both cellular infiltrate and morphology) rather than relying on histologic changes alone. Since food sensitivities can be a cause of IBD, dietary trials are an essential part of both the diagnostic and therapeutic strategy, utilizing hydrolyzed protein diets and novel protein diets and treating each patient as an individual (i.e., there can be variable responses to specific diets varying from patient to patient). Regarding pharmacotherapy, while corticosteroids have long been considered the cornerstone of treatment for idiopathic inflammatory bowel disorders, antimicrobial agents may play a role as well. Bacteria have been implicated in the pathogenesis of IBD. Guidelines for corticosteroids in cats with IBD are as follows. Mild to moderate cases of IBD often respond to prednisolone (preferred over prednisone in cats) at a starting dose of 1 to 2.2 mg/kg divided twice daily for two to four weeks followed by a gradual decline in 50% increments at two week intervals. Cats with inflammatory changes graded as mild usually respond quite well to the lower dose and alternate day or every third day treatment can often be achieved by two to three months. Occasionally treatment can be discontinued altogether by three to six months. If biopsies reveal disease that is moderate to severe a prednisolone dose of 2 to 4 mg/kg divided twice daily is used in cats for the first 2 to 8 weeks or until clinical signs resolve. This dose of corticosteroid is usually well tolerated in cats. In some cases a dose of 1 to 2 mg/kg per day may be necessary long term (months to years) to maintain clinical remission. Use of combination drug therapy may also be required at the outset to control clinical signs and prevent progression of the disease (e.g., metronidazole or tylosin plus prednisolone). Cats with hypoproteinemia and histologic changes graded as severe often respond quite well when an aggressive therapeutic course is undertaken. Budesonide is a glucocorticoid that represents an alternative for management of IBD in dogs and cats, especially in severe cases that have proven to be refractory to prednisolone, metronidazole, azathioprine, chlorambucil, tylosin, and dietary management; or that are intolerant of the corticosteroids discussed above. Budesonide is one of a group of novel corticosteroids that have been in development for use in humans in an attempt to make available alternative preparations that will help limit toxicity associated with corticosteroid use. Budesonide undergoes high first pass metabolism in the liver and 90% is converted into metabolites with low corticosteroid activity. It has minimal systemic availability. The potential for typical corticosteroid side effects is significantly reduced as a result of decreased bioavailability and the resulting limited systemic exposure, which makes this a particularly attractive drug for use in humans and animals that are poorly tolerant of

other corticosteroids. Budesonide also has a high receptor-binding affinity in the mucosa. It has been referred to as a “locally acting” corticosteroid. Therapeutic results with budesonide have been promising in humans with Crohn’s disease, collagenous colitis and lymphocytic colitis, ulcerative colitis, either when administered as a retention enema or in oral form, and primary biliary cirrhosis. Budesonide has been used by some veterinary clinicians in recent years to treat IBD in dogs and cats. Dose recommendations vary. In humans, a range of 6 mg to 9 mg per day has been used during initial therapy. In general, budesonide is administered to cats at 1 mg administered once per day (this dose level is prepared at a compounding pharmacy). Budesonide can be used in combination with other drugs. Since cats tolerate corticosteroids very well, there is little indication to use budesonide as initial therapy for IBD. However, this may be a very attractive option for use in diabetic cats that also have IBD, or in patients where conventional therapies have not been sufficiently effective. Potential adverse effects include PU/PD, when budesonide is used at the high end of the dose range, and GI ulceration. These reactions have been observed in some human patients. These problems would be more likely to occur in dogs than in cats. It appears to be very safe when used at the levels listed above. When combination therapy is indicated metronidazole is usually the first choice to be used in conjunction with prednisolone. Metronidazole’s mechanism of action includes an antiprotozoal effect, inhibition of cell-mediated immune responses, and anaerobic antibacterial activity. A dosage of 10 to 20 mg/kg two times daily is used for IBD. Ideally, at least several months of metronidazole therapy is given once it is started. In some cats with severe disease long term consecutive use or one to two month cycles of treatment may be required. Side effects to metronidazole at this low dose are uncommon in cats. Occasionally nausea or vomiting may be seen. If a client is unable to successfully administer oral medications, methylprednisolone acetate (Depo-Medrol) can be used as sole treatment for cats with mild to moderate IBD or as adjunctive therapy when oral prednisolone and/or metronidazole are used as the primary treatment and flare-ups of clinical signs occur. Consistent control of clinical signs in cats with moderate to severe IBD is more difficult to maintain when methylprednisolone acetate is used alone, however. It is recommended that sole use of methylprednisolone acetate be reserved for situations in which the owner is unable to consistently administer tablet or liquid prednisolone preparations. Initially 20 mg is given subcutaneously or intramuscularly and is repeated at 2-week intervals for 2 to 3 doses. Injections are then given every 2 to 4 weeks or as needed for control. If remission cannot be maintained with use of corticosteroids and metronidazole then chlorambucil (Leukeran) should be used. Azathioprine was used more in the past but it

has been largely supplanted now by chlorambucil. Chlorambucil is an alkylating agent. Alkylating agents alter DNA synthesis and inhibit rapidly proliferating cells. Chlorambucil is administered initially at 0.1 to 0.2 mg/kg/day in conjunction with prednisolone at 2.2 mg/kg/day. The small pill size of chlorambucil (2 mg) allows for easy dosing. Most cats receive one-half tablet (1 mg) per day. Various dosage schedules for cats have been published. An alternate schedule is 0.15 to 0.3 mg/kg every 72 hours. Toxicities are uncommon in cats but may include anorexia, vomiting, and diarrhea, but these problems generally resolve rapidly when chlorambucil is reduced from daily to every other day administration. Bone marrow suppression is possible but uncommon, and is mild and rapidly reversible when it does occur. Once the desired clinical response is achieved, chlorambucil is gradually tapered over several months while prednisolone is continued as the primary maintenance drug. Cyclosporine is another immunosuppressive drug that can be used in management of IBD. Cyclosporin inactivates calcineurin phosphorylase in T cells, preventing transcription of interleukin-2 (IL-2) as well as other cytokines. Cyclosporin inhibits activation of T cells, natural killer cells, and Langerhans (i.e., antigen-presenting) cells. Suppression of the Th1 or Th2 response induces antigen tolerance. The dose is 5 mk/kg once daily. Once sufficient response is achieved the dosage interval can be reduced to administration of a full dose every 48 hours and subsequently even further, on an individual patient basis. Cobalamin therapy in cats: Significant tissue level cobalamin deficiency is present in some animals with GI disease. This is usually secondary to reduced cobalamin absorptive capacity. It is essential that all cats with any form of GI disease (including involvement of liver, stomach, pancreas, intestines) have a serum cobalamin level run to determine if the patient is hypocobalaminemic. Response to therapy will be limited if low cobalamin levels are not resolved. The reference range for cobalamin in cats is 290-1500 ng/L. Therapy is given if the value is less than 500 ng/L (i.e., in the low part of the reference interval; donâ&#x20AC;&#x2122;t wait until the level drops below the low end point of the reference range). Therapy involves administering injectable cobalamin at the following schedule for cats: 250 ug subcutaneously once a week for 6 weeks, then every 2 weeks for the next 6 doses, then dose monthly. Most generic cobalamin preparations contain 1 mg/ml (1000 ug/ml). It is important to note that multi-vitamin and B-complex injectable formulations contain significantly lower concentrations of cobalamin and they also cause pain when injected. Therefore, it is recommended that these preparations not be used for cobalamin supplementation. Unless the intestinal disease is totally resolved, long-term and perhaps lifelong supplementation with cobalamin may be necessary. The frequency of injections on a long-term basis is determined by regular measurement of serum cobalamin concentration. Because dietary allergens may play a role in the cause if IBD, specific dietary therapy may be beneficial. Often, moderate to severe degrees of IBD are either temporarily responsive or only minimally responsive to careful dietary manipulations. However,

long term control of IBD with as minimal a drug administration schedule as possible may be aided by specific dietary management. This should be started as soon as a diagnosis is made and continued as drug therapy is decreased later. Feed elimination (novel protein) or hydrolyzed protein diets. Chicken, duck, lamb, fish, or venison based diets are often tried initially. Elimination diets have been found to be very beneficial in cats. Poor responses to treatment of cats with IBD usually result from: 1. Inadequate initial or long-term maintenance corticosteroid dosage in cats with more severe forms of IBD (moderate t severe disease). 2. Failure to use ancillary medications (metronidazole, chlorambucil, cyclosprinetylosin) in cases where disease is moderate to severe. 3. Failure to recognize and treat a concurrent condition (e.g., gastric hypomotility disorder that may either be secondary to IBD or idiopathic in nature, hyperthyroidism, parasitism [e.g., Giardia, Cryptosporidium], Clostridium perfringens enterotoxicosis, cholangitis/cholangiohepatitis, chronic pancreatitis). 4. Treatment for only small intestinal inflammatory disease when colitis is present as well. Some cats with concurrent IBD and colitis may show minimal or no clinical signs of colitis. 5. Failure to recognize and treat low body cobalamin levels (measure serum cobalamin). 6. Failure to identify an effective diet. 7. Poor client compliance

What If Biopsies are Not Definitive for Either IBD or Small Cell Lymphoma? It can be difficult to definitively differentiate benign IBD from small cell intestinal lymphoma, even when full thickness intestinal biopsies are obtained. If the biopsies were obtained via endoscopy, one option is to proceed to exploratory laparotomy to obtain full thickness samples. However, this is not practical in some cases and involves a more invasive procedure and more expense. Further, there is no guarantee that the differentiation can be made even when full thickness samples are obtained. Another option that is employed more commonly now is to perform special tests to help differentiate benign IBD from low-grade, small cell lymphocytic malignant lymphoma. Specific immunohistochemical techniques can be done to identify populations of malignant B and T lymphocytes (i.e., phenotyping) and molecular (PCR) testing is done for clonality. Clients should be given the option of ordering these additional tests if the pathologist indicates on the initial histopathology interpretation that the differentiation canâ&#x20AC;&#x2122;t be made definitively between IBD and lymphoma. If the client declines to have the additional tests performed, the clinician then needs to decide whether or not to just go ahead and treat for the disease that poses greater concern, i.e., lymphoma. Low grade small cell lymphoma is often treated with the combination of prednisolone and chlorambucil (see later discussion on treatment details in the next section).

Treatment of Intestinal Lymphoma in Cats Lymphoma is the most common feline neoplasm. It is also the most common form of gastrointestinal neoplasia in cats. Gastrointestinal lymphoma is often referred to as either well differentiated (low grade or lymphocytic), poorly differentiated (high grade, lymphoblastic, or immunoblastic), and intermediate (or mixed). Endoscopy has been shown to be a very useful modality for diagnosis of intestinal lymphoma in cats, especially when multiple biopsies are obtained using proper technique and instruments that can procure adequate size tissue samples. Immunohistochemical stains are beneficial for differentiating IBD from intestinal lymphoma in cases where it is difficult for the pathologist to distinguish between the two. Full thickness intestinal biopsies may be required in a very limited number of cases in order to establish the correct diagnosis. Many cats respond favorably to treatment for intestinal lymphoma, especially with the low grade or chronic lymphocytic type. Clinical signs can be very similar to cats with IBD. Therefore, it is strongly recommended that cats with chronic GI signs undergo a biopsy procedure as early as possible, so that the correct diagnosis can be established and the best course of therapy be made available for each individual cat. Biopsies should be obtained from both the upper and lower (ileum) small bowel. Multi-agent chemotherapy is recommended for all cats with GI lymphoma. Surgery is done only if there is an isolated mass that is causing some degree of luminal obstruction. Survival times in excess of 12 to 18 months are not unusual. In some cats the response is somewhat shorter (three to six months). The prognosis for longer survival time is much better if the diagnosis is made before clinical signs become chronic and debilitation results. One study from years back reported excellent results in cats with chronic lymphocytic lymphoma using a protocol of prednisone (10 mg PO per cat per day) and chlorambucil (Leukeran) and this report changed the way we managed cats with the more recently identified small cell lymphoma form. Chlorambucil was administered at a dosage of 15 mg/m2 PO, once every day for 4 days, and repeated every 3 weeks (Note: prednisolone is used routinely at this time, rather than prednisone, in cats). Sixty-nine percent of the cats with lymphocytic lymphoma treated with this regimen achieved a complete remission. The median disease free interval for cats that achieved complete remission was 20.5 months (range, 5.8-49 months). The median survival for all cats with lymphocytic lymphoma treated with chemotherapy was 17 months (range, 0.33-50 months). Cyclophosphamide (Cytoxan) was used for rescue in some of the cats that were entered in this protocol (225 mg/m2, PO, every 3 weeks). For further reference on this protocol, see Richter,K: Feline gastrointestinal lymphoma, ACVIM Proceedings 2001, p. 547-549. Since that early report, other dosage regimens for chlorambucil have been established. These are easier guidelines for clients to follow than the pulsed schedule. Currently I recommend either of these schedules: 1. Administer chlorambucil 2 mg every 48 hours, or

2. Chlorambucil 6 mg/m2 every 48 hours 3. For smaller cats or for those who do not tolerate chlorambucil as well, the dose frequency is reduced to every 3 days The protocol that I have used most often for cats with the more aggressive lymphoblastic form of GI lymphoma was originally published by Cotter in 1983. Dosage levels have been modified slightly since that time. This protocol utilizes cyclophosphamide, oncovin, and prednisolone (COP). This protocol can be easily managed in any practice setting. Vincristine is administered intravenously at a dose of 0.5-0.75 mg/m2 once weekly for 4 consecutive weeks and then once every 3 weeks. The initial doses are often decreased by approximately 25 percent for cats that are inappetent or debilitated. If well tolerated the dose can then be gradually increased. Care is taken to ensure that none of the vincristine is given extravascularly. The average volume that is administered is quite low (0.1 to 0.15 ml for many cats, using a vincristine concentration of 1 mg/ml). Cyclophosphamide is given orally at a single dose of 225 mg/m2 every 3 weeks (50 mg tablets are used with dosage adjusted to the nearest 25 mg on the low side of the calculated dose). Prednisolone is given orally at 10 mg per cat per day. Although cyclophosphamide and vincristine can be given on the same day I often prefer to have the owner administer the cyclophosphamide 2 to 3 days after the oncovin. A CBC is done several times during the first month and then every 3 weeks to be sure that adequate granulocytes are present before treatment. At least 3,000 granulocytes/ul must be present before cyclophosphamide is given. If the granulocyte count drops to less than 1,000/ul 5 to 7 days after cyclophosphamide, the dose for subsequent treatments is reduced by 25 percent. The highest non-toxic dose is most likely to result in the greatest tumor cell kill. The COP protocol is generally well tolerated, although side effects may occur and dosage or interval adjustments may be necessary. Side effects of COP in cats may include anorexia, vomiting, lethargy, and severe tissue irritation if any vincristine is given extravascularly. Also, the haircoat may become thinner, but complete hair loss does not occur. Cats do tend to lose whiskers. Cats should be carefully observed for sepsis especially during the induction phase. Prophylactic antibiotics are not indicated, but any infections that occur should be treated aggressively. Advantages of this protocol include hospital visits at only 3 week intervals after the first 4 weeks, lower cost to the owner, and a treatment interval that allows recovery of normal cells between treatments. I would like to emphasize that with careful monitoring and use of a dosage schedule that is tailored to each individual cat few problems are encountered It is our general practice to encourage owners of most cats with GI lymphoma to pursue treatment that includes chemotherapy. Nutritional and metabolic support are also important. If inappetence is a problem cyproheptadine can be administered as an appetite stimulant (1 to 2 mg orally every 12 to 24 hours) on an as needed basis (long-term if necessary). Mirtazapine is another appetite stimulant that can be used (one-fourth of a 15 mg tablet every three days). Intermittent vomiting, nausea, and inappetence is managed with maropitant (Cerenia) administered at 4 mg for most cats once orally daily as long as it is needed. If there is concurrent renal disease with azotemia or if dehydration is a problem owners are taught how to administer subcutaneous fluids at home (e.g., lactated Ringerâ&#x20AC;&#x2122;s 100 to 150 ml every 24 hours to 48

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hours, based on each individual cat’s needs). Special attention is given to ensuring that low cobalamin levels are addressed, if serum tests indicate that hypocobalaminemia is present. Rarely chemotherapy can be discontinued after one year. This is done only if follow-up endoscopic intestinal biopsies indicate that there is no remaining lymphoma. Most cats remain on treatment for the remainder of their lives. If chemotherapy is poorly tolerated and reduced dosages and increased intervals between treatment times are unsuccessful in adequately decreasing side effects chemotherapy should be suspended. Prednisolone should be continued however because it may help maintain remission for a period of time. Doxorubicin (Adriamycin) can also be used in cats. For clinicians inexperienced in administering chemotherapy, or who have not treated many cats with intestinal lymphoma, it is recommended that a veterinary oncologist or internist be consulted for guidance on protocol selection and ongoing management. Many cats with intestinal lymphoma can be managed successfully for some period of time!

References 1. Baez JL, Hendrick MJ, et al. Radiographic, ultrasonographic, and endoscopic findings in cats with inflammatory bowel disease of the stomach and small intestine: 33 cases (1990-1997). J Am Vet Med Assoc, 1999; 215:349-354. 2. German AJ. Inflammatory bowel disease. In Bonagura JB and Twedt DC (eds), Current Veterinary Therapy XIV. Elsevier, St. Louis, 2009. pp 501-506. 3. Grooters AM, Biller DS, et al. Ultrasonographic appearance of feline alimentary lymphoma. Vet Radiol Ultrasound, 1994; 35(6):468-472. 4. Jergens AE, Willard MD, Day MJ. Endoscopic biopsy specimen collection and histopathologic considerations. In Tams TR and Rawlings CA (eds), Small Animal Endoscopy. Elsevier, St. Louis, 2011. Pp. 293-309. 5. Penninck DG, Moore AS, Tidwell AS, et al. Ultrasonography of alimentary lymphosarcoma in the cat. Vet Radiol Ultrasound 1994; 35:299–304. 6. Tams TR and Webb CB. Endoscopic examination of the small intestine. In Tams TR and Rawlings CA (eds). Small Animal Endoscopy. Elsevier, St. Louis, 2011. pp. 173-215. 7. Scott KD, Zoran DL, Mansell J, et al. Utility of endoscopic biopsies of the duodenum and ileum for diagnosis of inflammatory bowel disease and small cell lymphoma of cats. J Vet Intern Med 2011; 25:419-425. 8. Zwingenberger L, Marks SL, Baker TW, and Moore PF. Ultrasonographic evaluation of the muscularis propria in cats with diffuse small intestinal lymphoma or inflammatory bowel disease. J Vet Intern Med 2010; 24:289–29.

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INFLAMMATORY BOWEL DISEASE (IBD) IN DOGS â&#x20AC;&#x201C; DIAGNOSIS AND THERAPY Todd R. Tams, DVM, DACVIM Chief Medical Officer VCA Los Angeles, CA Introduction Inflammatory bowel disease (IBD) is not a specific diagnosis, rather it is a histological description of a syndrome resulting from a host hypersensitivity response to antigenic stimuli. In IBD there is an increase in the inflammatory cell population in the intestinal mucosa. The predominant inflammatory component can be lymphocytic-plasmacytic (most common type), eosinophilic, neutrophilic, or granulomatous. Primary causes of intestinal inflammation that should be considered include parasites, bacteria (specific agents or bacterial overgrowth), fungal disorders (e.g., Histoplasma, pythiosis), immune-mediated diseases, and food sensitivities. Many cases of IBD are likely idiopathic in nature. A presumptive diagnosis of IBD is made on the basis of history, physical exam and elimination of other disorders by laboratory tests and other studies such as radiography and ultrasonography. A definitive diagnosis can be made only by intestinal biopsy. Clinical Course The clinical course of inflammatory bowel disease can be characterized by diarrhea only, vomiting only, or both vomiting and diarrhea. Associated clinical signs that may also be seen, either singly or in combination, include weight loss, listlessness, borborygmus, flatulence, and abdominal pain. In some patients, inappetance may be the only sign, although this is more common in cats than dogs. Inflammatory bowel disease is a common cause of chronic vomiting in dogs. Vomiting may be reported as a problem of recent onset or it can be an intermittent problem occurring over a period of several months or years before it becomes more frequent and severe. It is important for the clinician to recognize that vomiting may be the only major sign that occurs in a patient with inflammatory bowel disease. Gastric hypomotility can occur secondary to an infiltrative bowel disease such as IBD. In some dogs with IBD, chronic intermittent or chronic intractable diarrhea is the major clinical sign. In these cases, the clinician must determine if the diarrhea is resulting primarily from small bowel or large bowel involvement, or is a mixed component of both large and small bowel. Although inflammatory bowel disease is not breed specific, the Sharpei breed requires special consideration because they can develop a severe type of IBD. Most Sharpei dogs with IBD will present with a ravenous appetite, chronic diarrhea and weight loss. They often have intestinal dysbiosis (bacterial overgrowth) and other

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intestinal problems as well. Shar-Peis with diarrhea, even for short durations of 3 to 4 weeks, due to IBD seem to be at increased risk of developing hypoproteinemia. Early clinical investigation in these patients should always include a complete blood count and complete biochemical profile. If clinical investigation of a patient with chronic vomiting and/or diarrhea shows decreased albumin and globulin levels (panhypoproteinemia), IBD of a moderate to severe degree should be one of the leading differentials. Lymphangiectasia, intestinal lymphoma, histoplasmosis, and pythiosis should also be considered. There is a regional geographic distribution with the latter two conditions. IBD is by far the most common cause of protein losing enteropathy in dogs. The presence of panhypoproteinemia indicates that the degree of disease is significant and likely chronic in nature. Many dogs with IBD will not develop hypoproteinemia, but for those that do, hypoproteinemia heralds severity and indicates that the disease is advancing. Steps to establish a definitive diagnosis should be expedited and an aggressive treatment regimen will likely be necessary. Diagnosis A presumptive diagnosis of canine inflammatory bowel disease is made on the basis of history, physical examination and the elimination of other disorders through laboratory tests and radiographic studies. The most important diagnostic procedure for a definitive diagnosis of IBD, however, is biopsy. Baseline laboratory tests in dogs with chronic vomiting or diarrhea should always include a complete blood count, biochemical profile, urinalysis (as a means of assessing renal function and to evaluate for proteinuria), and fecal examination for parasites. Baseline tests are frequently normal or negative, but abnormalities that may be identified include mild nonregenerative anemia (anemia of chronic inflammatory disease); leukocytosis (20,000 to 50,000 cells/ul) without a left shift (suggests active chronic inflammatory disease); eosinophilia (mild to dramatic increase) in some dogs with eosinophilic enteritis; and hypoproteinemia. Any abnormalities of liver enzymes should also be noted. Testing for parasites in dogs with diarrhea is best accomplished using zinc sulfate flotation with centrifugation. This is an excellent test medium for detection of nematode parasites as well as Giardia. Zinc sulfate flotation with centrifugation is superior to flotation with sodium nitrate, or flotation with zinc sulfate without centrifugation. Testing for Giardia-specific antigen in feces is also an excellent means of diagnosing giardiasis. In fact, Giardia antigen testing is very sensitive and can identify infections that may be missed on one or two zinc sulfate centrifugation tests with centrifugation or where there is incorrect interpretation of the identity of cyst structures (a common error in clinical practice). A fecal assay for Clostridium perfringens enterotoxin should also be done. Although exocrine pancreatic insufficiency (EPI) is uncommon in dogs, it is always a good idea to do a trypsin like immunoreactivity (TLI) test on dogs with chronic

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diarrhea to definitively rule out (EPI). Serum cobalamin (B12) and folate assays may be useful in evaluating dogs with chronic diarrhea, especially for intestinal dysbiosis (formerly referred to as intestinal bacterial overgrowth) and clinical hypocobalaminemia. Subnormal serum cobalamin concentrations may occur in association with small intestinal disease, EPI, dysbiosis, and inherited selective defects in cobalamin absorption. Serum folate concentrations may be increased in dogs with dysbiosis and decreased with infiltrative small bowel diseases. A definitive diagnosis can be made only by biopsy, the single most important diagnostic procedure in the evaluation of chronic intestinal disease. Biopsy should be done to confirm diagnosis and determine type and extent of involvement. It is especially useful in determining treatment and prognosis. Endoscopic and surgical biopsies are discussed in a subsequent section. Diagnostic Imaging of the Intestinal Tract (Diagnostic Imaging section contributed by Dr. David S. Biller, DACVR, Kansas State University) Normal Radiographic Anatomy of the Small Intestine The small intestine should be evaluated for margination (serosal surface definition). The margin should be smooth. It will normally be visible due to fat in the serosa except when the animal is young (< 6 months) or emaciated or if abdominal fluid or cellular infiltrates are present. The normal diameter of the small intestine in dogs is < 2â&#x20AC;&#x201C;3 rib widths, or less than the dorsoventral dimension of the second lumbar vertebral body. The small bowel should be evenly distributed throughout the abdomen, occupying space not taken up by other organs. As organomegaly occurs, whether normal (distended stomach or urinary bladder) or abnormal (e.g., mesenteric lymphadenopathy, pancreatic enlargement, splenic mass), the intestine will be displaced. The direction helps to determine the differentials for the mass causing the displacement. In obese cats, it is common for the intestines to be localized in the ventral abdomen to the right of midline. The small bowel should have a smooth, continuous, curved appearance. It is often necessary to have contrast studies (upper GI series) to identify normal or abnormal shape or diameter of small bowel. The radiopacity of the bowel loop is dependent on whether it is fluid-filled, gas-filled, or filled with a combination of fluid and gas. Fluid-filled loops of bowel appear as white rope-like structures. Gas-filled loops appear as black, thin-walled tubes. A small amount of gas above fluid appears as a narrow, radiolucent band with an apparent thickening of the bowel wall. A larger volume of gas reflects wall thickness more accurately and therefore bowel wall thickness should never be evaluated on survey films but only with use of contrast (whether negative or positive).

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In dogs, barium should enter the duodenum in 13–20 minutes, the jejunum in 30 minutes, the jejunum and ileum in 60 minutes, and the ileocolic junction in 90–120 minutes. Barium should clear the upper GI tract and enter the ileum and colon in 3–5 hours. The appearance of the mucosa or wall of the small bowel is best evaluated using positive contrast material. The mucosa should appear as a smooth, even surface or as a finely fimbriated edge. This fimbriation is due to barium dissecting between groups of aggregated villi. In normal young dogs, the mesenteric border of the duodenum has numerous or single, usually square or conical depressions, in the bowel overlying lymphoid follicles. These are pseudoulcers and considered normal. They are not seen in cats. Abnormal Anatomy of the Small Intestine on Survey Radiographs Ileus is an obstructive condition of the intestine and is either mechanical or functional. Mechanical ileus is also referred to as “dynamic” (or obstructive) ileus. It is usually simple and nonstrangulating. The radiographic signs may be influenced by the degree, location, and duration of obstruction. Dilatation of small intestine secondary to mechanical obstruction results from swallowed air and saliva and accumulation of mucosal secretions in the digestive tract. Functional ileus, also referred to as paralytic or adynamic ileus, can be localized or generalized and may be a sequelae to mechanical ileus. The stages of development of functional ileus include muscle fatigue allowing stretching of the intestine, muscle ischemia secondary to stretching, and muscle necrosis. Functional ileus has numerous causes, such as extrinsic (which tend to be more generalized) that include spinal cord injury, reflex to pain, peritoneal trauma or irritation, or vascular compromise, and intrinsic (which is most often regional). Intrinsic causes include edema, amyloidosis, and acute inflammation or enteritis. Survey radiographs of inflammatory bowel disease are usually normal or luminal fluid maybe increased. Abnormal Anatomy of the Intestinal Tract on Contrast Radiographs Intraluminal disorders usually appear as radiolucent areas surrounded by positive contrast medium. They often delay intestinal transit time and cause ileus proximal to their location. Intramural disorders should be evaluated with an upper GI series (positive contrast/barium). The following questions should be answered while evaluating the upper GI series: 1. whether the lesion projects into the lumen, causes a narrowing or constriction; 2. whether the lesion projects away from the lumen, causing an enlargement of the diameter of the lumen as a result of a defect in the bowel wall; 3. whether thickening and rigidity of the bowel wall, irregularity at the serosal or mucosal surfaces, or a combination of these changes has occurred.

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Radiographically, intramural disorders of the bowel may appear pedunculated, broad-based, smooth or irregular, and may expand the width of the bowel. Benign tumors tend to be smooth; malignant tumors tend to be irregular. The causes of intramural lesions include neoplasia, granuloma, abscess, scar, and hematoma. Inflammatory diseases of the small intestine (enteritis) tend to increase the rate of intestinal motility (i.e., reduced transit time). Chronicity and severe enteritis may cause irregularity of the mucosal surface; chronic enteritis may also decrease the width of the bowel lumen. Chronic and very severe enteritis can cause alterations or erosion of the mucosa. Barium studies of patients with severe/chronic inflammatory bowel disease may be characterized by the appearance of thumbprinting. Thumbprinting is described as irregularly arranged mural based indentations into the contrast column. Ultrasonography of the Normal Gastrointestinal Tract Until recently, ultrasonography was considered to be a poor choice for evaluation of the GI tract because of the ultrasonographic barrier caused by luminal gas. Over the past 5 years, however, it has been applied successfully in diagnosis of a number of GI disorders, including gastric and intestinal foreign bodies, intussusception, uremic gastropathy, chronic pyloric hypertrophic gastropathy, enteric duplication, and GI neoplasia. It has proven useful not only in the diagnosis of morphologic GI disease but also in the evaluation of GI function. Maximizing resolution by using a highfrequency transducer is critical in the examination of the GI tract. Fasting the animal before ultrasonography also improves the results of the examination. Normal Wall Thickness in Dogs Stomach 3-6 mm Duodenum 3-5 mm Jejunum 2-4 mm Ileum 2-4 mm Colon 2-3 mm Ta*Larger dogs have thicker walls. Ultrasonography enables differentiation of the layers of the stomach, which alternate in echogenicity. Under optimal conditions, five separate layers can be identified. They are the luminal–mucosal interface (hyperechoic), mucosa (hypoechoic), submucosa (hyperechoic), muscularis (hypoechoic), and subserosa–serosa (hyperechoic). The submucosa and subserosa–serosa are hyperechoic because of the presence of relatively more fibrous connective tissue. The mean number of peristaltic contractions in the stomach is 4–5 per minute. The ultrasonographic appearance of the GI lumen depends on its contents. In a collapsed, state the bowel lumen appears as a hyperechoic core (“mucosal stripe”) surrounded by a hypoechoic halo of bowel wall. This core represents mucus and small air bubbles trapped at the mucosal–luminal interface. When fluid is present in the bowel lumen, an anechoic area is present between the walls of the bowel that

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appears tubular in long-axis views and circular in short-axis views. Gas in the GI lumen causes a highly echogenic interface with reverberation artifact. The presence of fluid in the bowel lumen improves the sonographer’s ability to evaluate the mucosal and submucosal layers of the GI tract, whereas the presence of luminal gas hinders it. As with the stomach, the layers of the intestine alternate in echogenicity. Under optimal conditions, five separate layers can be identified: the luminal–mucosal interface (hyperechoic), mucosa (hypoechoic), submucosa (hyperechoic), muscularis (hypoechoic), and subserosa–serosa (hyperechoic). Real-time ultrasonography should be included in the examination of enteric motility. The mean number of peristaltic contractions in the intestine is 4–5 per minute. Contractions are not seen in the colon. Ultrasonography of the Abnormal Gastrointestinal Tract Ileus Both mechanical and paralytic ileus have been described as ultrasonographic findings. Mechanical ileus occurs proximal to an area of obstruction; paralytic ileus can be generalized (e.g., viral enteritis, hypokalemia) or focal (e.g., duodenitis secondary to pancreatitis). When ileus is present, the bowel appears dilated and fluid-filled and GI motility is decreased or absent. Inflammatory Disease With inflammatory bowel disease, the intestine may be normal on ultrasound examination. The measurement of the intestinal wall thickness by ultrasound is neither specific nor sensitive for diagnosing IBD. Changes, especially those of severe or chronic disease, have been reported as focal to diffuse thickening, altered echogenicity, poor intestinal wall layer definition, and mild enlargement of adjacent lymph nodes. Mucosal echogenicity may remain hypoechoic, appear hyperechoic with striations or hyperechoic with speckles and be associated with but nonspecific for IBD. Jejunal lymph node thickness of > 6 mm maybe consistent with IBD but nonspecific for the type of disease. Round, enlarged, hypoechoic LNs maybe more consistent with neoplasia, while inflammatory lymph nodes may be enlarged but tend to maintain their normal shape. The most common finding with inflammation is extensive and symmetric wall thickening with the layering retained. In comparison, neoplasia is usually localized with greater wall thickness and loss of normal layering. These categories can overlap, and therefore cytology or histopathology is required for definitive diagnosis. Acute enteritis or inflammatory bowel disease may demonstrate corrugation of the intestine on ultrasound examination. Intestinal Biopsy Techniques Endoscopic Biopsy: Endoscopy is a minimally invasive procedure in which multiple biopsies can be obtained and this procedure generally has greater client

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compliance than with surgery because it is less invasive and less expensive than exploratory abdominal surgical procedures. Endoscopy offers a means of examining the upper and lower small intestine, stomach, and colon. It is especially advantageous because biopsies can be obtained early in the course of the disorder, at a stage when a client will likely be reluctant to agree to an exploratory surgery for their pet. Endoscopy also offers significantly reduced risk to the patient with hypoproteinemia. The degree of intestinal changes noted on biopsy also provides useful guidelines for both type and duration of therapy that will be needed to control the specific disorder. Clinicians need to make sure they are taking an adequate number of endoscopic biopsy samples for accurate diagnosis. Even expert endoscopists report that in some cases one-fourth to one-third of the biopsies they take from a patient will have some degree of damage to the tissue that may preclude the samples from being useful or representative. Therefore, it is recommended that clinicians take 8 to 12 biopsy samples from the upper small intestine so that the pathologist will have enough tissue to work with. Also, it is recommended that both upper and lower GI endoscopy be done in dogs with chronic diarrhea. In this way biopsies from the ileum can be obtained by passing the endoscope along the full length of the colon and through the ileocolic orifice and into the ileum. When a pediatric diameter endoscope is used this is possible in most dogs over 4 to 5 kg. If the ileum can not be entered, it may be possible to obtain at least blind biopsies of the ileum by passing the endoscopic biopsy instrument through the ileocolic orifice with the endoscope tip positioned at the ileocolic sphincter area. Colon biopsies are always obtained as well during colonoscopy in order to evaluate for inflammation in the colon. Organ Biopsy via Laparoscopy or Laparotomy Organ biopsy is required to confirm canine IBD, and full-thickness samples procure tissue samples that will help the pathologist make the most accurate diagnosis. Full thickness intestinal biopsies can be accomplished by laparoscopic techniques or open abdominal surgery. Laparoscopic techniques have been well described for visceral organ biopsy. They are minimally invasive and well-suited for tissue procurement; however, laparoscopy is not yet readily available as a tool in most small animal general practice hospitals. Surgery on the other hand is an excellent way to obtain liver, pancreatic, and full thickness intestinal biopsies. In addition to biopsy, liver, pancreas and bile aspirates can be obtained for culture and cytology.

TREATMENT OF INFLAMMATORY BOWEL DISEASE Successful treatment of canine inflammatory bowel disease depends on accurate diagnosis. The presumed pathogenesis of IBD involves antigenic stimulation and an inflammatory response mediated by the mucosal immune system. Therefore, therapy should include the suppression of the inflammatory response which requires the use of pharmacologic therapy. Removal of any antigenic source of inflammation

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is also necessary, and that is where dietary therapy is important. Food allergens can be a causative factor in some animals with IBD. The goal of dietary management is to reduce the antigenic stimulation of the intestinal immune system. Drug Therapy For patients with mild IBD, diet alone may be the only treatment needed. If, however, pharmaceutical therapy is also indicated, steroids may be used at a range of 0.5 - 1 mg/kg, divided BID for two to four weeks. The dose is then gradually decreased at two to four week intervals, and an attempt is made to achieve alternate or every third day therapy by two to three months or so. Some patients with mild IBD will respond well to metronidazole therapy, without concurrent use of corticosteroids (see below). In moderate cases (based on biopsy changes and the patientâ&#x20AC;&#x2122;s overall condition), the steroid dosage should be higher (1.1 to 2.2 mg/kg per day for two to four weeks before an attempt to decrease the dosage is initiated). Moderate to severe and severe IBD cases are managed initially with prednisone at 2.2 to 3.3 mg/kg per day. Combination therapy is often used for dogs with moderate to severe IBD. Combination therapy includes prednisone and metronidazole, or in dogs with severe IBD and concurrent panhypoproteinemia (with a total protein level of 4.5 g/dl or lower) prednisone, metronidazole, and azathioprine are used concurrently. Some dogs do not tolerate corticosteroids very well. For example, Arctic breeds and Rottweilers frequently cannot tolerate very high doses for an appreciable period of time. In these breeds I generally start with conservative doses of steroids, usually no higher than 0.5 to 1 mg/kg total per day. This may still be too high for some dogs. Metronidazole is sometimes used concurrently from the outset. For patients exhibiting severe steroid hepatopathy (panting, severe PU/PD, lethargy, weakness, and sometimes a decreased appetite) steroids should be stopped completely for 36 hours to allow for adequate metabolism and clearance. Steroids can then be resumed at approximately 25 percent of the initial dose. If prednisone is still poorly tolerated at this lower level, try oral dexamethasone next (0.01 to 0.02 mg/kg per day initially). Some larger canine breeds do not tolerate prednisone well, but will often tolerate dexamethasone at 0.25 to 0.5 mg total, one to two times per day. Very large breeds such as Great Danes and others weighing 68 kg (150 lb) or more, will sometimes do well even on as low as 0.5 mg of dexamethasone, BID when there was initial difficulty in tolerating prednisone. In some cases, steroids simply cannot be used due to severe drug reactions in the patient and other drugs must be used. When a patient is either poorly responsive to corticosteroids when used as outlined above, or if there is poor tolerance, the next best options are to try either budesonide or cyclosporine. Cyclosporine is described further below. Budesonide is a newer corticosteroid for use in humans. Budesonide is a glucocorticoid that also represents an alternative for management of IBD in dogs, especially in severe cases

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that have proven to be refractory to prednisone, metronidazole, azathioprine, and dietary management; or that are intolerant of the corticosteroids discussed above. It is one of a group of novel corticosteroids that have been in development for use in humans in an attempt to make available alternative preparations that will help limit toxicity associated with corticosteroid use. Others include fluticasone propionate, tixocortol pivalate, and beclomethasone dipropionate. Budesonide undergoes high first pass metabolism in the liver and 90% is converted into metabolites with low corticosteroid activity. It has minimal systemic availability. The potential for typical corticosteroid side effects is significantly reduced as a result of decreased bioavailability and the resulting limited systemic exposure, which makes this a particularly attractive drug for use in humans and animals that are poorly tolerant of other corticosteroids. Budesonide also has a high receptor-binding affinity in the mucosa. It has been referred to as a â&#x20AC;&#x153;locally actingâ&#x20AC;? corticosteroid. Therapeutic results with budesonide have been promising in humans with Crohnâ&#x20AC;&#x2122;s disease, collagenous colitis and lymphocytic colitis, ulcerative colitis, either when administered as a retention enema or in oral form, and primary biliary cirrhosis. Budesonide has been used by some veterinary clinicians in recent years to treat IBD in dogs and cats. Dose recommendations vary. In humans, a range of 6 mg to 9 mg per day has been used during initial therapy. The following general recommendations have been made for dogs. In general, budesonide is administered to small dogs at 1 mg administered once per day. Medium size dogs receive 2 mg once daily. Large dogs receive a maximum of 3 mg once daily initially. Budesonide is available as a 3 mg capsule preparation and lower dosage forms are prepared by compounding pharmacists. Budesonide can be used in combination with other drugs. Potential adverse effects include PU/PD, when budesonide is used at the high end of the dose range, and GI ulceration. These reactions have been observed in some human patients. These problems would be more likely to occur in dogs than in cats. It appears to be very safe when used at the levels listed above. Metronidazole has both antibacterial and anti-inflammatory effects. It is very useful in treatment of IBD in dogs. In mild to moderate cases metronidazole alone may be sufficient to help control the intestinal inflammation. When used in combination with steroids metronidazole often allows for earlier reduction of the steroid doses. The dose of metronidazole for antibacterial and anti-inflammatory effect is 11 to 22 mg/kg BID. It is sometimes administered once daily to once every other day for maintenance therapy once the patient is deemed to be well under control but not yet able to be entirely without some form of drug therapy. Use of azathioprine is generally reserved for severe IBD cases. Azathioprine has a potent immunosuppressive effect. Although azathioprine can cause bone marrow suppression, marrow suppression is rare when azathioprine is dosed accurately.

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The canine dose is 2 mg/kg SID, orally. Azathioprine also has the potential to induce pancreatitis. Azathioprine has a lag phase of 3 to 4 weeks, so it should be instituted early once a diagnosis of severe IBD is made. Azathioprine is usually used for 3 to 9 months in dogs. Once adequate control is achieved, the daily dose is decreased by 50%, and subsequently alternate-day therapy is used. A complete blood count and platelet count should be run to monitor for evidence of anemia, leukopenia, or thrombocytopenia at 3 week intervals for the first 2 months of therapy and then once every several months. Many canine IBD patients are thought to have intestinal bacterial overgrowth as well, and they can often be helped with the use of antibiotics. The antimicrobial drugs used most commonly include metronidazole or tylosin. In some cases cephalosporins or enrofloxacin are used (not usually the first choice, however). Combination therapy with metronidazole plus enrofloxacin or metronidazole with tylosin is used in some cases, e.g., those with longer duration of signs or where there may be more significant patient compromise. In mild cases two to four weeks of antimicrobial therapy is frequently sufficient. If crypt abscesses are reported on the histopathologic exam antimicrobial therapy is used for a longer time in conjunction with appropriate anti-inflammatory therapy. Tylosin is a macrolide, bacteriostatic antibiotic that has activity against most grampositive and gram-negative cocci, gram-positive rods, and Mycoplasma. However, the gram-negative bacteria E. coli and Salmonella spp. are intrinsically tylosin resistant. Studies (Westermarck) have revealed that administration of tylosin leads to significant but transient changes in the composition of the small intestinal flora. It may be that tylosin promotes the growth of commensal bacteria whole suppressing deleterious bacteria. In addition to antimicrobial properties tylosin may also have anti-inflammatory The term â&#x20AC;&#x153;tylosin responsive diarrheaâ&#x20AC;? has been coined as a result of observations that dogs with nonspecific diarrhea will often respond to tylosin therapy. Some cases are intermittent or chronic in nature. Dose range is 7 to 20 mg/kg orally every 12 to 24 hours (administer BID initially). Use of other drugs may be indicated in some dogs with IBD. If large intestinal inflammation is present either metronidazole or 5-amino salicylic acid derivatives (sulfasalazine, osalazine, mesalazine) or both in combination will usually control large bowel diarrhea due to colitis. Corticosteroids are usually ineffective for controlling signs of large intestinal inflammation in dogs (although steroids are very effective for this purpose in cats). Other alternative therapies may include cyclophosphamide, chlorambucil, and cyclosporin. Omega 3 fatty acids (antiinflammatory effects) or vitamin E (antioxidant) may also be beneficial in some chronic cases. Cyclosporine: Cyclosporine A (cyA) has been shown to be effective in steroidresistant IBD in humans and also perianal fistula management in both humans and

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dogs. Other uses in dogs have included management of atopic dermatitis and sebaceous adenitis. A study was undertaken to evaluate the pharmacokinetics and clinical efficacy of oral cyA treatment in 14 dogs with steroid-refractory IBD (Allenspach K, et al). Patient assessment included determination of a clinical activity score to assess severity of clinical signs before and after treatment. The total number of infiltrating lymphocytes and T cells in duodenal biopsies obtained via endoscopy were also assessed before and after treatment. Improvement was noted in 12/14 dogs. There was a significant improvement in clinical activity score and a decrease in T cell numbers, implying that T cell lysis is a possible mechanism of action. Results from this study suggest that cyA is an effective option for managing some dogs with steroid refractory IBD. The anti-inflammatory effect of cyA in human IBD is believed to be due to suppression of activated T cells infiltrating the mucosa, thereby decreasing the amount of proinflammatory cytokines, and ultimately, the clinical signs of disease. The cyA dose used in the study of 14 dogs was 5 mg/kg SID. The sole therapy was cyA. Previous therapy had included immunosuppressive doses of steroids in all dogs (starting dose of prednisolone was 2.2 mg/kg/day, administered for a range of 6 to 14 weeks before the dose was decreased). Other drugs tried in most of the dogs included metronidazole (range of 2 to 38 weeks). There were transient adverse effects observed in 5 dogs, most of which occurred in the first 1 to 2 weeks of therapy, after which time they abated. Adverse reactions included vomiting and inappetence (4/14 dogs), and gingival ulceration and alopecia followed by hypertrichosis in 1 dog. A lag phase of 7 to 10 days has been seen in humans before there are obvious signs of clinical improvement, and a similar finding was observed in the dogs in the study reported here. The clinical efficacy study showed that cyA was effective in 11/14 of the dogs (78%). Nine dogs were considered complete responders after 10 weeks of treatment, 3 were partial responders, and 2 were nonresponders that had to be euthanized during the study because no clinical improvement was observed. Eight out of the 9 dogs that responded well initially were still doing well after 6 months to 2 years follow-up. One dog responded well for 14 weeks but then relapsed and declined with severe vomiting and was euthanized. Eight dogs were discontinued from cyA after 10 weeks of therapy. Three dogs were kept on therapy for 4, 6, and 36 months. These dogs had all shown significant improvement in clinical score but the owners elected to keep their dogs on therapy. Duration of Pharmacotherapy The duration of therapy that is required in dogs with IBD is quite variable. Patients with milder forms of IBD may need medical management for as little as 2 to 4 months. IBD in middle age to older dogs that is initially graded as moderate to severe can usually be managed quite successfully and can be maintained in remission but not often cured. However, in the authorâ&#x20AC;&#x2122;s (T. Tams) experience young dogs that are diagnosed and managed early enough rarely require long-term therapy

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(more than 1 to 2 years). In some young dogs (3 to 4 years of age or less) with severe lymphocytic-plasmacytic enteropathy and marked hypoproteinemia, therapy can be successfully discontinued as early as 9 months to 1 year. As a general clinical rule of thumb, an attempt can be made to discontinue therapy after 2 to 3 months of successful control on twice-weekly medication. If signs recur, medication is resumed on a daily basis for 7 to 14 days before a gradual reduction program is started. Dietary Therapy As was mentioned earlier, the goal of dietary therapy in IBD is to reduce the antigenic stimulation of the intestinal immune system. Many pet food companies today provide myriad information on adverse food reactions and offer many good diets from which to choose. Dogs with IBD should be fed divided feedings, two or three times per day. The two main categories of foods used in dietary trials are novel protein diets and hydrolyzed protein diets. A diet that is hypoallergenic is one that contains no additives or preservatives and has a single source of protein that is easily digestible. The protein source must be one that is "novel," meaning one that the dog has not eaten before. Examples of novel proteins now being used by pet food manufacturers include white fish, venison, rabbit, duck, salmon, catfish, and lamb. Manufacturers have been using lamb in their diets for many years now, so many dogs have eaten lamb containing diets. Dogs that have eaten lamb before should be tried on some other protein. It may be helpful to consider switching the initial novel protein to another source at six to eight weeks into the treatment course. When there is considerable inflammation and damage to the intestinal mucosa, the antigens that are in the new protein source can get absorbed and the animal may acquire an allergy to this protein. Switching them periodically could potentially alleviate this situation. The primary carbohydrate source used in hypoallergenic diets is either potato or rice. Treatment Failure An inadequate response to therapy is most frequently due to either incomplete diagnosis (i.e., the patient has more problems that have been diagnosed), the diagnosis is incorrect, or inadequate therapy is being administered (e.g., wrong drugs, or right drugs but incorrect doses). Veterinarians need to stress the importance of GI biopsy for dogs with disorders that do not resolve fairly early on therapeutic regimens which include dietary trials, antimicrobials, and management for any GI parasites that have been identified. In chronic cases, too often the empirical therapy route is tried for too long and ultimately the patient suffers for this approach. A thorough diagnostic approach will significantly increase the chances that therapeutic intervention will be successful. In dogs with IBD that are vomiting, a secondary gastric hypomotility problem should be considered, and gastric prokinetic therapy may prove beneficial. Sometimes anti-inflammatory medication doses are reduced too rapidly. It is better to use aggressive therapy, while carefully monitoring the patient, rather than be too conservative.

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References Allenspach K, Rufenacht S, Sauter S, Grone A, et al. Pharmacokinetics and clinical efficacy of cyclosporine treatment of dogs with steroid-refractory inflammatory bowel disease. J Vet Intern Med 2006; 20:239-244. German AJ: Inflammatory bowel disease. In Bonagura JD and Twedt DC, eds: Current Veterinary Therapy XIV, St. Louis, 2009, p. 501-506, Elsevier. Grooters AM, Leise BS, Lopez MK, et al. Development and evaluation of an enzyme-linked immunosorbent assay for the serodiagnosis of pythiosis in dogs. J Vet Intern Med 2002; 16:142-146. House AK, Guitian J, Gregory SP, and Hardie RJ: Evaluation of the effect of two dose rates of cyclosporine on the severity of perianal fistulae lesions and associated clinical signs in dogs. Vet Surg 2006; 35:543-549. Jackson HA: Hypoallergenic diets: principles in therapy. In Bonagura JD and Twedt DC, eds: Current Veterinary Therapy XIV, St. Louis, 2009, p. 395-397, Elsevier. Tams TR and Webb CB. Endoscopic examination of the small intestine. In Tams TR and Rawlings CA, eds: Small Animal Endoscopy, ed. 3, St. Louis, 2010, p. 173215. Tams TR. Chronic diseases of the small intestine. In Tams TR, ed: Handbook of Small Animal Gastroenterology, St. Louis, 2003, p. 211-250, Elsevier. Westermarck E: Tylosin-responsive diarrhea. In Bonagura JD and Twedt DC, eds: Current Veterinary Therapy XIV, St. Louis, 2009, p. 506-509, Elsevier.

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Drug Therapy for Vomiting in Dogs and Cats Todd R. Tams, DVM, DACVIM Chief Medical Officer VCA Pharmacologic Control of Acute Vomiting Initial nonspecific management of vomiting includes NPO (in minor cases a 4-12 hour period of nothing per os may be all that is required), fluid support, and antiemetics. Initial feeding includes small portions of a low fat, single source protein diet starting 6-12 hours after vomiting has ceased. Drugs used to control vomiting will be discussed here. The most effective antiemetics are those that act at both the vomiting center and the chemoreceptor trigger zone. Vomiting is a protective reflex and when it occurs only occasionally treatment is not generally required. However, patients that continue to vomit should be given antiemetics to help reduce fluid loss, pain and discomfort. For many years I strongly favored chlorpromazine (Thorazine), a phenothiazine drug, as the first choice for pharmacologic control of vomiting in most cases. The HT-3 receptor antagonists ondansetron (Zofran) and dolasetron (Anzemet) have also been effective antiemetic drugs for a variety of causes of vomiting. Metoclopramide (Reglan) is a reasonably good central antiemetic drug for dogs but not for cats. Maropitant (Cerenia) is a superior broad spectrum antiemetic drug and is now recognized as an excellent first choice for control of vomiting in dogs and cats. In addition to antiemetic effect, maropitant also provides visceral analgesic effect. Maropitant is also the first choice for prevention of motion sickness vomiting in both dogs and cats.

Metoclopramide (Reglan) is a gastric prokinetic drug that also has central antiemetic effect. Metoclopramide increases gastric and proximal small intestinal motility and emptying without causing acid secretion, decreases enterogastric reflux, and provides inhibition of the chemoreceptor trigger zone. The central antiemetic effect is mediated through antagonism of dopaminergic D2 receptors in the chemoreceptor trigger zone of the medulla to inhibit vomiting induced by drugs, toxins, metabolic disease, and acid-base imbalances. Metoclopramide is a less effective central antiemetic drug in cats than in dogs because serotonin receptors, rather than dopaminergic receptors, predominate in the CTZ of cats. For vomiting in cats, I generally usually use metoclopramide only if a prokinetic effect is desired. Chlorpromazine, dolasetron, ondansetron, or maropitant should be used as a first or second choice to control acute frequent vomiting in cats. Parvovirus can cause gastric hypomotility and therefore the promotility effects of metoclopramide may prove beneficial. However, maropitant, dolasetron, or ondansetron are more effective drugs than metoclopramide for managing vomiting caused by parvovirus. Further, maropitant also helps provide visceral analgesia and is the best single drug choice in parvo cases. The recommended injectable dose of metoclopramide is 0.2 to 0.5 mg/kg IM or SC given TID to QID as needed. Metoclopramide can also be given IV as a constant rate infusion (1 - 2 mg/kg over 24 hours). Metoclopramide should not be used if gastric outlet obstruction or GI perforation is suspected, or in patients with a seizure disorder. 117

Metoclopramide - Clinical Applications for Chronic Vomiting Several clinical applications for use of metoclopramide in dogs with chronic vomiting have been identified. These include gastric motility disorders, gastroesophageal reflux disease (GERD), primary or adjunctive therapy for antral and pyloric mucosal hypertrophy, and as treatment for nausea and vomiting caused by various other disorders. While cisapride is a superior prokinetic drug, metoclopramide is an effective drug and is often the first choice for prokinetic effect, with cisapride used as a second choice if metoclopramide is not effective. Other drugs that are sometimes used for prokinesis are low dose erythromycin and the H2receptor blocker ranitidine (Zantac). Gastric motility disorders have been recognized with increased frequency in veterinary medicine, but are still overlooked. Gastric stasis, characterized by abdominal discomfort, periodic bloating, borborhygmus, nausea and vomiting may be associated with a number of clinical states that include inflammatory disorders (e.g., chronic gastritis, IBD), gastric ulcers, gastroesophageal reflux, infiltrative lesions (e.g., neoplasia), and chronic gastric dilatation. Metabolic disturbances that may cause gastric stasis include hypokalemia, hypercalcemia, acidosis, anemia, and hepatic encephalopathy. Short-term continued vomiting that is observed in some cases after apparent recovery from viral enteritis may be due to abnormal gastric motility. Transient (3 to 14 days) gastric hypomotility may also occur after gastric or abdominal surgery. Motility disorders with no organic cause may be best classified as idiopathic. For any of the disorders listed, the primary cause should be treated, and metoclopramide may be a valuable short-term adjunct to therapy in these cases, along with feeding low fat foods in divided amounts. Metoclopramide alternatively may be used as the primary treatment on a long-term basis for idiopathic hypomotility disorders. Metoclopramide has also been useful in treatment of dogs that have chronic vomiting characterized by episodes occurring routinely in the early morning and containing bilious fluid. In general, patients less than 4.5 kg (10 lb) receive 2.5 mg per dose), 4.5 to 18 kg (11-40 lb) 5 mg per dose, and greater than 18 kg (40 lb) 10 mg per dose. Metoclopramide is given 30 to 45 minutes before meals and again at bedtime. Animals that require chronic medication may need only 1 to 2 doses daily. Because of its short half-life, the drug is not effective when given by intravenous or intramuscular bolus injection for purposes other than when only one treatment would be administered (i.e., to aid in evacuating the stomach if an anesthetic procedure in a non-fasted patient becomes necessary, pre-radiologic contrast study). Subcutaneous administration into fat may be of benefit when oral therapy is contraindicated and an intravenous line is not available. Metoclopramide is less effective as a promotility drug than cisapride (see later discussion). While many animals with gastric hypomotility respond well to metoclopramide, some have a less than desired response. If a patient with a suspected gastric hypomotility disorder has an inadequate response to metoclopramide, cisapride should be tried next. Side Effects Some adverse effects may occur if metoclopramide is given in the usual therapeutic doses. Clients should be apprised of these before the medication is prescribed. These effects are uncommon in animals, and somewhat more common in humans. Motor restlessness and hyperactivity may occur; and when observed, these signs usually begin 20 to 30 minutes after a dose and last 4 to 5 hours. The reaction can range from mild 118

to quite dramatic. Alternatively, drowsiness and depression occasionally occur. Side effects are infrequent in cats, but clients have reported disorientation, frenzied behavior, and hiding tendencies associated with the medication. Hospitalized animals may chew excessively at catheter sites or be more aggressive toward hospital staff. Sometimes these effects are subtle and nursing staff need to be observant. These side effects are reversible (diphenhydramine [Benadryl 2.2 mg/kg IV] or discontinuing the drug) but generally do not subside when lower doses are given. Unless side effects are infrequent, the use of metoclopramide should be discontinued if adverse reactions are seen. Cisapride does NOT cause these same type of adverse reactions. Metoclopramide crosses the blood brain barrier, cisapride does not. In general, metoclopramide should not be given to epileptic patients. Other contraindications include evidence of significant mechanical obstruction, simultaneous use of anticholinergic agents (antagonism of metoclopramideâ&#x20AC;&#x2122;s effects), and pheochromocytoma. Ondansetron - Clinical Applications for Acute Vomiting Ondansetron (Zofran) is a potent antiemetic drug that has proven to be effective in both humans and animals for control of severe vomiting. It has been used in human cancer patients undergoing cisplatin therapy, a drug that frequently causes nausea and severe vomiting, with very good results. Ondansetron acts as a selective antagonist of serotonin S3 receptors (a principal mediator of the emetic reflex). S3 receptors are found primarily in the CTZ, on vagal nerve terminals, and in the gut in enteric neurons. The principal site of action of ondansetron is in the area postrema, but it also has some peripheral gastric prokinetic activity. In my experience, ondansetron has produced very good results in either controlling or at least significantly decreasing the frequency of vomiting in dogs and cats with frequent or severe vomiting, including in dogs with severe parvovirus enteritis, in pancreatitis patients, and cats with hepatic lipidosis. The recommended dose is 0.5 to 1 mg/kg IV given as a slow push every 6 to 12 hours (based on patient response). Frequently dogs that appear quite distressed due to nausea and vomiting look much more relaxed and comfortable within 15 minutes of receiving ondansetron. There are no reports of any significant side effects such as diarrhea, sedation, or extrapyramidal signs in human and animal trials. While Zofran was quite expensive for many years, it came off patent in 2007 and is now more affordable for use at any small animal hospital. Currently, however, my top antiemetic drug of choice is maropitant (Cerenia), because it is a highly effective antiemetic drug but also because it provides visceral analgesic effects as well. Animals with significant liver disease may be best managed with ondansetron or dolasetron, as maropitant should be used with caution in animals with significant hepatic dysfunction (although it is not contraindicated â&#x20AC;&#x201C; some clinicians have used maropitant successfully and safely in animals with liver disease). Dolasetron Dolasetron (Anzemet) is also a 5-HT3 receptor antagonist antiemetic drug, with action similar to ondansetron. It is a slightly less expensive alternative to ondansetron and only needs to be administered once daily. Indications are the same as for ondansetron, namely, for control of frequent vomiting that is poorly responsive to lesser expensive front-line antiemetic drugs. The dose is 0.5-1 mg/kg IV once daily. Dolasetron is generally well tolerated in animals.

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A NEWER ANTIEMETIC DRUG FOR DOGS Most drugs used to control vomiting in animals have been developed for use in humans. There has been a need for a broad-spectrum antiemetic drug for use in animals that is effective in a variety of situations, has a rapid onset of action, is safe and affordable, and is available in both injectable and oral preparations. Maropitant citrate (Cerenia) is a newer broad-spectrum antiemetic drug that is indicated for the treatment of acute vomiting in dogs. Maropitant is a neurokinin receptor antagonist that blocks the pharmacologic action of the neuropeptide substance P in the central nervous system. Substance P is found in significant concentrations in the nuclei comprising the emetic center and is considered a key neurotransmitter involved in emesis. By inhibiting the binding of substance P within the emetic center, maropitant provides broad-spectrum effectiveness against both neural and humoral causes of vomiting. Clinical trials and recent clinical experience, since August 2007 when the drug was released for use in the U.S., have shown maropitant to be very effective for control of a variety of causes of acute vomiting in dogs. It is administered as a once-daily injection (0.45 mg/lb [1 mg/kg] SC for dogs), which is a significant advantage over many other antiemetic drugs, and has a rapid onset of action. Maropitant is also available in tablet form for outpatient use, which makes it a very attractive choice for use in small animal practice. It is the drug of choice for dogs with motion sickness. CAUTION: We generally advise that Cerenia be used at a reduced dose (50%) for animals with significant hepatic dysfunction, OR select an alternative antiemetic for animals with liver disease â&#x20AC;&#x201C; e.g., ondansetron or dolasetron. The issue of stinging on injection: Information from clinical experience and studies indicates that there is less likelihood for stinging to occur with maropitant injections when the product is kept refrigerated. The current guidance is that the solution should be kept refrigerated and drawn up and injected right away at refrigerated temp. In practice a sting can still be expected in some patients even when the product is kept refrigerated. CATS: Studies have now been done using maropitant in cats and some clinicians in general practice have been using it since 2008. In May 2012 Cerenia was approved for use in cats and also in puppies as young as 8 weeks of age. Recommended dose of maropitant for cats: Injectable: 0.5-1 mg/kg SC or IV (give SLOWLY over 60-90 seconds if administering IV) Oral: (1 to 2 mg/kg). This is the starting dose recommended for prevention of motion sickness in cats as well; i.e., somewhat lower than the canine dose for motion sickness. Note: On January 14, 2016, Zoetis announced a new label claim for IV use of Cerenia. In two separate bioequivalence studies conducted in 2015 by Zoetis in dogs and cats, when delivered intravenously, CERENIA reached concentration and absorption levels as quickly as with subcutaneous injection. Additionally, two separate safety studies in dogs and cats indicated no related effects on survival or clinical findings, and there were no reports of pain on intravenous injection.

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Consider Using Cerenia More Routinely Administered PRE-Operatively Some practices have now instituted the practice of including an injection of Cerenia administered routinely in the pre-operative period. I am a strong proponent. Reasons for doing this include: - Help prevent post-op vomiting and nausea and decrease chances of aspiration - Adjunctive visceral analgesia - Improved patient comfort in the post-op period - Earlier return to eating, with improved appetite and volume of food consumption In this setting, Cerenia can be administered anytime in the pre-op period. If morphine or hydromorphone are going to be given as part of the pre-anesthesia sedation and preemptive analgesia plan, and the clinician desires to prevent vomiting secondary to these emetogenic drugs, Cerenia is administered 45 minutes prior to the emetogenic drugs. In one study when Cerenia was administered 45 minutes prior to morphine at 0.5 mg/kg, 0/15 dogs vomited, while 15/16 dogs who received saline instead of Cerenia vomited at least once (and 4 of the dogs vomited 4 times). We have seen excellent post anesthesia recovery periods in dogs that have undergone a variety of procedures, including OVH/neuter as well as prolonged anesthesia for dental procedures, major abdominal procedures, etc. We are also using Cerenia more routinely prior to performing endoscopic procedures. The uniform response is that most patients recover more smoothly, more quietly and are presumably more comfortable overall. Clients of course are very happy when their pet eats earlier than would be otherwise expected. This has represented a gratifying advance in patient care in many ways - - helping our patients be more comfortable is always good.

How long can Cerenia be used on a consecutive days schedule? The original label guidance stated that Cerenia should not be given for more than 5 consecutive days (injectable or oral at the anti-emesis dose) and for 2 days at the motion sickness prevention dose. However, experience has shown that in some patients Cerenia has been used safely and effectively on a longer term basis (anecdotal reports, e.g., patients with neoplasia or renal disease that were experiencing ongoing nausea, vomiting, and inappetence). Many of these patients have a much better quality of life while on Cerenia, as they have less nausea and vomiting and a much better appetite. There are cats that have been treated with a daily oral dose for months to several years. Use of Cerenia in this fashion is being investigated further. Further, in 2015 the label was changed, based on studies that evaluated the effect of maropitant when given at various doses for longer periods of time. Cerenia has a high safety profile and a longer duration of use, based on each patientâ&#x20AC;&#x2122;s individual needs, is now well accepted. A study was presented at the Veterinary Cancer Society (VCS) meeting in San Diego Oct. 29-November 1, 2010, and then subsequently at the ACVIM Forum in Denver in June 2011: Pharmacokinetics of maropitant citrate dosed orally to dogs at 2 mg/kg and 8 mg/kg once daily for 14 consecutive days. Two groups of eight healthy beagle dogs were administered maropitant citrate at 2 or 8 mg/kg orally once daily for 14 days. Concentrations of maropitant and its metabolite were measured in plasma using a LC-MS/MS assay. 121

Pharmacokinetic parameters were estimated using non-compartmental pharmacokinetic techniques and a modeling approach was used to estimate steady-state. Results: The model estimate for the number of doses required to reach 90% of steady-state was 4.30 for 2 mg/kg and 8.09 for 8 mg/kg. Four dogs experienced a single dose of vomiting. Conclusions: Dosing maropitant citrate beyond the original label duration of 5 days was well tolerated by healthy dogs. During the 14 days of dosing there was accumulation, however, steady-state was reached after approximately 4 doses for daily 2 mg/kg dosing and 8 doses for daily 8 mg/kg oral dosing. Use of Oral Maropitant (Cerenia)  Confident there is no GI foreign body (i.e., do not use ongoing antiemetic therapy if there could be a foreign body ledged in the GI tract)  Prevent vomiting during cyclosporine, azithromycin, or other drug induction period (use for 3-5 days in conjunction with the start of a drug that might cause vomiting)  Vomiting flare-ups in IBD patients (or other chronic disorders)  Pancreatitis, parvovirus, etc for a few days after vomiting is fairly well controlled with injectable maropitant. Excellent control of nausea may help improve appetite and earlier food intake  Prevention of vomiting in chemotherapy patients  Prevention of motion (“car”) sickness  Renal disease patients – and perhaps chronic use (these patients may benefit tremendously and we have observed many patients that eat better, do not vomit or exhibit nausea, and feel better overall. Studies are ongoing).

Cisapride Cisapride is a potent GI prokinetic drug and is superior in action to metoclopramide. It is no longer on the market for use in humans, as of 2000, because of an association with fatal arrhythmias. There are no reports of similar complications existing in dogs and cats, however, and cisapride continues to be readily available to veterinarians through compounding pharmacies. Cisapride has broader promotility effects than metoclopramide (e.g., cisapride has demonstrated excellent efficacy in management of colonic inertia and small intestinal ileus). In contrast to metoclopramide, which has central effect at the CRTZ in addition to its peripheral effects, cisapride has no known direct antiemetic properties. Another contrast is that metoclopramide’s prokinetic effect is most significantly on the stomach. It is NOT a reasonable choice for treatment of small intestinal ileus.

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The most relevant uses of cisapride in animal patients include treatment of gastroparesis, especially in patients that experience significant side effects from metoclopramide (e.g., hyperactivity and other dystonic reactions) or where metoclopramide is not sufficiently effective, idiopathic constipation, gastroesophageal reflux disease (if H2-receptor antagonists or proton pump inhibitors and dietary management alone are not effective), and postoperative ileus. . Cisapride is extremely well tolerated by animal patients. I have used cisapride in dogs and cats that have experienced neurologic side effects from metoclopramide. I have observed no adverse reactions to cisapride in any of these patients, even in those whose side effects to metoclopramide included very bizarre behavior changes. The suggested dose of cisapride is similar to what has been recommended for metoclopramide (see earlier discussion).

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Companion Animal

Leah Cohn, DVM, PhD, DACVIM (SAIM)

Professor of Veterinary Medicine â&#x20AC;¢ Director of Graduate Studies University of Missouri - College of Veterinary Medicine Columbia, Mo.

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Leptospirosis Leah A. Cohn, DVM, PhD, DACVIM (SAIM) Professor, University of Missouri Leptospirosis is a disease with worldwide significance which affects many different species, including both dogs and people (cats rarely, if ever, develop clinical disease). Several antigenically distinct serovars of the same organism, Leptospira interrogans sensu lato and Leptospira kirschneri , are responsible for disease in dogs. Subclinically infected reservoir hosts serve as source of infection and maintain the organism in nature. Incidental hosts develop clinical illness, but shed organisms for shorter periods than do reservoir hosts. Preferences for reservoir host and likely incidental host vary with the serovar as well as with the geographic location. The serovars most commonly incriminated in canine infection, and their common reservoirs, include canicola (dog), icterohaemorrhagiae (rodents), grippotyphosa (raccoon, skunk, opossum, vole), pomona (cattle, swine, skunks, opossum), and bratislava (rodents, swine). Infection may follow either direct or indirect contact with the leptospire. The organisms is shed intermittently in the urine of an infected host for many months. Exposure of susceptible dogs to urine-contaminated water, soil, bedding, or food may allow the spirochete to penetrate mucus membranes or abraded skin. Once the organism gains entry, it can replicate in any of several tissues. The dog may clear the infection, maintain the organism (primarily in the kidney) without illness for prolonged periods, or develop clinical illness. Both virulence of the organism and host susceptibility influence the outcome of infection. Various serovars have a propensity to produce clinical disease with particular characteristics; renal, hepatic, and vasculitic disease are of most importance. Often, serovars canicola and grippotyphosa are described in association with renal dysfunction and minimal hepatic disease, while icterohaemorrhagiae and pomona produced both hepatic and renal damage. Realistically, the clinical disease is similar enough that the serovar resulting in infection can not be distinguished without confirmatory testing. Any serovar is capable of producing endothelial damage, vasculitis, and acute complications including disseminated intravascular coagulation and edema. Both large and small breed dogs are susceptible to infection. Most dogs develop only subclinical infection; serologic evidence of exposure exists, but no illness requires veterinary intervention. Dogs that do develop clinical illness may display peracute, acute, subacute, or chronic infection. Luckily, peracute infection is rare. In this form of the disease, death occurs within hours of massive leptospiremia, and may occur before owners have been able to note

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any ante mortem signs. When signs of acute infection are observed, they often include vomiting +/- hematemesis, shivering (due to fever), muscle tenderness, melena or hematochezia, petechiation, dehydration, and vascular collapse. Subacute infections are recognized far more commonly than peracute or acute disease. These dogs also present with a febrile illness, muscle tenderness, and vomiting. The vast majority display uremic symptoms and evidence of acute kidney injury (AKI, either polyuric or oliguric). A lesser proportion of infected dogs present with icterus and evidence of cholestasis. Respiratory manifestations include interstitial or hemorrhagic pneumonia with cough and sometimes dyspnea, but these manifestations are less common than renal symptomatology; interestingly, respiratory manifestations are more common in Europe. Coagulopathy may accompany subacute disease, but fulminant DIC is much less common than in the acute presentation. Ocular manifestations, including uveitis, are also a concern. Dogs that survive the subacute illness may develop chronic renal and/or hepatic disease manifestations. Interstitial nephritis and fibrosis may leave the animal with a state of chronic renal failure (ie, chronic kidney disease), while chronic active hepatitis may eventually lead to hepatic failure. Diagnosis is based on a combination of suggestive historical, physical, and laboratory findings, as well as confirmatory testing. As mentioned, a large majority of dogs with leptospirosis develop azotemia due to acute kidney injury. Hyperphosphatemia, metabolic acidosis, and isosthenuria are to be expected. Vasculitis leads not only to thrombocytopenia, but also to loss of albumin (and accompanying decreases in total serum calcium). An inflammatory leukogram is expected, although leukopenia may be seen in the earliest stages of disease. The presence of hyperkalemia is dependent upon the animalâ&#x20AC;&#x2122;s urine output; dogs with oliguric or anuric acute renal failure often demonstrate hyperkalemia, while polyuria is more likely to lead to hypokalemia. Animals with GI fluid loss often demonstrate some degree of hyponatremia, hypochloremia, +/- hypokalemia. Anywhere from 15 to 50 % of dogs with suacute leptospirosis develops hyperbilirubinemia and bilirubinuria. A bit more than a quarter of infected dogs display elevations in serum alanine transaminase (ALT), while about half display elevations in serum alkaline phosphatase (ALP). Aside from isosthenuria, the remainder of the urinalysis may indicate tubular damage via observation of proteinuria, glucosuria, and/or casts. Confirmatory testing includes indirect testing for the antibody produced in response to leptospirosis, or direct detection of leptospires. Direct testing methods include PCR identification of DNA from the leptospire, or less commonly, urine or blood culture, FA testing of urine, or urine dark-field microscopy. Antibiotic treatment quickly decreases the number of

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organisms in urine and blood, rendering any of these direct tests very poorly sensitive. Prior to use of antibiotics, PCR testing of urine is preferred for direct testing. Because leptospires are not shed continuously, any of these methods could yield a false negative result. Indirect testing uses serology to confirm antibody response rather than organism. Historically, a microscopic agglutination technique (MAT) was used most often to assay for antibody to a number of serovars. The presence of antibody represents past exposure rather than active infection, so vaccination will result in a positive antibody titer. A useful rule of thumb when interpreting titers in a vaccinated dog is that vaccination titers tend to be lower than disease titers. In fact, it is rare for vaccine-induced titers to exceed 1:400 at most labs after the first few month past vaccination. Because titers detect antibody (Ab), titer results may be negative or weakly positive early in the course of infection before a robust antibody response has had time to develop. In the face of acute illness, convalescent titers may be required to confirm disease. In recent years, point-of-care (POC) tests have become commonplace. Different POC antibody tests have different characteristics. The most commonly used are the IDEXX SNAP and the Zoetis Witness tests. The SNAP test detects Ab against outer membrane protein Lip32by ELISA (sensitivity 82%, specificity 96% per manufacturer), while the Witness test uses whole cell antigen extracts to detect IgM (sensitivity 98%, specificity 93.5% per manufacturer). Both tests may be negative early in infection (Witness may be positive first, by a short time), although either may become positive sooner than a MAT test. It seems vaccination is more likely to cause a positive test for a longer time to the SNAP test than the Witness test. Seroconversion or 4-fold increase in titer can confirm diagnosis if initial result is negative or if vaccination might be interfering in diagnosis. NOTE: vaccinated dogs are less likely to become ill from leptospirosis, so the importance of vaccine titers interfering in diagnosis is likely not key. Any dog with unexplained AKI should be treated as if it has leptospirosis. This includes not only appropriate therapy, but also handling precautions designed to protect exposed people and dogs. With early therapy, prognosis for recovery is fair to good, although chronic kidney disease (CKD) may be a sequelae in some dogs. In addition to routine measures implemented in the treatment of any dog with AKI (diuresis, antiemetics, proton pump inhibitors, etc), early antimicrobial therapy is important in the treatment of suspected leptospirosis. Antimicrobials decrease fever and diminish leptospiremia within hours of administration. Parenteral preparations are often required initially because vomiting precludes oral therapy. Penicillin derivatives are extremely effective at halting leptospiremia, but do not eliminate the carrier state. Doxycycline antibiotics may be used to halt leptospiremia and to treat carriers and are the antimicrobial of choice. Although duration of treatment necessary is not well documented, 5

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mg/kg doxycycline PO or IV q 12 h for 2 weeks is the current recommendation. Some dogs with AKI will require dialysis; this is true of essentially all dogs with oliguric AKI. Early referral is beneficial to a hemodialysis center (eg, The Ohio State University). Contaminated urine is highly infectious, and thus precautions must be used when handling dogs suspected of having this zoonotic disease. Latex gloves should be worn when handling urine or urine contaminated materials (including not only bedding, but the dogâ&#x20AC;&#x2122;s fur as well). Disposable gowns are ideal for handling these dogs as the fur may be contaminated with urine. Anyone handling these dogs should wash their hands completely afterwards. Surfaces that contact infected urine should be disinfected and dried thoroughly. Dogs should not be allowed to urinate in areas accessed by other dogs, and consideration should be given to urine containment via an indwelling urinary catheter (this also facilitates the ability to monitor for the development of oliguria). Collected urine (and all wastes) should be handled as a biohazard, though urine can be disinfected with bleach before disposal through the drains. Contaminated runs should not be pressure washed, and protective eyewear/face mask should be used during clean up of contaminated runs. Although we do not know for certain how long shedding lasts after treatment, full precautions should continue for at least 3 days after starting antimicrobial drugs. Pet owner or others in contact with the patient should notify their physician if they are pregnant or immune suppressed, or if illness develops. Often, state veterinarians will ask to be notified of confirmed infection. Vaccines do not deliver cross protection between serovars. For over two decades, vaccinations were designed to impart resistance to infection with serovars canicola and icterohaemorrhagiae but did not provide protection from other serovars. In recent years, documented infection with these two serovars has been quite rare, but infection with serovars grippotyphosa, pomona, and bratislava have increased in frequency. For this reason, pharmaceutical manufacturers have developed newer vaccines designed to protect against infection with grippotyphosa and pomona. For now, the USDA has not licensed any vaccine containing the serovar bratislava. As with most bacterial vaccines, immunity is not as long lasting as immunity to viral antigens. Yearly boosters are recommended for at risk. Although lepsospiral vaccines have historically been incriminated in more adverse vaccine reactions than other commonly used vaccines, newer, â&#x20AC;&#x153;cleanerâ&#x20AC;? subunit vaccines have led to a reduction in the number of these adverse reactions. Suggested readings

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Curtis, K. M., et al. "Performance of a Recombinant LipL32 Based Rapid In-clinic ELISA (SNAP® Lepto) for the Detection of Antibodies Against Leptospira in Dogs." International Journal of Applied Research in Veterinary Medicine 13.3 (2015). Juvet, F., et al. "Urinary shedding of spirochaetes in a dog with acute leptospirosis despite treatment." Veterinary Record-English Edition 168.21 (2011): 564. Lizer, J., et al. "Evaluation of 3 Serological Tests for Early Detection Of Leptospira‐specific Antibodies in Experimentally Infected Dogs." Journal of veterinary internal medicine 32.1 (2018): 201-207. Schuller S., Francey T, Hartmann K, et al. European consensus statement on leptospirosis in dogs and cats. Journal of Small Animal Practice (2015) 56, 159–179 . Sykes, J. E., et al. "2010 ACVIM small animal consensus statement on leptospirosis: diagnosis, epidemiology, treatment, and prevention." Journal of Veterinary Internal Medicine 25.1 (2011): 1-13. Troìa, R., et al. "Prospective evaluation of rapid point-of-care tests for the diagnosis of acute leptospirosis in dogs." The Veterinary Journal 237 (2018): 37-42.

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Feline Infectious Peritonitis Leah A. Cohn, DVM, PhD, DACVIM (SAIM) Professor, University of Missouri Feline infectious peritonitis (FIP) is a typically fatal disease of cats often characterized by body cavity effusions, icterus, neurologic signs, or uveitis. It is caused by a common feline coronavirus (FCoV) that in clinically affected cats has spontaneously mutated from a benign, minimally pathogenic virus to an aggressive, lethal virus. FCoV is spread via a fecal-oral route, and is ubiquitous in the environment. Cat-to-cat transmission of the mutated FIP virus does not occur under natural circumstances; instead, cats contract ordinary FCoV and it will either mutate inside the cat to cause FIP, or it will not. Cats can either stop shedding FCoV or may be persistent shedders. FIP can occur in all Felidae family members. Young cats during post-weaning periods are most susceptible (peak age, 3 months to 2 years), but cats of all ages can be affected. It is more common in purebred cats, likely at least in part because they often come from multi-cat environments. Genetic predisposition is suspected but specific genetic susceptibility is not known. Risk factors include young (or old) age, multi-cat environments (catteries, shelters, pethoarding environments), stressful situations, and immunosuppression. Historically, there have been two clinical forms of FIP: dry form (non-effusive) and wet form (effusive). The most important difference in the forms is that the wet form is much easier to recognize than is the dry form. As a general rule, however, the wet form occurs at a somewhat younger age and progresses more rapidly than the dry form. Every cat with body cavity effusion also has microgranulomas, and cats with the dry form will commonly develop effusion later. Therefore, the differentiation is really one describing clinical presentation and not a difference in pathogenicity. Signs of FIP are often vague, and typically include lethargy, hyporexia, and weight loss. Abdominal distention due to abdominal effusion or respiratory distress due to pleural effusion are common, especially in younger kittens. Gastrointestinal (GI) signs are common, and neurologic signs from central nervous system (CNS) involvement also occur. Physical examination often reveals fever, abdominal fluid wave, and/or tachypnea and muffled lung and heart sounds due to pleural effusion. Uveitis, icterus, or CNS deficits (ataxia, altered mentation, nystagmus, etc) are sometimes identified, as may be lymphadenopathy, organomegaly, or irregular kidneys. There are classic findings suggestive of FIP on routine laboratory testing. These include lymphopenia, neutrophilia without left shift (stress leukogram), mild nonregenerative anemia of chronic inflammation, and increased total protein/total solids on CBS. Serum biochemistry

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profile often demonstrates hyperglobulinemia (and low albumin/globulin ratio) and increased bilirubin. Serum protein electrophoresis is not usually performed, but should demonstrate a polyclonal gammopathy. Fluid analysis from effusion is usually straw-colored and viscous, with high protein (often > 3.5 mg/dL) but low cell counts. The fluid is not septic. A simple and yet useful test is the Rivalta test. Simply add 1 drop effusion to water-acetic acid mixture, watching for coagulation (lava lamp look); sensitivity 91%, specificity 65%. If the Rivalta test is negative, wet FIP is extremely unlikely. Cerebrospinal fluid (CSF) analysis can be unremarkable or may demonstrate cytoalbuminologic disassociation (ie, high protein with low cell count). In addition to lab testing, imaging studies can also be suggestive, be that by identifying fluid accumulations or granulomas in parenchymal tissues. The only way to definitively confirm a diagnosis of FIP is via immunohistochemical demonstration of FCoV antigen in macrophages, but this requires tissue biopsy or necropsy. An alternative method is detection of FCoV antigen in macrophages collected from CSF, tissue aspirates, or aqueous humor (but not blood) by immunofluorescence or immunocytology staining; this can result in false positives but has a rather high specificity (72%) and sensitivity (85%). There exist several PCR tests for FIP, some of which are better than others but none are perfect. PCR to detect specific mutations in the spike protein that leads to FIP-inducing FCoV reportedly has a very good specificity (96%) and fair sensitivity (69%) for effusion but it is not useful for blood. Routine PCR for FCoV is not useful. Serum antibody tests for FCoV have very little use as they only demonstrate exposure to a coronavirus (including FIP vaccine virus), not FIP, and most corona antibody titer positive cats will never develop FIP. Additionally, the text canâ&#x20AC;&#x2122;t be used to rule out FIP as about 10% of infected cats do not develop antibodies or stop making antibodies when they are ill from FIP. Realistically, a kitten from a multicat environment with typical history, exam, and routine lab tests can be comfortably diagnosed as having FIP. Cats without effusion or that donâ&#x20AC;&#x2122;t fit the norms of age, exposure, etc, are more problematic. Differentials should be ruled out as best as possible (eg, toxoplasma testing as a differential for CNS deficits) with consideration of biopsy or antibody testing. To date, FIP is considered incurable and fatal with rare exceptions of spontaneous recovery. The treatment goal is to provide comfort and some additional time. For cats with effusion, centesis may improve clinical signs, and especially improve respiratory compromise. Traditional therapy is immunosuppression, usually with glucocorticoids. Prednisolone 2 mg/kg PO q 24h, which may be reduced if the cat is stable for a few months, plus or minus cavitary injections of dexamethasone are typical. Immunomodulating drugs have been used with little efficacy. Feline interferon-omega showed no efficacy in a placebo controlled trial. In a case

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report, human interferon-alpha 30 U/CAT PO q 24h on alternating weeks was used with no obvious ill effects, but there are no proven benefits. Polyprenyl immunostimulant was able to prolong life of a few cats with FIP without effusion in a case series but controlled studies are missing. Readily available antiviral drugs show no benefit and several (eg, ribavirin) cause severe adverse effects. Supportive care is important, such as provision of adequate nutrition, antibiotics for secondary infections, or treatment of uveitis. Recently, there is more reason to hold out hope for recovery. A new antiviral drug now called GC376 has resulted in some apparent cure for cats with FIP (Pedersen 2018). This is a 3C-line protease inhibitor antiviral drug that resulted in improvement in 19/20 naturally infected cats. Of these, 5 kittens with wet FIP were in remission for anywhere from 5 to 14 months, with at least one cat apparently cured two years after starting treatment. This drug is not yet FDA approved, but the approval process has begun. The same authors also published in vitro and in vivo efficacy studies of a nucleoside analog GS-441524 small molecule viral inhibitor. In 10/10 kittens experimentally infected, treatment result in apparent cure. Prevention of FIP would be ideal. Unfortunately, the vaccine, while safe, appears to have limited efficacy. Strict hygiene and reduction of stress can be helpful. Theoretically, removing continuous or high FCoV shedders would helpful but it is difficult to identify such cats. If catteries have only FCoV antibody titer negative healthy cats, it demonstrates that they have likely not been exposed to FCoV, which in turn would make the risk of FIP extremely small. There is no need to handle cats sick with FIP as if they are contagious to other cats.

Suggested Readings Addie D, et al: Feline infectious peritonitis. ABCD guidelines on prevention and management. J Feline Med Surg 11:594-604, 2009. Doenges SJ, et al: Comparison of real-time reverse transcriptase polymerase chain reaction of peripheral blood mononuclear cells, serum and cell-free body cavity effusion for the diagnosis of feline infectious peritonitis. J Feline Med Surg 19:344-350, 2017. Doenges SJ, et al: Detection of feline coronavirus in cerebrospinal fluid for diagnosis of feline infectious peritonitis in cats with and without neurological signs. J Feline Med Surg 18:104109, 2016. Felten S, et al: Detection of feline coronavirus spike gene mutations as a tool to diagnose feline infectious peritonitis. J Feline Med Surg 19:321-335, 2017. Felten S, et al: Investigation into the utility of an immunocytochemical assay in body cavity effusions for diagnosis of feline infectious peritonitis. J Feline Med Surg 19:410-418, 2017.

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Felten S, et al: Utility of an immunocytochemical assay using aqueous humor in the diagnosis of feline infectious peritonitis. Vet Ophthalmol 21:27-34, 2018. Fischer Y, et al: Randomized, placebo controlled study of the effect of propentofylline on survival time and quality of life of cats with feline infectious peritonitis. J Vet Intern Med 25:1270-1276, 2011. Gruendl S, et al: Diagnostic utility of cerebrospinal fluid immunocytochemistry for diagnosis of feline infectious peritonitis manifesting in the central nervous system. J Feline Med Surg 19:576-585, 2017. Hartmann K, et al: Treatment of cats with feline infectious peritonitis. Vet Immunol Immunopathol 123:172-175, 2008. Hartmann K: Feline infectious peritonitis. Vet Clin North Am Small Anim Pract 35:39-79, 2005. Licitra BN, et al: Mutation in spike protein cleavage site and pathogenesis of feline coronavirus. Emerg Infect Dis 19:1066-1073, 2013. Murphy BG, et al. The nucleoside analog GS-441524 strongly inhibits feline infectious peritonitis (FIP) virus in tissue culture and experimental cat infection studies. Vet Micro 219:226-233, 2018. Pedersen, Niels C., et al. Efficacy of a 3C-like protease inhibitor in treating various forms of acquired feline infectious peritonitis. J Feline Med Surg 20: 378-392, 2018. Ritz SJ, et al: Influence of feline Interferon-omega on the survival time and quality of life of cats with feline infectious peritonitis. J Vet Intern Med 21:1193-1197, 2007. Scherk MA, et al: 2013 AAFP Feline Vaccination Advisory Panel report. J Feline Med Surg 15:785-808, 2013.

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Tick Transmitted Infections (Parts 1 and 2) Leah A. Cohn, DVM, PhD, DACVIM (SAIM) Professor, University of Missouri INTRODUCTION Blood-sucking arthropods are common causes of disease in pets (table 1), both by directly (eg, itching, anemia) and indirectly (eg, pathogen transmission). Mosquitoes, flies, fleas, and ticks are each capable of transmitting a variety of microbes including parasitic worms, protozoa, viruses, and bacteria. Of course, not all vector transmitted microbes are potential pathogens, and not all potential pathogens cause disease. Many microbes are well-adapted to a reservoir host and only rarely cause disease in the reservoir species (eg, Bartonella henselae seems to rarely cause obvious/overt disease in cats). Disease may be more likely when the potential pathogen infects a non-reservoir host (eg, Cytauxzoon felis causes death in the vast majority of infected domestic cats but often only a mild, short lived illness in the reservoir bobcat). The mechanism of pathogen transmission varies depending on the pathogenic organism and vector. Ticks feed for extended periods of time in a single site. During the long period of feeding, they not only “suck” blood from the host, but they also “spit” into the host. The salivary fluid inoculated during tick feeding includes anticoagulants, analgesics and antipruritics, immunomodulatory molecules, and pathogens. Many pathogens must be “activated” to move from the tick’s mid-gut to the salivary gland prior to inoculation. Although this movement may take some time, it is unwise to assume that there is always a risk-free period to mechanically remove ticks prior to pathogen transmission. WHEN AND WHERE ARE DISEASES IDENTIFIED? For the most part, vector transmitted pathogens occur where the vectors are found. For some diseases, alternative means of transmission allow disease to occur even where the vector is not found. As an example, the Haemaphysalis vector tick for Babesia gibsoni is not found in the USA but we do recognize disease caused by this pathogen. Perinatal transmission is an alternative means of disease transmission, so that affected dams pass on the pathogen to their pups. This helps explain why pit bull dogs are over-represented in the USA – infected pit bulls were imported from Asia, and pit bull dams give birth to pit bull pups! Information on vectors and disease in a given geographic region can be found in several locations. Centers for Disease Control maps are very useful in demonstrating the geographic range of vectors such as the various tick species. Veterinary resources including the website capcvet.org are also very useful for this purpose. Some tick species are found throughout the USA but others demonstrate a more restrictive geography. This explains why diseases like

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cytauxzoonosis are found in some geographic regions and not others, and why as the region for the tick expands, the region that disease if found expands too. Each tick species has a unique ecology; different geography and climate, feeds on different host species during different phases of the life-cycle, has seasonal feeding behavior, etc. These differences help explain not only where diseases occur, but when. For instance, the acute vasculitis caused by Rocky Mountain Spotted Fever is seen especially often in the late spring due to the feeding behavior of the largely outdoor American Dog tick, while Brown Dog ticks often lives inside buildings such as kennels or sheds year round, and thus, like fleas, can transmit infections any time of year. Table 1: Vectors and Diseases They Transmit Lone Star ticks Brown dog American Dog ticks ticks Granulocytic ehrlichiosis

Canine monocytic ehrlichiosis Cyclic thrombocytopen ia Rocky Mountain spotted fever

Q fever

Tularemia Cytauxzoonosis

Babesiosis

Panola Mountain ehrlichiosis Human monocytic ehrlichiosis

Hepatozoonosis (H. canis) Tularemia

Black legged ticks

Soft bodied ticks

Rocky Mountain spotted fever

Lyme disease

Tick borne relapsing fever

Bartonellosis

Granulocytic anaplasmosis

Tularemia

Fleas Biting insects

Hemotropic Mycoplasma

Gulf coast ticks

Chagas disease

Bartonellosis

Hepatozoonosis (H. americanum)

Leishmaniosis

Plague

Tick transmitted infections of importance in Missouri Although there are occasional diagnosis of many tick transmitted diseases in Missouri, the most important include Ehrlichiosis (predominantly dogs), Rocky mountain spotted fever (dogs), cytauxzoonosis (cats), and tularemia (predominantly cats). Though not yet common in the state, more cases of Lyme disease (dogs) are recognized here now than in the past. Each of these infections will be discussed in some detail. Salient features are presented below in table form;

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Pathogen Disease

E. ewingii Granulocytic ehrlichiosis

Subclinical infection

Very common

R. rickettsia Rocky mountain spotted fever

C. felis Cytauxzoonosis

Recovered carriers possible

F. tularensis Tularemia

B. burgdorferi Lyme

Very common

Dz manifestation Primary diagnostic test Prognosis

Treatment

Polyarthritis, neurologic signs Serology

Acute vasculitis

Febrile systemic illness Serology

Polyarthritis or glomerulonephritis

Serology

Acute, rapidly fatal organ failure Blood smear

Excellent

Guarded

Poor

Guarded

Doxy or minocycline

Atovaquone and azithromycin

Pradofloxacin

Excellent (arthritis) to poor (nephritis) Doxy or minocycline

Serology (C6 peptide)

RECOGNIZING INFECTION AND DISEASE Infection and disease are two entirely different things. As previously mentioned, animals can become infected with potential pathogens and yet remain well. Therefore, even when testing identifies that an animal has been infected with a pathogen it does not prove disease causation. A serologic response to prior infection can remain even after the inciting organism has been cleared from the body, the serologic response and even the organism may persist when illness does not exist, or serologic cross reactivity between related organism may lead to a positive test for a pathogen when no infection ever occurred. For example, a positive antibody test for Rickettsia may be positive as a result of infection with Rickettsia rickettsia, the cause of Rocky Mountain Spotted Fever, but it also might be positive due to infection with an entirely different and non-pathogenic spotted fever group Rickettsia spp. A positive serologic or PCR based test in the presence of classic disease signs can provide strong supportive evidence of disease due to infection, but these tests are often used in healthy animals as screening tests. Screening tests offer both pro’s and con’s (table 2), and the decision on when to use these tests will depend on a variety of factors. Perhaps the single most important “pro” to use of screening tests is that it can inform ectoparasite control. When a screening test is positive for any pathogen, it creates a much more compelling argument for owners to regularly use ectoparasite control products if they know that their pet has not only been bitten by an arthropod vector, but that the vector transmitted a potential pathogen. Table 2: Pro’s and Con’s of Screening Healthy Pets for Vector Borne Diseases Pro’s Con’s May allow treatment that prevents disease False +’s in low prevalence areas Provides regional prevalence information May lead to unnecessary treatment Provides sentinel information May identify resolved (past) infection May reduce pathogen reservoir May identify infection that would never cause disease

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Alerts to non-tested pathogens carried by the same vector Informs ectoparasite control

Treatment may not eliminate pathogen Treatment won’t prevent re-infection

How should a positive screening test in a healthy animal be handled? The answer depends on a number of factors, including likelihood of true infection. For example, if a positive Lyme test is found in a dog that has never been to an endemic region, the test results is unlikely to be of import. Or, a positive test for Ehrlichia in a dog living in the mid-west is more likely due to the less pathogenic E. ewingii (or even E. chaffensis) than to the more pathogenic E. canis. While there is no single answer to what to do when screening tests are positive, there are some guidelines for additional testing warranted by a positive result for the most commonly screened pathogens (Table 3). For those healthy dogs with no clinical or laboratory evidence of true infection, it is reasonable to forgo antimicrobial treatment. However, continued vigilance is required including discussion of clinical disease with pet owners and yearly repetition of the additional screening test (eg, repeat CBC/UA yearly). Repetition of the actual vector-borne disease screen is likely not necessary as these serologic tests may remain positive, or be intermittently positive, for months to years. Table 3: Suggested Additional Measures for Healthy Dogs with Positive Screening Tests Ehrlichia Lyme Anaplasma Test for thrombocytopenia Test for thrombocytopenia Test for thrombocytopenia Blood smear (or buffy coat) Test for proteinuria Blood smear evaluation for evaluation for morulae morulae • Granulocyte – E. • Granulocyte – A. ewingii phagocytophilum • Monocyte – E. canis • Platelet – A. platys Test for anemia Consider quantitative C6 Test for proteinuria peptide measurement (≥30 U/mL support treatment) Test for proteinuria Test for hyperglobulinemia Discuss vaccination against Lyme RE-EVALUATE RE-EVALUATE RE-EVALUATE ECTOPARASITE CONTROL ECTOPARASITE CONTROL ECTOPARASITE CONTROL

Of course, false negative tests are just as possible as false positive tests. For acute infection, antibody based serologic tests may be negative simple because antibodies have not yet had time to form. This is the reason that convalescent testing can be crucial. For example, Rocky Mountain Spotted Fever is an acute vasculitis, and the initial antibody test is often negative. But if the test is repeated 2 to 3 weeks later, the convalescent titer will either demonstrate seroconversion (from negative to positive), or a four-fold increase in titer (eg, from an initial titer of 1:80 to a titer of 1:320). Although the use of antimicrobials may blunt the

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convalescent response slightly, it should not abrogate the response altogether. A common misconception is that sensitive PCR tests can be used to rule out infection; nothing could be further from the truth. While PCR tests are sensitive at detecting pathogen when it is present in a given sample, they can NEVER BE USED TO RULE OUT infection, but only to confirm the presence of pathogen nucleic acids. The pathogen may be in a tissue other than that tested; for example, Borrelia burgdorferi (the cause of Lyme disease) is found in connective tissues, not in blood, so a PCR test on blood is unlikely to be positive even during active infection. Other pathogens may be present in the blood, then absent, and sometimes then present again in blood; such is the case for Ehrlichia canis. In general, PCR is more likely to be found in blood early in the course of infection rather than later. An additional important note is that PCR tests can’t tell the difference between live pathogen or dead! Sometimes, a combination of serologic and molecular tests are ideal when sensitivity is key, such as screening potential blood donors. Prevention of Vector Borne Disease Very few vector borne infections have available vaccines or medications for disease prevention. One that does have commercially available vaccine is Lyme disease. Lyme vaccines are considered “conditional” vaccines, but should be considered for dogs that live in or travel to Lyme endemic regions. Additional factors may even further support vaccination, such as time spent outdoors (eg, a hunting dog has more reason to be vaccinated for Lyme than an apartment dweller) or breed (eg, retriever dogs are more likely to suffer the most serious consequences of Lyme nephritis) . While this talk has focused on tick-transmitted infections, heartworm disease is also an extremely important vector-borne disease. Regular administration of prophylaxis kills the early stage larvae after mosquito bite transmission to prevent the larvae from developing into more mature parasites. For most vector borne diseases, the best prevention is prevention of vectors. Even in the case of heartworms this may be true, with increased emphasis on prevention of mosquito bite in addition to simply killing the immature parasite once transmitted. Flea and tick and tick prevention should ideally be used on all dogs and cats year round. There are many options for ectoparasite control, with more options in dogs than cats. Pyrethroids, phenylpyrazoles, formamidines, and isoxazoline compounds can all be used on pets. These are available as pills, topicals (sprays, spot-ons, shampoos), or collars. Not all have equal efficacy on all arthropod vectors, and even those effective for ticks do not possess equal efficacy against all species of ticks. For example, the Lone Star Tick (Amblyomma americanum) is especially difficult to kill. A variety of considerations should apply when recommending these products to pet owners, including:

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• Spectrum of efficacy • Repellency • Speed of Kill • Owner Compliance o Ease of application o Frequency of application o Aesthetic considerations o Cost • Efficacy throughout treatment interval No preventative regimen is perfect. Environmental controls can also be useful. In the case of fleas, insect growth regulators are enormously useful but on occasion the house may need direct decontamination as well. For tick infestations of buildings, it is best to call on professional pest control help. Keeping the lawn mowed and removing unwanted vegetation can help reduce ticks nearby homes. Regular inspection of pets for pests is also warranted, especially after likely environmental exposure such as a walk in the woods on a spring day. Pets will still be exposed to vector parasites. It is incumbent on us as veterinarians to be aware of the potential pathogens in our area, to ask about travel histories in sick pets, and to know the ideal methods and limitations of testing for vector borne diseases. Further, because many of these infections are indirect or direct zoonosis, it is important that we be prepared to discuss the public health concerns associated with vector transmitted pathogens (table 4). Finally, it is important to realize that the vectors themselves are zoonotic pathogens. While it is unlikely that a human would develop anemia related to fleas or ticks like a small pup or kitten might, these vectors can cause serious disease in the people living with infested pets. As an example, a person bitten by Lone Star ticks may develop a life-long hypersensitivity reaction to red meat that could result in not only morbidity and even potential mortality, but could drastically alter the way the sensitized person must live their life. Table 4: Important Zoonotic Vector Transmitted Infections of Dogs and Cats in the USA Indirect zoonosis (vector required) Direct Zoonosis (vector not required) Lyme disease Bartonellosis Ehrlichiosis Plague Anaplasmosis Q fever Rocky Mountain spotted fever Tularemia Trypanosomiasis Leishmaniasis Heartworm (rare aberrant migration in humans) References available by request. Suggested readings:

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Chomel B. Tick-borne infections in dogs â&#x20AC;&#x201C; An emerging infectious threat. Veterinary Parasitology. 179(4):294, 2011. Dantas-Torres, Filipe, and Domenico Otranto . Best practices for preventing vector-borne diseases in dogs and humans . Trends in parasitology 32.1 (2016): 43-55. Day MJ. One health: the importance of companion animal vector-borne diseases. Parasites and Vectors 4(49), 2011. Day, Michael J . Cats are not small dogs: is there an immunological explanation for why cats are less affected by arthropod-borne disease than dogs? . Parasites & vectors 9.1 (2016): 507. Liu, J., et al . Comparative Evaluation of Two In-clinic Assays for Vector-Borne Disease Testing in Dogs . Topics in Companion Animal Medicine (2018). Maggi RG, Birkenheuer AJ, Hegarty BC, et al. Comparison of serological and molecular panels for diagnosis of vector-borne diseases in dogs. Parasites and Vectors. 7:127, 2014. Otranto D, Dantas-Torres F, Breitschwerdt EB. Managing canine vector-borne diseases of zoonotic concern: part one and part two. Trends in Parasitology. 25(4 &5): 157, 228, 2009. Sherrill, Meredith K., and Leah A. Cohn . Cytauxzoonosis: diagnosis and treatment of an emerging disease . Journal of feline medicine and surgery 17.11 (2015): 940-948. Wardrop KJ, Birkenheuer AJ, Bliais MC, et al. Update on canine and feline blood donor screening for blood-borne pathogens. Journal of Veterinary Internal Medicine, 30(1):15, 2016. Wright I. Practical considerations in parasite control programs for cats and dogs. Companion Animal 20(5):256, 2015. Yancey, Caroline B., et al . Regional seroreactivity and vector-borne disease co-exposures in dogs in the United States from 2004â&#x20AC;&#x201C;2010: utility of canine surveillance . Vector-Borne and Zoonotic Diseases 14.10 (2014): 724-732.

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Companion Animal

William D. Saxon, DVM, DACVIM, DACVECC

IDEXX Reference Laboratories Internal Medicine Consultant Graton, Maine

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With SDMA On average, 40% loss of function

Creatinine testing alone

75% loss of function

Sources 1. Nabity ,MB, et al. Symmetric dimethylarginine assay validation, stability, and evaluation as a marker for the early detection of chronic kidney disease in dogs. J Vet Intern Med. 2015;29(4):1036–1044. 2. Hall JA et al. Serum concentrations of symmetric dimethylarginine and creatinine in dogs w ith naturally occurring chronic kidney disease. J Vet Intern Med. 2016;30(3):794–802. 3. Hall JA, et al. Comparison of serum concentrations of symmetric dimethylarginine and creatinine as kidney function biomarkers in cats w ith chronic kidney disease. J Vet Intern Med. 2014;28(6):1676–1683.

As little as 25% loss of function

40%

75%

SDMA is more sensitive: SDMA increases earlier than creatinine.

Why is SDMA more reliable than traditional diagnostics?

Bill Saxon, DACVIM, DACVECC Idexx Field Medical Specialist

So the SDMA is increased. Now What?

Microalbuminuria • Urine test • False positives • Not specific for kidney

UPC • Urine test • False positives with UTI • Can be normal with kidney disease

Specific Gravity • Urine test • Later marker • Affected by other factors and diseases (e.g. diabetes)

Source: Hall JA, Yerramilli M, Obare M, Yerramilli M, Melendez LD, Jew el DE. Relationship betw een lean body mass and serum renal biomarkers in healthy dogs. J Vet Intern Med. 2015;29(3):808–814.

Source: Hall JA, Yerramilli M, Obare E, Yerramilli M, Yu S, Jew ell DE. Comparison of serum concentrations of symmetric dimethylarginine and creatinine as kidney function biomarkers in healthy geriatric cats fed reduced protein foods enriched w ith fish oil, Lcarnitine, and medium-chain triglycerides. Vet J. 2014;202(3):588–596.

SDMA is more specific: Creatinine is impacted by lean body mass but SDMA is not.

Why is SDMA more reliable than traditional diagnostics?

GFR • Expensive • Not practical • Rarely done in practice

BUN • Late marker • Impacted by other factors including diet, liver disease

Creatinine • Late marker • Impacted by other factors including muscle mass

Limitations of traditional kidney diagnostics

Now available from IDEXX Reference Laboratories. Catalyst® SDMA available late 2017.

o SDMA = Symmetric dimethylarginine o Methylated form of arginine in intracellular proteins of all nucleated cells o Released into circulation when intracellular proteins are processed o Stable production of SDMA is part of daily cell activity o Excreted by the kidneys o A proven renal biomarker that that has been shown to correlate with glomerular filtration rate (GFR) in humans, dogs, and cats

What is SDMA?

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Sources 1. Lulich JP, Osborne CA, O'Brien TD, Polzin DJ. Feline renal failure: questions, answ ers, questions. Compend Contin Educ Pract Vet. 1992;14(2):127–153. 2. Brow n SA. Renal dysfunction in small animals. The Merck Veterinary Manual w ebsite. http://w w w.merckvetmanual.com/mv m/ur inary_system/noninfectious_diseases_of_the_urinary_system_in_s mall_animals/renal_dysfunct ion_in_s mall_anim als.html. Updated October 2013. Accessed August 2, 2016.

In time, at least 1 in 3 cats1 and 1 in 10 dogs2 will develop some form of kidney disease in their lifetime.

Because kidney disease is common!

Why should you run SDMA in all patients?

Endorsement by IRIS

Human field takes interest in SDMA

“Creatinine is so 1950s.”

Preanesthetic screening

Preventive screens during wellness visits

Diagnostic testing for clinical signs of kidney disease

Treatment for hyperthyroidism

Diagnostic testing for clinical signs of other illnesses

When do we diagnose dogs and cats with kidney disease?

Over 40 peer-reviewed publications

How do I know it is accurate?

…results are clinically actionable.

Case study: Molly

…is for all patients in all cases.

…increases with active and acute kidney injury.

…allows for early diagnosis and management of CKD.

IDEXX SDMA® Test…

When should you run SDMA on your patients?

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History o Healthy, from breeder at 2 months o Indoor/outdoor Pacific Northwest suburb o Vaccinations complete, including leptospirosis and rabies o Using Revolution®, recently added Comfortis® o Kirkland Signature® puppy food o Occasional household urinary accidents

Presenting reason: Ovariohysterectomy (OVH)

7-month-old, intact female Shih Tzu

Molly

o Signalment o Clinical signs: appetite, weight loss, vomiting, polyuria/polydipsia (PU/PD) o Duration of clinical signs o Physical examination findings: hydration status, renal palpation o Documentation of azotemia previously o Urinalysis! o Exposure to medications, toxins o Exposure to and protection from infectious diseases

Need clinical information:

Can we diagnose Molly with CKD?

Diagnostic plan o Complete blood count (CBC) o Chemistry panel including the IDEXX SDMA Test

Physical examination o Bright, alert, responsive, hydrated o Temperature, pulse, respiration normal o Body condition score 5–6/9 o Weight of 6.6 lb (3 kg)

Molly’s physical examination

Important to determine if active injury is present that could potentially be treated and reversed.

CKD is irreversible and often progressive

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≤ 16 µg/dL

Delay the spay and follow the IDEXX SDMA Test diagnostic algorithm 21

Do radiographs?

Urine culture?

Measure blood pressure?

Recheck in a few weeks?

Do the spay?

Ignore the SDMA?

IDEXX SDMA® Test diagnostic algorithm

Kidney disease probable: Follow IMM protocol

≤ 14 µg/dL

What should be done now?

IDEXX SDMA® Test diagnostic algorithm

Puppyhood depends on breed and size.

SDMA reference interval in puppies is higher than in adults

www.idexx.com/sdma

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Etiologies o Infectious: pyelonephritis, leptospirosis, Lyme disease o Familial: renal dysplasia o Toxic: jerky treats, grapes, raisins, medications o Glomerulonephritis o Tubulointerstitial disease o Nephrolithiasis o Neoplasia

Differential diagnoses Acute kidney injury versus chronic kidney disease

Assessment Kidney disease probable – act immediately!

Molly’s diagnostic assessment

What if Molly’s SDMA result had been 18 µg/dL?

Hydration status Blood pressure Urine protein:creatinine ratio Thyroid status

For confounding conditions, assess:

• Urine culture and MIC • Diagnostic imaging (stones, • susceptibility pyelonephritis) • • Infectious disease testing • History/possibility of toxin • (Lyme disease, leptospirosis, exposure? • ehrlichiosis, FeLV, FIV, FIP, • History/exposure to potentially toxoplasmosis) nephrotoxic drugs?

To identify an underlying cause, perform:

Molly: Investigate

Consider other evidence of kidney disease: o Inappropriate urine specific gravity (USG) of <1.030 in a dog or <1.035 in a cat o Active urinary sediment—particularly casts, white blood cells, or bacteria o Proteinuria or urine protein:creatinine (UPC) ratio >0.5 in a dog or >0.4 in a cat o History of weight loss, decreased appetite, polydipsia, polyuria o Physical examination findings, such as palpable kidney abnormalities o Creatinine, BUN, and/or phosphorus above reference interval o Creatinine increasing within reference interval o Anemia o Other diagnostic findings (abnormal kidney imaging, unexplained hypertension)

Look for other evidence of kidney disease

Kidney disease probable: Follow IMM protocol

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Right kidney

Pelvic dilation

Left kidney

Pelvic dilation

o Avoid potentially nephrotoxic drugs o Buprenorphine for analgesia

Photo courtesy of Dr. Jennifer Hess, DVM, DACVA

Conclusions o Renal dysplasia o Concurrent pyelonephritis

Findings o Kidneys both slightly small o Mild bilateral renal pelvic dilation o Renal cortices are mildly thinned

• Blood pressure, heart rate and rhythm, oxygenation, ventilation, and body temperature

o Monitor

• Active warming devices

o Prevent hypothermia

• Supplemental oxygen

o Maintain oxygen-carrying capacity

• Intravenous (IV) fluids

o Ensure adequate oxygen delivery to the kidneys o Maintain perfusion

Anesthetizing Molly for her spay

August 2015

Molly’s ultrasound

• Kidney function has returned to normal • Monitor confounding conditions and other underlying disease if present

• If SDMA and creatinine are stable, chronic kidney disease (CKD) is diagnosed • Initiate appropriate treatment based on International Renal Interest Society (IRIS) CKD staging

SDMA remains increased but stable

Recheck in 2 weeks

Monitor as indicated

SDMA returns to normal

Underlying or confounding disease not identified

Underlying or confounding disease identified

Molly: Monitor

Urine culture and MIC susceptibility o Not performed and Molly was treated empirically o Best practice to confirm infection and choose appropriate long-term antibiotic

Molly

SDMA continues to increase • If SDMA and/or creatinine are increasing, consider ongoing, active kidney injury • Perform additional diagnostics to determine cause and to guide treatment

• Underlying disease if identified • Clinical dehydration • Persistent hypertension • Persistent proteinuria • Hyperthyroidism

Treat appropriately

Molly: Manage

• Feed kidney-supportive diet • Provide fresh, clean water sources • Discontinue all potentially nephrotoxic drugs if possible

Provide kidney support immediately

• Provide intravenous fluids, before, during, and upon recovery • Provide oxygen, before, during, and upon recovery • Maintain and monitor blood pressure and body temperature • If needed, use narcotic for pain management

Adjust anesthesia protocols

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Azotemia o Urinary system one of the ‘Big 4” – evaluate in all emergency patients o SDMA most sensitive and specific test for GFR o Increased SDMA (with or without increased BUN, creatinine) = azotemia o Clinicians must not equate azotemia with kidney disease o Prerenal, renal, and postrenal causes of azotemia ALL common

SDMA o Sensitive – detects as little as 25% loss of function. o Early indicator of functional loss often increasing before other parameters. o More reliable than creatinine, not influenced by confounding conditions. o Increase may indicate concurrent disease that my impact kidney function.

USG – what is ‘normal’? o Dog >1.030 o Cat >1.035 o Any USG can be normal depending hydration and other factors o Normal USG does not rule out kidney disease

• 2/3 nephron function loss before lose concentrating ability

o USG necessary to characterize azotemia

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Concentrated urine: USG >1.030 dog, >1.035 cat

o No azotemia

• ‘Normal’ • Up to 2/3 loss of kidney function

o Azotemia

• Prerenal • Renal in cats – USG sometimes 1.040-1.045 with CKD

Proteinuria o Screen all patients o Important cause of kidney injury, morbidity, mortality (IRIS update 2015) o Determine if prerenal, renal, or postrenal o If renal obtain a urine protein:creatinine ratio o If UPC increased (>0.5 dog, >0.4 cat) investigate • • • • •

o Conclusion – better than dilute urine but does not rule out kidney disease o If initial azotemia resolves with fluid therapy → prerenal o If not → investigate causes of kidney disease

Urine chemistries – what matters, what doesn’t

Fresh is best with sediment examination – required. o o o o o o o o

Acute kidney injury – hot topic

Chronic inflammatory disease – neoplasia, skin, dental, etc. Infectious disease – heartworm, tick borne, endocarditis, pyelonephritis Blood pressure Fundic examination Telmisartan (not losartan) or benazepril

Specific gravity – stable Urine protein - stable pH – stable to increased Crystals – struvite, calcium oxalate increase Bacteria – increase or burst RBCs, WBCs – decrease Casts - decrease Epithelial cell morphology – changes

AKI – insult or injury not ‘failure’ o Role of SDMA and complete urinalysis in diagnosis

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AKI ↔ CKD, repetitive acute insults from many diseases

Dogs with CHF

Cardiomyopathy and AKI in cats o NT-proBNP and SDMA higher in cats with CHF (vs asymptomatic CM and healthy). o Cats the died had higher NT-proBNP and SDMA but not creatinine vs survivors. o Conclusions* • Cardiomyopathy is a cause of kidney disease in cats • ‘SDMA is a novel biomarker in cats with CHF and primary CM that could be used for disease management and prognostication.

*Mengmeng, Liu, et al. ACVIM, 2018 Cowgill et al. VCNA-SAP, 2016.

AKI – risk factors o Age – very young or old o Preexisting kidney disease o Dehydration o Diuretic or nephrotoxic drug therapy

AKI – first line of defense

o Protect kidneys to prevent or minimize damage caused by kidney insult or injury o Prerenal – including decreased renal perfusion from sedation

o Postrenal – including ureteral calculi in cats and urinary tract rupture! • Ureteral calculi – fluids, +/- mannitol, +/- prazosin, stent, surgery

o Hypokalemia or hypercalcemia

o Intrinsic/renal – including nonazotemic patients, eg., acute NSAID exposure

o Sepsis

o Monitor after recovery from acute event

o Congestive heart failure o Systemic hypertension

AKI – biomarkers for detection, old and new.

AKI – early recognition

o Kidney function

o Granular casts

• SDMA, creatinine, BUN • Urine specific gravity • Urine protein

o Acute kidney injury • • • • • •

Urine sedment Urine protein (Clusterin) (Cystatin C) (Inosine) Others ?

o Kidney epithelial cells o Glucosuria with normoglycemia o Proteinuria (tubular) o Decreased USG

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AKI or CKD? Nothing on the biochemical profile differentiates them.

Oliguria / anuria --- ER challenge o Normal urine production 1-2 ml/kg/h minimum o Oliguria <0.25 ml/kg/h o Requires indwelling catheter with closed collection system o Place in all unstable patients o Decreased urine production reliable early indicator of clinical deterioration

Oliguria – steps to take

Oliguria - specifics

o Collection system intact and patent → not kinked, clotted, or disconnected

o 5% body weight over 2-4 h

o IV fluids for dehydration, hypovolemia, and hypotension → correct physiologic oliguria o IV fluids at 5% body weight over 2-4 h → correct subclinical dehydration o Lasix x 2 o Mannitol x 2 o Ins and outs o Renal replacement therapy, e.g., dialysis

• E.g. 20 kg x 0.05 = 1 kg = 1 L • If hydration and blood pressure normal →

o Lasix

• 2-6 mg/kg or 2 mg/kg IV than 0.2-0.5 mg/kg/h CRI • Repeat bolus in 1 h if no response • If no response in 1 more h lasix ineffective →

o Mannitol

• 0.5 g/kg IV over 20 minutes • Repeat in 1 h if no response • If no response in 1 more h mannitol ineffective

Ins and outs – strict definition

In and outs – specifics for 20 kg dog, normal hydration, no v/d

o Give volume of fluids that exactly matches losses to avoid volume overload

o 6 h increments

o Insensible loss (respiration, feces) 20 ml/kg/d

o Insensible loss 20 ml/kg/d / 4 = 5 ml/kg x 20 kg in 6 h period = 100 ml

o Sensible loss (urine)

o Urine produced in preceding 6 h = 0 ml

o Losses from vomiting / diarrhea

o No v/d = 0 ml

o Total losses determine fluid volume to administer

o 100 ml total volume to administer over next 6 h = 17 ml/h

6 hours later….

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She produced urine!

Myth – fluids improve kidney function

o Insensible loss over 6 h = 100 ml

o Restore/maintain hydration

o Urine produced in preceding 6 h = 50 ml

o Normalize blood volume and renal perfusion

o Vomitus = 40 ml

o May dislodge ureteral calculi and tubular ‘debris’

o 190 ml total volume to administer over next 6 h = 32 ml/h

o Improve signs of uremia

o 50 ml in 6 h for 20 kg dog

• 8 ml/hr / 20 kg = 0.4 ml/kg/h → no longer oliguric but not normal (1-2 ml/kg/h)

o Correct electrolyte and acid/base imbalance o DO NOT IMPROVE KIDNEY FUNCTION – cellular repair if basement membrane intact o Aggressive diuresis once above corrected not useful o SQ fluids for CKD – only to maintain hydration and appetite

Don’t be afraid of LARGE volume of fluid when indicated…

o 35 kg dog with CRF that presents for vomiting; now weights 32 kg • 2 x maintenance fluids

• 1.5 ml/kg/hr x 2 = 105 ml/hr

• 3 kg = 3 L deficit • Preferably give over 4-6 hrs • 500 ml/hr

• Total = 605 ml/hr for 6 hrs, then drop back down to 105 ml/hr

Leptospirosis – atypical presentations to be aware of… o Respiratory disease o Hepatic disease (without kidney involvement) – can be asymptomatic o Pu/pd only (no azotemia) – can be asymptomatic shedders o Hyposthenuria (USG <1.008) o Doxycycline 10 mg/kg/d x 14 d o Treat other dogs in household even if no clinical signs (asymptomatic shedding) o PCR on whole blood and urine in vaccinated animals pre treatment

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Why proteinuria matters o Persistent renal proteinuria is an initiating and progressive factor in chronic kidney disease o Greater renal morbidity, renal mortality, all cause mortality o Risk greater with increasing magnitude o Cats – death/euthanasia 2.9x with UPC 0.2-0.4; 4x if >0.4

Proteinuria – make sure it is RENAL

Determining the cause – ‘antigen search’

o Renal = glomerular = biggest concern

o Investigate for underlying/primary disease • CBC/biochemistries • Urine culture/sensitivity • Infectious disease screen • Source of inflammation – oral cavity/skin • Neoplasia

o Pre-renal – marked hyperglobulinemia? o Post-renal – most common, rule out lower urinary tract inflammation (sediment exam!)

o Urine protein/creatinine ratio (UP/C) is a MUST

o If UP/C >2– begin treatment while investigating

Proteinuria – new UP/C guidelines for starting treatment

Proteinuria – standard treatment

o >0.5 persistently (>0.4 in cats)

o Renal diet

o If >2 START TREATMENT

o Benazepril or enalapril, 0.25-0.5 mg/kg q12-24 h starting dose (max 2 mg/kg/d)

o 0.2-0.5 = borderline, monitor frequently

o Telmisartan, 1 mg/kg/d, (max 2 mg/kg/d)

o Regardless of whether azotemia present or not (2015 IRIS guideline update) o If UP/C > 2 begin treatment NOW

o Omega-3 fatty acid, 0.25-0.5 mg/kg/d EPA/DHEA o Aspirin, albumin < 20 g/l (2.0 g/dl), 1-5 mg/kg/day dog (1 mg/kg q72 h cat) o Amlodipine - after maximal safe dose of ACEI/telmisartan • Dog 0.1-0.5 mg/kg q24 h • Cat <4 kg 0.625 mg/cat/d • Cat ≥ 4 kg 1/25 mg/cat/d

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Telmisartan – angiotensin receptor blocker

Treatment goal – UP/C

o Telmisartan 1 mg/kg/d

o UP/C <1

o Add to benazepril/enalapril if poor response or reasonable first choice

o UP/C less than 50% of baseiine

o Creatinine 5-7 days after start/dose change

o No side effects

• Also for hypertension

o Reversible gastrointestinal side effects o People – combined ACEi/ARB increases risk of severe hyperkalemia

Options for nonresponders

WSAVA recommendation #1

o Further/repeat investigation for underlying cause

o Biopsy CONTRAINDICATED when • IRIS stage 4 • Comorbidity – coagulopathy, pyelonephritis • Unlikely to change treatment/prognosis

o Renal biopsy o Immunosuppressive therapy o therapy

Relative contraindications – lack of expertise at procuring and/or ANALYZING tissue

WSAVA recommendation #2

WSAVA recommendation #3

o Immunosuppressive treatment CONTRAINDICATED when • Proteinuria not definitively glomerular • Concurrent diabetes mellitus, hypertension… • Signalment suggests non immune-mediated • Amyloidosis likely

o Consider immunosuppressive therapy when • Creatinine >3 mg/dl, 265 umol/l • Severe hypoalbuminemia in spite of standard treatment • Rapidly progressive disease • Immune complexes in 48% biopsy samples • Hence, 1 out of 2 chances i.s. therapy helpful

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WSAVA recommendation #4

Proteinuria – when to add immunosuppressive drug?

o Above all do no harm o Immunosuppressive therapy without biopsy only after discussing pros and cons with client and only with close monitoring

o Severe hypoalbuminemia despite standard treatment o Creatinine >3.0 mg.dL o Rapidly progressive disease o Immune complexes in 48% of biopsy samples – 50:50 chance of benefit

Which immunosuppressive drug(s)?

Proteinuria with severe azotemia...

o Mycophenolate, 10 mg/kg q12h

o Focus on azotemia

o Prednisone, 1 mg/kg q12h, taper as soon as possible

o Chlorambucil, 0.2 mg/kg SID-QOD

o Azathioprine, 2 mg/kg SID

o Standard treatment for acute or chronic kidney disease o Precipitous drop in GFR if use benazepril or enalapril or aspirin o Use amlodipine if hypertension o Omega-3, vitamins C/E/beta carotene okay

Monitoring therapy o Creatinine/SDMA • 5-7 days after start/dose change o UP/C • 4-8 weeks after start/dose/regimen change o With immunosuppressive therapy • First no later than 1-2 wk • Then q2 wk for first 4-6 wk • Then q 4 weeks for 3 mo • Then quarterly

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UTI Prevalence o Dogs

• 14% over lifetime • • • •

• More common in neutered dogs Indwelling urinary catheter, 63% Hyperadrenocorticism, 46% Diabetes mellitus, 37% Intervertebral disc disease, 20-40%

o Cats

• <15% positive aerobic culture with lower urinary signs • CKD, 17-29% • Diabetes mellitus, 12% • Hyperthyroidism, 12%

Common Bugs

Clues (or not) from complete urinalysis

o Single bacteria >70% cases

o Bacteriuria • 20% misidentified degraded casts, cells, crystals, stain precipitates

o E. coli 37-45% o Gram positive (Staph, Strep, Entero) 25-30%

o Struvite crystals

• Infection – not all • Normal finding, concentrated urine • Also oxalates

o Polymicrobial up to 30% o Yeast/fungus or uncommon bacteria • Uncommon • Immunocompromise/predisposing factor(s)

o pH – alkaline urine not specific for infection • Urease-splitting Staph/Proteus • Alkaline urine w/o infection, infection with acidic urine o Pyuria +/- hematuria – not specific • Infection • Inflammation, calculi, neoplasia

Aerobic culture o Cystocentesis gold standard • >103 cfu/ml diagnostic o Catheter sample • Risk of introducing bacteria • >104 cfu/ml male dogs • >105 cfu/ml female dogs • >103 cfu/ml cats o Voided, free catch – cannot be interpreted

Culture Of Uroliths/Bladder Mucosa? o o o o

Aerobic urine culture gold standard Negative urine culture – is infection elsewhere? Culture stones/bladder mucosa if performing cystotomy or cystoscopy Yield may be questionable

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Bacteriuria seen but culture negative… o They weren’t bacteria o Growth inhibited o Fastidious growth requirements

ISCAID says… o Antimicrobial Use Guidelines for Treatment of Urinary Tract Disease in Dogs and Cats: Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases

o Consider gram stain, +/o Empiric therapy when clinically indicated • With what?

Simple Uncomplicated UTI

Short duration high dose therapy

o “Simple uncomplicated UTI is a sporadic bacterial infection of the bladder in an otherwise healthy individual with normal urinary tract anatomy and function.” o Aerobic culture/susceptibility • If susceptible – enrofloxacin 20 mg/kg/d x 3 d o Empiric treatment pending results if needed • Amoxicillin, 11-15 mg/kg q8h for 7 d • Trimethoprim-sulfa, 15 mg/kg q12h for 7 d

o Enrofloxacin 18-20 mg/kg PO q24h x 3 d o Clavamox® 13.75-25 mg/kg PO q12h x 14 d o Equally effective for simple uncomplicated UTI dogs

o SDHD – better compliance, less antibiotic resistance?

Westrop JL, et al. JVIM 2012

Complicated UTI

Treating a complicated UTI

o “A complicated UTI is an infection that occurs in the presence of an anatomic or functional abnormality or a comorbidity that predisposes the patient to persistent infection, recurrent infection, or treatment failure.” o Reinfection – different organism within 6 months of successful treatment o Relapse – same organism within 6 months • Failure to completely eradicate organism

o o o o o o

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If empiric therapy prior to culture results – used different drug than previous 4 week duration (shorter may be effective) Culture 5-7 d into and 7 d after end of tx Pulse therapy, chronic low dose therapy – no Cranberry extract +/- D-mannose – yes PPA, probiotic - maybe

Pyelonephritis o Fluoroquinolone as empiric therapy pending culture results – cover gram negative enterics o 4-6 weeks duration (shorter may be adequate) • 10-14 d course under review by ISCAID o Culture after 7 days of therapy o Culture 7 (and 21?) days after end of therapy o Enrofloxacin – 20 mg/kg/d dogs, 5 mg/kg/d cats

Culture Negative ‘Occult’ Pyelonephritis o Infection in renal tissue, urine of renal pelvis o Renal ultrasound may be supportive o Empiric treatment • Enrofloxacin 20 mg/kg/d x 2 wk, dog (5 mg/kg/d cat) • Amoxicillin/clavulanate 12.5 mg/kg bid x 2 wk • Continue for 6 weeks if response

Subclinical bacteriuria

Treatment rarely indicated when…

o “Subclinical bacteriuria is the presence of bacteria in the urine as determined by positive bacterial culture, in the absence of clinical and cytological evidence of UTI.”

o Bacteriuria with no clinical signs of lower UTI

o Treatment may not be indicated even if MDR • MDR organism may be replaced by susceptible organism o Consider treatment if comorbities, risk for ascending/systemic infection

o Pyuria / active sediment with no clinical signs o Multi-drug resistant organisms are cultured – not more likely to cause infection o Infection control or spread (urine shedding) is the goal o Consider treating subclinical bacteriuria if • High risk of ascending or systemic infection • Patient unable to show clinical signs, eg, spinal cord injury • Corynebacterium urealyticum – risk of encrusting cystitis •

Critically Important Antimicrobials

Fosfomycin tomethamine

o Sole or one of few agents to treat serious human disease; organism transmitted by or acquire resistance from non-human sources

o o o o o o o

o Human CIAs • Carbapenems, fosfomycin, vancomycin

Multidrug-resistant E. coli emerging disease Need for safe, effective, inexpensive drug Bactericidal, broad spectrum Not susceptible to any class of beta lactamases Renal excretion as unchanged drug Distribution into kidneys, bladder wall, prostate 97.5% isolates susceptible

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Fosfomycin – how to administer – NOT CATS o Comes as 3 gm packet of granules o Dose – 40 mg/kg bid dissolved in water or with food • Food enhances bioavailability/duration in urine o Length of treatment – single dose in humans, 1 week in dogs o Mild/moderate diarrhea in 4/12 dogs o Nephrotoxic to cats

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Food Animal

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Food Animal

Daniel Givens, DVM, PhD, DACT, DACVM Professor and Associate Dean for Academic Affairs Auburn University - College of Veterinary Medicine Auburn, Alabama

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Beef Session

Moderators: Randall Spare, Dave Sjeklocha, Eric Behlke

Does modified-live viral vaccine administration to heifers or cows lack substantial risk? M. Daniel Givens,1 DVM, PhD, DACT, DACVM (Virology); Benjamin W. Newcomer,2 DVM, PhD, DACVIM, DACVPM (Epidemiology) 217 Veterinary Education Center, Department of Pathobiology, College of Veterinary Medicine, Auburn University, AL 36849 Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, AL 36849 Corresponding author: Dr. M. Daniel Givens; givenmd@auburn.edu Abstract

Modified-live viral (MLV) vaccines are an important tool to limit reproductive loss subsequent to infection from bovine viral diarrhea virus and bovine herpesvirus-1, but are not without risk. Therefore, their utilization must be undertaken with an understanding of the inherent risks of the vaccines and their administration. These risks include the potential causation of undue harm and lack of effective immunization. Consequently, vaccine programs should be designed to minimize the risks while maintaining or maximizing potential benefits of vaccination. The risk of viral transmission from vaccinated calves to naïve cows is low but not absent. Therefore, cows and heifers should be effectively immunized prior to gestation, ideally at least 30 days before breeding. Additionally, revaccination of pregnant cows previously vaccinated with the same MLV vaccine carries a low but detectable risk of adverse reproductive consequences. Understanding the level of risk associated with the vaccination of cattle against bovine viral diarrhea virus and bovine herpesvirus-1 will aid in the optimization of vaccination protocols. Proper timing of MLV vaccine administration can maximize protection against reproductive viral pathogens while minimizing the potential for the development of adverse consequences subsequent to vaccination. Key words: bovine, cows, vaccine, risks Résumé

Les vaccins à virus vivants modifiés sont des outils importants pour limiter les pertes en reproduction suite à l’infection des bovins par le virus de la diarrhée virale bovine et l’herpès-virus bovin 1 mais ils ne sont pas sans risque. Par conséquent, leur utilisation doit tenir compte des risques inhérents aux vaccins et à leur administration. Parmi ces risques, les vaccins peuvent causer des dommages indus et immuniser inadéquatement. Les programmes de vaccination devraient donc minimiser ces risques tout en

SEPTEMBER 2017

maintenant ou en maximisant les bénéfices potentiels de la vaccination. Le risque de transmission virale d’un veau vacciné à la mère non exposée est faible mais pas absent. Il faudrait donc immuniser adéquatement les vaches et les génisses avant la gestation idéalement au moins 30 jours avant la reproduction. De plus, la revaccination de vaches gestantes vaccinées auparavant avec le même vaccin à virus vivants modifiés comporte un risque faible mais détectable de conséquences néfastes pour la reproduction. Une compréhension du niveau de risque associé à la vaccination des bovins contre le virus de la diarrhée virale bovine et l’herpèsvirus bovin 1 sera utile pour l’optimisation des programmes de vaccination. Vacciner au bon moment avec des vaccins à virus vivants modifiés peut maximiser la protection contre des pathogènes reproducteurs viraux tout en minimisant le potentiel de développement de conséquences néfastes suite à la vaccination. Introduction

Does modified-live viral (MLV) vaccine administration to heifers or cows lack substantial risk when used in specific management situations in the field? As bovine viral diarrhea virus (BVDV) and bovine herpes virus-1 (BHV-1) cause reproductive loss to the cattle industry in the United States, the specific focus of this review will be subcutaneous or intramuscular administration of multivalent, modified-live viral (MLV) vaccines containing BVDV1, BVDV2 and BHV-1. Currently, MLV vaccines are available against BVDV and BHV-1, often in combination with other viral and bacterial antigens. For BVDV, immunization to prevent viremia and birth of persistently infected (PI) offspring is considered important though more difficult to achieve than prevention of clinical disease. While noncytopathic biotypes of BVDV are more prevalent in cattle populations, only cytopathic biotypes are included in the vast majority of MLV vaccine formulations due to safety considerations, as cytopathic strains of BVDV are not considered to result in BVDV persistent infection.24 Due to the varied field strains of BVDV that may result in fetal infection, 171 43

MLV vaccines containing multiple types and subtypes of this pestivirus are expected to provide superior protection against viral challenge.24 Commercial MLV vaccines containing both BVDV1a and BVDV2 are numerous and generally preferred over the use of monovalent preparations. A meta-analysis26 and a thorough review24 focusing solely on vaccination of cattle against BVDV have been published recently. Infection with BHV-1 can cause endometritis and oophoritis that leads to transient infertility.21,22 Field infections of pregnant cattle with BHV-1 can result in abortion rates as high as 60%. Late-term abortions may occur up to 100 days after initial infection.46 Thus, prevention of infertility and abortions due to BHV-1 is considered important. The RLB 106 strain of BHV-1, a temperature-sensitive virus strain capable of replicating in the nasal mucosa but not systemically, is commercially available for intranasal administration.35 A meta-analysis25 and a thorough review3 focusing solely on vaccination of cattle against BHV-1 have been published recently. In considering risk associated with the administration of MLV vaccines, risk is defined as the likelihood that the vaccine will cause undue harm or lack of effective immunization. When focusing on the potential of vaccination to cause undue harm, the benefit of protection must be weighed against the natural costs and consequences of vaccination which may include stress of cattle due to handling and vaccination, a transient loss in production, and possible injuries to cattle during handling. In appropriately considering the balance of this equation, a critical and accurate assessment should be made of the likelihood that cattle on a specific operation will demonstrate reproductive loss caused by field exposure to BVDV or BHV-1. The prevalence of BVDV within the United States cattle population and the potential to cause reproductive loss appears to be relatively stable, with the average prevalence of 4 PI animals per 1000 head.12,18,27,28,44

The prevalence of BHV-1 within the United States cattle population and the potential to cause abortion is considered significant, although scrutinized in some geographic areas. A tabular summary of published retrospective analyses of the diagnosis of BHV-1 in cases of bovine abortion submitted to veterinary diagnostic laboratories in North America is presented in Table 1. The prevalence of BHV-1 as the diagnosed cause of bovine abortion decreased notably from 1971 to 1992 (24.38% to 5.41%).13,14 This precipitous decrease in the prevalence of BHV-1 as the diagnosed cause of bovine abortion was attributed to increased vaccination of open brood cows, appropriate use of modified-live vaccines, and the development of safer effective vaccines.13 A retrospective analysis of case submissions from 2000 to 2011 demonstrated a slight but significant increase over the study period in the percentage of bovine abortions with BHV-1 as the diagnosed cause.10 However, this study demonstrated a continued decrease in BHV-1 as the diagnosed cause of bovine abortion in comparison with earlier studies. In situations where risk may be considered substantial, alternative immunization protocols may be recommended. Considerations of specific management situations in the field include: (a) vaccination of calves nursing pregnant cows that have not been previously vaccinated, (b) vaccination of heifers or cows shortly prior to breeding, (c) vaccination of pregnant heifers or cows that have not been previously vaccinated, and (d) vaccination of pregnant heifers or cows that have been previously vaccinated. Administration to Calves Nursing Pregnant Cows that have not been Previously Vaccinated

Label precautions for MLV vaccines often include a statement such as â&#x20AC;&#x153;Do not use in calves nursing pregnant

Table 1. Published retrospective analyses of the diagnosis of bovine herpesvirus-1 (BHV-1) in cases of bovine abortion submitted to veterinary diagnostic laboratories in North America. Year of publication

Dates of case submission

1973

172 44

Number diagnosed with BHV-1 197

Number of cases submitted 808

% diagnosed with BHV-1

Comments

Reference

1971

Location of veterinary diagnostic laboratory South Dakota, USA

24.38%

1992

1982-1992

South Dakota, USA

485

8,962

5.41%

2004

1983-2001

Michigan, USA

1,618

3.21%

2013

2000-2011

264

19,459

1.36%

2016

2013-2014

236

3.39%

2016

2007-2013

Iowa, California, Washington, Minnesota, and South Dakota, USA British Columbia, Canada California, USA

BHV-1 was most common viral cause. BHV-1 was most common viral cause. BHV-1 was most common viral cause. Overall, BHV-1 testing was positive in 3.8% of submissions.

709

3.53%

BHV-1 was most common viral cause. BHV-1 was most common viral cause.

13 43 10

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THE AABP PROCEEDINGSâ&#x20AC;&#x201D;VOL. 50

cows unless their dams were vaccinated within the past 12 months as described elsewhere on the label.” The risk is that MLV vaccine administration will result in transmission of attenuated viruses from calves to pregnant dams, causing reproductive loss. As available MLV vaccines contain cytopathic strains of BVDV that have not been demonstrated to cause abortions, the true focus of this risk is BHV-1. A study involving subcutaneous administration of MLV vaccinea to 18 seronegative steers and heifers in contact with 4 seronegative pregnant control cows on 2 acres did not result in transmission (as indicated by absence of seroconversion of the pregnant cows) or reproductive loss.15 Initial intramuscular vaccination of 10 seronegative Hereford heifers with an MLV vaccineb did not result in detected shedding of BHV-1 or transmission to 9 control herdmates.4 Clearly, an intranasally administered, modified-live BHV-1 vaccine strain is more likely to be transmitted from vaccinates to contacted cattle than when the same strain is administered parenterally.20 A recent retrospective field investigation indicated an occurrence of viral transmission and reproductive loss from recently vaccinated and weaned calves to poorly vaccinated cows with which some contact was maintained.3 While the risk of transmission of attenuated viruses from calves to pregnant dams resulting in reproductive loss appears to be relatively low, the risk clearly emphasizes the need to focus effective vaccination protocols on the stimulation of immunity in heifers prior to their first gestation. Administration to Heifers or Cows Shortly Prior to Breeding

Due to concerns regarding the safety of MLV vaccines, label precautions include statements such as, “Administer at or about 4 weeks prior to breeding,” or “Administer to cows 30 days and heifers at least 60 days prior to breeding.” From 1 perspective, administration of MLV vaccine very shortly before breeding appears desirable, as protection from viral reproductive pathogens at, and soon after, the time of breeding is imperative. For many operations, the time of breeding is when cattle from previously separate groups or herds are commingled to increase the size of breeding groups and efficiently achieve pregnancies. This operational strategy creates an opportunity for pathogen transmission to stressed cattle and thus a need for prior effective immunization. Notably, partial protection from clinical disease due to virulent BVDV challenge has been demonstrated in as little as 3 days following a single dose of MLV vaccine, while complete protection against clinical disease due to BVDV may be observed by 5 days following vaccine administration.2,30 Protection against clinical disease due to BHV-1 has been observed within 2 to 5 days following intramuscular vaccination with MLV vaccines.33,34,41 Though no vaccine provides complete protection in all circumstances, recent studies using multivalent MLV vaccines have demonstrated consistent BVDV fetal protection SEPTEMBER 2017

rates in the range of 85 to 100% in randomized, controlled clinical trials.7,9,17,32,42 Recent studies using multivalent MLV vaccines have demonstrated consistent BHV-1 fetal protection rates in the range of 84 to 100% in randomized, controlled clinical trials.8,9 Infection with BVDV shortly before the breeding period has the potential to cause oophoritis, particularly diffuse necrosis within corpora lutea, altered ovarian function, endometritis, reduced conception rates, and increased rates of early embryonic death.3,11,19,23,36 Initial vaccination of naïve heifers with an MLV vaccine very shortly before breeding creates notable risk for negatively impacting reproduction. Initial intramuscular vaccination of 10 seronegative Hereford heifers with an MLV vaccineb 3 days prior to synchronized estrus did not result in detected shedding of BHV-1 or transmission to 9 control herdmates.4 However, after a 35-day breeding season, 6/10 (60%) vaccinated heifers calved compared to 9/9 (100%) unvaccinated controls, which was a significant difference (p=0.034).4 In a more recent study, 21 seronegative heifers were vaccinated with killed viral vaccinec at 36 and 8 days before synchronized timed artificial insemination (TAI; group1), 7 seronegative heifers were vaccinated with killed viral vaccinec at only 8 days before TAI (group 2), 21 seronegative heifers were vaccinated with MLV vaccined at only 8 days before TAI (group 3), and 10 seronegative heifers were maintained as unvaccinated controls (group 4).31 After TAI, heifers were maintained with breeding bulls for 2 weeks. At 61 days after TAI, ultrasonography revealed pregnancy in 19/21 (90%) group 1 heifers, 6/7 (86%) group 2 heifers, 10/21 (48%) group 3 heifers, and 9/10 (90%) group 4 control heifers. The pregnancy rate in group 3 heifers, which received an initial dose of MLV vaccine only 8 days before TAI, was significantly lower than that of groups 1 and 4. Thus, initial vaccination of naïve (seronegative) heifers with MLV vaccine at 8 days prior to breeding is not recommended due to clear demonstration of reproductive risk. Notably, the question is often asked about the risk of revaccination with an MLV vaccine shortly before breeding. One study evaluated the impact on conception rates of 799 Angus crossbred heifers when revaccination with an MLV vaccinee was performed at 40 days (control group) or 3 days (treatment group) prior to breeding.1 This revaccination occurred after at least 2 prior doses of MLV vaccine. At approximately 90 days after initial breeding in this estrus synchronization program in which heifers were only artificially inseminated after an observed estrus, ultrasonography revealed an 85.1% conception rate for controls and 86.4% for treatment heifers, which was not significantly different. This study has been critiqued because no unvaccinated animals were maintained in the research design to assess if the third dose of MLV vaccine administered at 40 days prior to breeding had a negative effect on conception rate.3 Another study evaluated the impact on pregnancy rates of 692 primiparous dairy cows when an MLV vaccinef 173 45

or a killed viral vaccineg were administered 45 days prior to TAI.39 This revaccination occurred after 4 prior doses of MLV vaccine. At 60 days after TAI in the double-Ovsynch-TAI protocol, ultrasonography revealed a 43% pregnancy rate for cows administered killed viral vaccine and 44% for cows administered MLV vaccine, which was not significantly different. In this study, revaccination with killed viral vaccine produced higher antibody titers than MLV vaccine for BHV-1 in the primiparous dairy cows which were between 21 and 28 days-in-milk at the time of revaccination.39 In a third study focused on revaccination with an MLV vaccineh shortly before breeding, 2 groups of 20 seronegative Angus crossbred heifers were vaccinated 2 days after estrus and then revaccinated 30 days later.37 One group of 20 heifers (Group A) was synchronized in estrus at 10 days after revaccination while the other group (Group B) was synchronized in estrus at 31 days after revaccination. A control group of heifers (n=20) did not receive MLV vaccine. Breeding during this synchronized estrus was achieved by natural service. No differences were detected in the characteristics of estrus behavior assessed using radio frequency technology or embryonic loss assessed using ultrasonography. At 40 days after a 45-day breeding season, 14/20 (70%) Group A heifers were pregnant, 17/20 (85%) group B heifers were pregnant, and 19/20 (95%) control heifers were pregnant. These differences in pregnancy rate were not significant. Thus, while caution is prudent, the likelihood of causing undue harm with revaccination shortly before breeding is notably less than the risk from initial vaccination shortly before breeding. Revaccination with MLV vaccines at no less than 30 days before breeding is recommended by the authors to facilitate optimal reproductive performance. Administration to Pregnant Heifers or Cows that have not been Previously Vaccinated

Several MLV vaccines now have label approval for the vaccination of pregnant cattle if and only if certain conditions are met (e.g., vaccination of cattle with the same vaccine during the previous 12 months).24 The fulfillment of these conditions prior to administration of MLV vaccines during pregnancy is critical unless the safety of the vaccination protocol is to depend on the serendipitous field exposure of cattle to BHV-1 prior to pregnancy and vaccination. Vaccination of naïve (seronegative) heifers or cows with MLV vaccine will commonly cause abortion in the following weeks to months.45 Notably, intranasal administration of an MLV vaccine containing a temperature-sensitive mutant, RLB 106, to pregnant cows has been demonstrated not to cause abortion.16 Thus, while initial vaccination of pregnant heifers or cows may not cause undue harm in some previously exposed populations, the risk of abortion due to intramuscular or subcutaneous vaccination of naïve cattle during pregnancy with MLV vaccines is high.

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Administration to Pregnant Heifers or Cows that have been Previously Vaccinated Some available MLV vaccines are labeled for administration to pregnant cattle “provided they were vaccinated, according to label directions, with this same product within the past 12 months.” To achieve this label claim, which was first approved in 2003, the USDA-APHIS Center for Veterinary Biologics (CVB) requires demonstrated safety studies, including large field trials of approximately 1,200 vaccinates, with some pregnancies at each of the 3 stages of gestation. A publication resulting from 1 set of these safety studies demonstrated that adverse events are rare when label directions are followed.6 Yet, some risk of abortion when following label directions has been demonstrated in these large field trials. One abortion attributed to BHV-1 occurred in 235 heifers (0.4%) vaccinated with an MLV vaccine according to label directions during the second trimester of gestation.6 A field investigation indicated an association between vaccination of pregnant cows with an MLV vaccine following label directions and reproductive losses, including BHV-1 abortions.29 A recent review details multiple published manuscripts that infer a notable impact of this demonstrated, though limited, risk.3 As an alternative, a recent study compared the efficacy of annual revaccination of pregnant cows with a multivalent viral vaccine containing temperature-sensitive, modified-live BHV-1 and killed BVDV (combination viral [CV] vaccinei) rather than an MLV vaccinej after 2 pre-breeding doses of MLV vaccinej were initially administered to developing heifers.38 In this research, cows were challenged during their second gestation through both exposure to PI cattle and subsequent intravenous injection with BHV-1. In unvaccinated control cows, 15/15 fetuses were infected with BVDV and/or BHV1 while 11/15 (73%) aborted. Pregnant cows revaccinated annually with MLV vaccinej demonstrated 2/23 (9%) offspring infected with BVDV and another 2/23 (9%) infected with BHV-1, while 3/23 (13%) were aborted. In comparison, pregnant cows revaccinated annually with CV vaccinei demonstrated 0/22 offspring infected with BVDV and 0/22 infected with BHV-1 while 1/22 (5%) were aborted. These differences were significant when comparing the vaccinated groups to the control group. Thus, annual revaccination of previously vaccinated pregnant cows with either an MLV vaccinej or a CV vaccinei facilitated protection against a rigorous viral challenge.38 Conclusions

After careful review of research available from the last 50 years, MLV vaccines containing BVDV and BHV-1 exhibit substantial and commonly unacceptable risk of causing undue harm if administered to previously unvaccinated pregnant heifers or cows, or if administered as the initial dose of MLV vaccine to heifers or cows within 30 days prior to

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breeding. Additionally, MLV vaccines exhibit a low risk when administered to calves nursing unvaccinated pregnant cows. When administered to pregnant cows previously vaccinated with the same MLV vaccine, these vaccines exhibit a low but detectable risk of undue harm. Notably, currently available MLV vaccines provide safe and critically effective protection when administered to developing heifers with the last dose administered at least 30 days prior to breeding. In summary, proper timing of MLV vaccine administration can minimize the risk of undesirable side effects while maximizing vaccine efficacy to facilitate the control of disease due to BVDV and BHV-1. Endnotes

Express 5, Boehringer Ingelheim Vetmedica, Inc., St Joseph, MO b Resbo IBR, Norden/Smithkline Company, Lincoln, NE c ViraShield 6 VL 5 HB, Novartis Animal Health US, Inc., Larchwood, IA d BoviShield Gold FP 5 VL 5, Pfizer Animal Health, Exton, PA e Vista 5 L5 SQ, Intervet, Inc., Millsboro, DE f Express FP 10, Boehringer Ingelheim Vetmedica, Inc., St. Joseph, MO g Triangle 10, Boehringer Ingelheim Vetmedica, Inc., St. Joseph, MO h Express FP 5 VL 5, Boehringer Ingelheim Vetmedica, Inc., St. Joseph, MO i CattleMaster Gold FP5, Zoetis, Florham Park, NJ j Bovishield Gold FP5, Zoetis, Florham Park, NJ a

Acknowledgements

Dr. Givens reports grants and personal fees from Boehringer Ingelheim Vetmedica, Inc., grants from Zoetis, Inc., personal fees from Elanco, personal fees from Boehringer Ingelheim Animal Health GmbH, outside the submitted work. In addition, Dr. Givens isolated a novel cytopathic BVDV1b for vaccine production licensed to Pfizer Animal Health, Inc. Dr. Newcomer reports grants from Zoetis, Inc., outside the submitted work. References

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5. Clothier K, Anderson M. Evaluation of bovine abortion cases and tissue suitability for identification of infectious agents in California diagnostic laboratory cases from 2007 to 2012. Therio 2016; 85:933-938. 6. Ellsworth MA, Brown MJ, Fergen BJ, et al. Safety of a modified-live combination vaccine against respiratory and reproductive diseases in pregnant cows. Vet Ther 2003; 4:120-127. 7. Ellsworth MA, Fairbanks KK, Behan S, et al. Fetal protection following exposure to calves persistently infected with bovine viral diarrhea virus type 2 sixteen months after primary vaccination of the dams. Vet Ther 2006; 7:295-304. 8. Ficken MD, Ellsworth MA, Tucker CM, et al. Effects of modified-live bovine viral diarrhea virus vaccines containing either type 1 or types 1 and 2 BVDV on heifers and their offspring after challenge with noncytopathic type 2 BVDV during gestation. J Am Vet Med Assoc 2006; 228:1559-1564. 9. Givens MD, Marley MS, Jones CA, et al. Protective effects against abortion and fetal infection following exposure to bovine viral diarrhea virus and bovine herpesvirus 1 during pregnancy in beef heifers that received two doses of a multivalent modified-live virus vaccine prior to breeding. J Am Vet Med Assoc 2012; 241:484-495. 10. Gould S, Cooper VL, Reichardt N, et al. An evaluation of the prevalence of bovine herpesvirus 1 abortions based on diagnostic submissions to five U.S.-based veterinary diagnostic laboratories. J Vet Diagn Invest 2013; 25:243-247. 11. Grooms DL, Brock KV, Pate JL, et al. Changes in ovarian follicles following acute infection with bovine viral diarrhea virus. Therio 1998; 49:595-605. 12. Hessman BE, Fulton RW, Sjeklocha DB, et al. Evaluation of economic effects and the health and performance of the general cattle population after exposure to cattle persistently infected with bovine viral diarrhea virus in a starter feedlot. Am J Vet Res 2009; 70:73-85. 13. Kirkbride CA. Viral agents and associated lesions detected in a 10-year study of bovine abortions and stillbirths. J Vet Diag Invest 1992; 4:374-379. 14. Kirkbride CA, Bicknell EJ, Reed DE, et al. A diagnostic survey of bovine abortion and stillbirth in the Northern Plains States. J Am Vet Med Assoc 1973; 162:556-560. 15. Kleiboeker SB, Lee SM, Jones CA, et al. Evaluation of shedding of bovine herpesvirus 1, bovine viral diarrhea virus 1, and bovine viral diarrhea virus 2 after vaccination of calves with a multivalent modified-live virus vaccine. J Am Vet Med Assoc 2003; 222:1399-1403. 16. Kucera CJ, White RG, Beckenhauer WH. Evaluation of the safety and efficacy of an intranasal vaccine containing a temperature-sensitive strain of infectious bovine rhinotracheitis virus. Am J Vet Res 1978; 39:607-610. 17. Leyh RD, Fulton RW, Stegner JE, et al. Fetal protection in heifers vaccinated with a modified-live virus vaccine containing bovine viral diarrhea virus subtypes 1a and 2a and exposed during gestation to cattle persistently infected with bovine viral diarrhea virus subtype 1b. Am J Vet Res 2011; 72:367-375. 18. Loneragan GH, Thomson DU, Montgomery DL, et al. Prevalence, outcome, and health consequences associated with persistent infection with bovine viral diarrhea virus in feedlot cattle. J Am Vet Med Assoc 2005; 226:595-601. 19. McGowan MR, Kirkland PD, Richards SG, et al. Increased reproductive losses in cattle infected with bovine pestivirus around the time of insemination. Vet Rec 1993; 133:39-43. 20. McKercher DG, Crenshaw GL. Comparative efficacy of intranasally and parenterally administered infectious bovine rhinotracheitis vaccines. J Am Vet Med Assoc 1971; 159:1362-1369. 21. Miller JM. The effects of IBR virus infection on reproductive function of cattle. Vet Med 1991; 86:95-98. 22. Miller JM, Van der Maaten MJ. Reproductive tract lesions in heifers after intrauterine inoculation with infectious bovine rhinotracheitis virus. Am J Vet Res 1984; 45:790-794. 23. Miller JM, Van der Maaten MJ. Experimentally induced infectious bovine rhinotracheitis virus infection during early pregnancy: Effect on the bovine corpus luteum and conceptus. Am J Vet Res 1986; 47:223-228. 24. Newcomer BW, Chamorro MF, Walz PH. Vaccination of cattle against bovine viral diarrhea virus. Vet Microbiol 2017. 25. Newcomer BW, Cofield LG, Walz PH, et al. Prevention of abortion in cattle following vaccination against bovine herpesvirus 1: A meta-analysis. Prev Vet Med 2017; 138:1-8.

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26. Newcomer BW, Walz PH, Givens MD, et al. Efficacy of bovine viral diarrhea virus vaccination to prevent reproductive disease: a meta-analysis. Therio 2015; 83:360-365.e361. 27. O’Connor AM, Reed MC, Denagamage TN, et al. Prevalence of calves persistently infected with bovine viral diarrhea virus in beef cow-calf herds enrolled in a voluntary screening project. JAmVet MedAssoc 2007; 230:1691-1696. 28. O’Connor AM, Sorden SD, Apley MD. Association between the existence of calves persistently infected with bovine viral diarrhea virus and commingling on pen morbidity in feedlot cattle. Am J Vet Res 2005; 66:2130-2134. 29. O’Toole D, Miller MM, Cavender JL, et al. Pathology in practice. J Am Vet Med Assoc 2012; 241:189-191. 30. Palomares RA, Givens MD, Wright JC, et al. Evaluation of the onset of protection induced by a modified-live virus vaccine in calves challenge inoculated with type 1b bovine viral diarrhea virus. Am J Vet Res 2012; 73:567-574. 31. Perry GA, Zimmerman AD, Daly RF, et al. The effects of vaccination on serum hormone concentrations and conception rates in synchronized naive beef heifers. Therio 2013; 79:200-205. 32. Rodning SP, Marley MS, Zhang Y, et al. Comparison of three commercial vaccines for preventing persistent infection with bovine viral diarrhea virus. Therio 2010; 73:1154-1163. 33. Sutton ML. Rapid onset of immunity in cattle after intramuscular injection of a modified-live-virus IBR vaccine. Veterinary Medicine/Small Animal Clinician 1980; Volume?:1447-1456. 34. van Drunen Littel-van den H, Tikoo SK, Liang X, et al. Bovine herpesvirus-1 vaccines. Immunol Cell Biol 1993; 71 (Pt 5):405-420. 35. van Oirschot JT, Kaashoek MJ, Rijsewijk FA. Advances in the development and evaluation of bovine herpesvirus 1 vaccines. Vet Microbiol 1996; 53:43-54. 36. Virakul P, Fahning ML, Joo HS, et al. Fertility of cows challenged with a cytopathic strain of bovine viral diarrhea virus during an outbreak of spontaneous infection with a noncytopathic strain. Therio 1988; 29:441-449. 37. Walz PH, Edmondson MA, Riddell KP, et al. Effect of vaccination with a multivalent modified-live viral vaccine on reproductive performance in synchronized beef heifers. Therio 2015; 83:822-831.

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38. Walz PH, Givens MD, Rodning SP, et al. Evaluation of reproductive protection against bovine viral diarrhea virus and bovine herpesvirus-1 afforded by annual revaccination with modified-live viral or combination modifiedlive/killed viral vaccines after primary vaccination with modified-live viral vaccine. Vaccine 2017; 35:1046-1054. 39. Walz PH, Montgomery T, Passler T, et al. Comparison of reproductive performance of primiparous dairy cattle following revaccination with either modified-live or killed multivalent viral vaccines in early lactation. J Dairy Sci 2015; 98:8753-8763. 40. Wilson DJ, Orsel K, Waddington J, et al. Neospora caninum is the leading cause of bovine fetal loss in British Columbia, Canada. Vet Parasitol 2016; 218:46-51. 41. Woolums AR, Siger L, Johnson S, et al. Rapid onset of protection following vaccination of calves with multivalent vaccines containing modified-live or modified-live and killed BHV-1 is associated with virus-specific interferon gamma production. Vaccine 2003; 21:1158-1164. 42. Xue W, Mattick D, Smith L. Protection from persistent infection with a bovine viral diarrhea virus (BVDV) type 1b strain by a modified-live vaccine containing BVDV types 1a and 2, infectious bovine rhinotracheitis virus, parainfluenza 3 virus and bovine respiratory syncytial virus. Vaccine 2011; 29:4657-4662. 43. Yamini B, Mullaney TP, Patterson JS, et al. Causes of bovine abortion in the north-central United States: Survey of 1618 cases (1983-2001). Bov Pract 2004; 38:59-64. 44. Yan L, Zhang S, Pace L, et al. Combination of reverse transcription realtime polymerase chain reaction and antigen capture enzyme-linked immunosorbent assay for the detection of animals persistently infected with bovine viral diarrhea virus. J Vet Diag Invest 2011; 23:16-25. 45. Zemjanis R. Vaccination for reproductive efficiency in cattle. J Am Vet Med Assoc 1974; 165:689-692. 46. Zimmerman AD, Buterbaugh RE, Herbert JM, et al. Efficacy of bovine herpesvirus-1 inactivated vaccine against abortion and stillbirth in pregnant heifers. J Am Vet Med Assoc 2007; 231:1386-1389.

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animal

Animal, page 1 of 7 © The Animal Consortium 2018 doi:10.1017/S1751731118000708

Review: Risks of disease transmission through semen in cattle M. D. Givens† College of Veterinary Medicine, Auburn University, Auburn, AL 36849-5536, USA

(Received 17 December 2017; Accepted 13 March 2018)

The purpose of this paper is to review scientific evidence concerning pathogens that could potentially be transmitted via bovine semen. As a result of a careful analysis of the characteristics of infections that may cause transmission of disease through semen, effective control procedures can be identified that provide minimal constraint to the introduction of new bulls into herds for natural breeding and importation of valuable novel genetics through artificial insemination. The potential for transmission through bovine semen and corresponding effective control procedures are described for bovine herpesvirus 1, bovine viral diarrhea virus, bovine leukemia virus, lumpy skin disease virus, bluetongue virus, foot-and-mouth disease virus, and Schmallenberg virus. Brief consideration is also provided regarding the potential for transmission via semen of Tritrichomonas foetus, Campylobacter fetus venerealis, Brucella abortus, Leptospira spp., Histophilus somni, Ureaplasma diversum, Mycobacterium avium subsp. paratuberculosis, Chlamydiaceae, Mycobacterium bovis, Coxiella burnetii, Mycoplasma mycoides ssp. mycoides and Neospora caninum. Thoughtful and systematic control procedures can ensure the safety of introducing new bulls and cryopreserved semen into cattle production systems. Keywords: cattle, pathogen, semen, venereal, infertility

Implications The characteristics of viral, bacterial, protozoal, and parasitic infections and infestations of cattle vary significantly. Understanding these infections allow effective control procedures that minimally impede optimal cattle production to be thoughtfully enacted. Introduction Some viral, bacterial, protozoal, and parasitic organisms may be transmitted through bovine semen. Infections of a bull’s testicle, epididymis, vas deferens, ampulla, seminal vesicle, prostrate, urethra, penis, or prepuce or the migration or leakage of infected blood cells into the male reproductive tract can readily contaminate semen. In some but not all instances, these conditions may result in (a) detection of DNA or RNA of the pathogen in semen, (b) detection of infectious pathogen in the semen or (c) detection of infectious pathogen in semen sufficient to result in transmission to heifers or cows via natural breeding and/or artificial insemination. Detection of DNA or RNA of the pathogen in semen does not consistently imply that venereal transmission would result from natural breeding or insemination. Often, testing blood samples for absence or presence of antibodies or absence of pathogen will provide confidence that semen from †

E-mail: givenmd@auburn.edu

the bull is free of contamination. Unfortunately, this assessment of blood samples will not always provide clarity regarding the status of semen. Conditions of reactivated, persistent, or prolonged infections increase concern for pathogen transmission via semen as the duration of shedding of infectious pathogen may signiﬁcantly increase the potential for pathogen transmission. Thus, understanding infections of the male reproductive tract provides clarity on how best to prevent disease transmission while facilitating cattle production.

Viral pathogens Transmission via semen has been scrutinized for important viral pathogens including bovine herpesvirus 1 (BoHV-1), bovine viral diarrhea virus (BVDV), bovine leukemia virus (BLV), lumpy skin disease virus (LSDV), bluetongue virus (BTV), foot-and-mouth disease virus (FMDV) and Schmallenberg virus (SBV). Prevention of venereal transmission of these viruses involves understanding the characteristics of various viral infections, appropriate assessments of risk and consistent application of control procedures to mitigate or abolish the potential for viral transmission.

Bovine herpesvirus 1 Bovine herpesvirus 1 (synonym infectious bovine rhinotracheitis/infectious pustular vulvovaginitis virus) can cause 1

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Givens clinical disease of the male reproductive tract (infectious balanoposthitis) and be shed in seminal plasma due to replication in the mucosa of the prepuce, penis, and urethra (Weiblen et al., 1992; van Oirschot et al., 1995; van Oirschot, 1995; Vogel et al., 2004; Wrathall et al., 2006). While BoHV-1 may not affect sperm motility or acrosomal status (Tanghe et al., 2005), others have described an effect on semen quality most likely due to generalized illness rather than a direct effect of the virus on sperm (van Oirschot et al., 1995; van Oirschot, 1995; Vogel et al., 2004). The virus may inhibit sperm-zona binding by interacting with sperm (Tanghe et al., 2005). Bovine herpesvirus 1 can be transmitted through semen and result in infection, reduced conception rates, endometritis, abortion and infertility (Bielanski et al., 1988; van Oirschot, 1995). Once infected, bulls may shed the virus in semen intermittently throughout life though remaining clinically normal (van Oirschot, 1995). However, results suggest that BoHV-1 seropositive bulls can be free of virus for long periods of time if bulls are well managed in a low-stress environment (Eaglesome and Garcia, 1997). To prevent BoHV-1 from contaminating semen, bulls should be maintained in isolation or in a BoHV-1-free herd or artificial insemination center during collection and blood should be tested negative for antibody to BoHV-1 at least 21 days after the last collection of semen that is to be used for insemination. Alternatively, when a bull is seropositive or of unknown serologic status, an aliquot of semen from each collection should be tested negative for virus using an assay validated for semen samples (virus isolation or PCR; Chapter 11.8 of the Office International des Epizooties (OIE) Terrestrial Animal Health Code) (OIE, 2017a). To prevent BoHV-1 in semen from being transmitted, 0.25% trypsin could be added to semen for 5 min at room temperature before processing to inactivate the enveloped virus (Bielanski et al., 1988; Silva et al., 1999; Bielanski, 2007). Alternatively, treatment of BoHV-1 contaminated semen with gamma globulins from hyperimmune serum can neutralize the virus and reduce the risk of viral transmission via artificial insemination without affecting fertility (Wrathall et al., 2006).

Bovine viral diarrhea virus Another important reproductive pathogen, BVDV, can replicate throughout the bull including within the seminal vesicles, prostate gland and epididymis (Kirkland et al., 1991). In addition, BVDV antigen has been detected in sertoli cells, spermatogonia and epithelial cells of the urethra

(Borel et al., 2007; Newcomer et al., 2014). Bovine viral diarrhea virus can be present in semen from bulls with persistent infection, acute (transient) infection, persistent testicular infection and prolonged testicular infection (Table 1). Bulls previously exhibiting acute infections (at up to 28 days after initial infection), persistent testicular infections (at up to 42 months of age), and prolonged testicular infections (at up to 33 months after initial infection) may subsequently produce semen that is free of BVDV (Gard et al., 2007; Givens et al., 2009; Newcomer et al., 2014). Virus has been transmitted to inseminated animals through semen collected from bulls exhibiting persistent infections, acute infections and persistent testicular infections. The defining difference between cases termed ‘prolonged testicular infections’ and those termed ‘persistent testicular infection’ has not been the assessed duration of the testicular infection but the ease with which virus could be isolated from semen and the associated consistency of viral transmission to inseminated cattle (Givens et al., 2009; Newcomer et al., 2014). Extended isolation (quarantine) in association with routine periodic monitoring from presence of detectable virus in semen might be advisable for some valuable bulls diagnosed with persistent testicular infection. Bovine viral diarrhea virus in semen may be associated with sperm and cannot be removed by centrifugation through a percoll gradient, swim-up techniques, glass wool filtration or glass bead filtration (Bielanski et al., 1992). The OIE recommended standards (Chapter 4.6 of the Terrestrial Animal Health Code) require bulls to be free of BVDV in blood on entry into artificial insemination centers with ongoing testing for BVDV and anti-BVDV antibodies during semen collection procedures (Gard et al., 2007). When admitting bulls through an isolation and quarantine procedure, groups of bulls should be assembled, tested and cleared based on all-in and all-out management after assurance that BVDV is not circulating within the group based on serologic evidence. The OIE recommendations necessitate that seropositive bulls produce semen free of BVDV as determined by virus isolation or virus antigen testing. To meet Certified Semen Services (CSS; a subsidiary of the National Association of Animal Breeders to establish industry self-regulation) standards in the United States, bulls must be non-viremic on entry and maintain the non-viremic status. If these non-viremic bulls test seronegative, no semen testing is required (Gard et al., 2007). If bulls are seropositive, at least one sample of semen that is completely

Table 1 Characteristics of infectious with bovine viral diarrhea virus that may result in the contamination of bovine semen with virus Infection

Serologic status Transmission via to infecting strain insemination

Acute infection Persistent infection Persistent testicular infection Prolonged testicular infection

Seroconversion Seronegative Seropositive Seropositive

178 2

Demonstrated Consistently demonstrated Demonstrated Not demonstrated

Viral concentration in semen

Duration of viral shedding in semen

8 to 200 CCID50/ml 1 × 105 to 3.98 × 107 CCID50/ml ⩽ 6.25 × 103 CCID50/ml Detectable only by virus isolation after ultracentrifugation or by RT-PCR

2 to 28 days after infection Throughout life Up to 42 months of age Up to 33 months after infection

Disease risks from bovine semen extended, frozen, and transported to the diagnostic lab at cryogenic temperatures must test negative using a PCR assay (CSS, 2014). Research does clearly indicate that straws of semen should be transported to diagnostic laboratories at cryogenic temperatures (i.e. liquid nitrogen or liquid nitrogen vapor tank) to optimize either PCR or virus isolation assays to detect BVDV in semen (Newcomer et al., 2014).

Bovine leukemia virus Bovine leukemia virus (BLV; synonym enzootic bovine leucosis virus) produces a benign persistent lymphocytosis and infections may eventually cause lymphatic tumors in some adult cattle. A seropositive status is considered evidence for ongoing infection with this Deltaretrovirus. The virus is rarely found in semen though possibly present in association with virus-infected lymphocytes in the genital tract (Choi et al., 2002; Wrathall et al., 2006). While substantial evidence demonstrates that BLV is rarely – if ever – transmitted by artificial insemination, transmission was detected when infected lymphocytes were inoculated into the uterus of seronegative cows (Van Der Maaten and Miller, 1978; Wrathall et al., 2006). To ensure that semen is free of BLV, Chapter 11.6 of the OIE terrestrial animal health code recommends that semen donor bulls be residents of BLV-free herds and come from a serologically negative dam (if less than 2 years of age), or that blood samples from the bull test negative for antibodies against BLV on two occasions, the first being at least 30 days before and the second at least 90 days after collection of semen (OIE, 2017a). Lumpy skin disease virus Lumpy skin disease virus, a member of the genus Capripoxvirus, causes acute, subacute or subclinical disease in cattle. The disease is characterized by firm, circumscribed skin nodules, necrotic plaques in the mouth and nares, fever, and generalized lymphadenopathy. This virus is reported to be endemic in sub-Saharan Africa and Egypt with the potential for spread to other parts of Africa, the Middle East, and Europe (Irons et al., 2005; Annandale et al., 2014). After experimental infection, LSDV could be isolated from semen up to 42 days after infection while viral DNA was detected in semen using PCR for up to 5 months (Irons et al., 2005). Another study involving experimental intravenous inoculation with a large dose of LSDV suggested that the testis and epididymis are sites of viral persistence within bulls that exhibit prolonged viral shedding (Annandale et al., 2010). The potential for viral transmission via semen remains to be clearly demonstrated though semen that was experimentally spiked with a notably high dose of LSDV did result in viral transmission to inseminated heifers (Annandale et al., 2014). To ensure that semen is free of LSDV, Chapter 11.9 of the OIE terrestrial animal health code recommends that semen donor bulls not show clinical signs of lumpy skin disease (LSD) and reside in an LSDV-free country or zone for at least 28 days before semen collection (OIE, 2017a). Alternatively, the code recognizes the assurance of safety of bovine semen collected from bulls in countries or zones not free of LSD if (a) bulls do

not show signs of LSD, (b) bulls reside in an artificial insemination center where no case of LSD occurred during 60 days before semen collection, (c) semen to be exported was tested negative for LSDV by PCR, and either (1) bulls were vaccinated according to vaccine manufacturer’s instructions at least 60 days before first semen collection and exhibited antibodies against LSDV at least 30 days after vaccination, or (2) bulls tested negative using PCR for LSDV in blood samples at commencement of, conclusion of, and at least every 28 days during semen collection and tested seronegative for antibodies to LSDV at least every 28 days during semen collection and at 21 days after the final semen collection of the consignment (OIE, 2017a).

Bluetongue virus Controlled scientific clinical studies and field investigations focused on the excretion of bluetongue virus (BTV) in semen of bulls has significantly influenced regulatory policy regarding the movement (or lack of movement) of both live cattle and semen for many years (Thibier and Guerin, 2000; Wrathall et al., 2006). Bluetongue virus is considered the prototype of the genus Orbivirus in the family Reoviridae with the viral genome consisting of ten linear doublestranded RNA segments. Bluetongue viruses can be categorized into various serotypes, of which 27 distinct serotypes are currently proposed. This robust diversity among BTV often leads to contradictory research findings and notable consternation when clear and specific regulatory guidelines pertaining to BTV are pursued (Gu et al., 2014). Epizootic hemorrhagic disease virus is a closely related Orbivirus that cross-reacts with BTV and sometimes causes clinical disease in cattle. These viruses are transmitted between ruminants by biting midges in the Culicoides species. Cattle usually experience a subclinical BTV infection though they serve as a reservoir host due to prolonged, low level cell-associated viremias that can last up to several months (Vanbinst et al., 2010). Clinical signs in sheep are more notable than those in cattle in most circumstances and include fever, excessive salivation, nasal discharge and rare cyanosis of the tongue due to vascular compromise. Some sheep may develop respiratory distress from pulmonary edema and notably painful inflammation of the coronary bands. Depending on the strain involved, early embryonic deaths, abortions, malformed calves or lambs, temporary infertility in bulls and rams, and shedding of BTV in semen may occur (Vanbinst et al., 2010). The sporadic detection of BTV in semen of individual bulls has generally been attributed to BTV-associated red blood cells and mononuclear cells leaking into the semen through microvascular injuries due to inflammation within the male reproductive tract (Wrathall et al., 2006). However, with some BTV serotypes, the hypothesis that contamination of semen results from something other than leakage of BTVcarrying blood cells into semen is supported by: (a) the detection of concentrations of BTV in semen that equal concentrations detected in blood, (b) the shedding of BTV in semen of young and old bulls regardless of the perceived 3

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Givens propensity for inflammation of the reproductive tract and (c) the absence of detectable blood cells in semen that tested positive for BTV (Vanbinst et al., 2010). The presence of live, virulent BTV serotype 8 in extended semen from naturally infected bulls has been clearly demonstrated (Vanbinst et al., 2010). Natural infections of bulls with BTV serotype 8 have been demonstrated to precede a transient decrease in the post-thaw motility of sperm and a brief increase in the percentage of sperm exhibiting morphologic abnormalities (Muller et al., 2010). Though scientific claims were published in the late 1970s and early 1980s of transplacental BTV infections resulting in the production of immunotolerant, persistently viremic bulls, a number of attempts to confirm the findings resulted in strong refutation in 1993 of the existence of persistent BTV infection within immunotolerant cattle (Wrathall et al., 2006). More recent research has demonstrated that BTV serotype 8 can cause a transplacental infection of developing fetuses that results in the birth of virus-positive, specific antibody-negative calves (De Clercq et al., 2008). However, attempts to follow up on these five detected calves after one month demonstrated that the calves were not maintaining a detectable persistent infection (De Clercq et al., 2008). Thus, concerns regarding the persistent infection of a seronegative, post-pubertal bull that consistently or sporadically produces semen contaminated with BTV appear to lack substantial scientific support. To prevent shipment of semen containing BTV, Chapter 8.3 of the OIE terrestrial animal health code recommends that semen should be collected from bulls which show no clinical signs of bluetongue on the day of semen collection and have been – for at least 60 days before commencement of and during collection of semen – (a) kept outside a restricted zone, (b) protected against viral vectors or (c) kept during the seasonally vector-free period in a BT seasonallyfree area. Bulls may also be subjected to diagnostic tests with negative results to provide assurance of uncontaminated semen: (a) lack of detected antibodies to the BTV group at least every 60 days throughout the semen collection period and between 28 and 60 days after the final collection for this consignment, or (b) virus isolation from blood samples collected at commencement, at least every 7 days during, and at conclusion of semen collection for this consignment with negative results or (c) PCR test on blood samples collected at commencement, at least every 28 days during, and at conclusion of semen collection for this consignment with negative results (OIE, 2017a).

Foot-and-mouth disease virus Foot-and-mouth disease (FMD) is an extremely contagious disease that affects all cloven-hoofed animals. Though the mortality rate of FMD is generally low, the morbidity rate can be very high in naïve populations of cattle (Meyer et al., 2017). In acutely infected cattle, this Apthovirus in the family Picornaviridae is shed in all secretions and excretions including expired air, saliva, skin lesions, urine, feces, and semen. After experimental infection, FMDV has been

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detected in the semen of naïve bulls up to 4 days before the development of oral vesicles (Sellers et al., 1968). Experimental infection studies involving a low number of vaccinated bulls (21 total) have failed to detect FMD virus in semen of vaccinated bulls subsequent to experimental infection (Meyer et al., 2017). Infection of cows through artificial insemination with semen collected from FMDvaccinated bulls has not been reported. In some clinically and subclinically infected cattle, FMDV can be isolated from oropharyngeal fluids and/or tissues >28 days after infection (Hayer et al., 2017). This condition is referred to as persistent FMDV infection and these animals are referred to as ‘carriers’. Transmission of FMDV from carrier cattle by direct contact to naïve cattle is extremely difficult to reproduce under experimental conditions and is considered not to be epidemiologically significant (Hayer et al., 2017). Accordingly, the potential for seropositive carrier bulls to transmit FMDV via semen has been considered negligible by some authors (Meyer et al., 2017). Federal regulations require that all vaccinated donor bulls whose semen shall be imported to the United States exhibit a negative serology test for antibodies against nonstructural proteins of FMDV – vaccination does not induce such antibodies – and a negative test for virus from an esophageal–pharyngeal sample (Callis, 1996). To prevent transmission of FMDV in shipped semen, Chapter 8.8 of the OIE terrestrial animal health code recommends that semen donors (a) show no clinical signs of FMD on the day of collection, (b) were kept for at least 3 months before collection in a FMD-free country, zone, or compartment and (c) were kept in an artificial insemination center where no animals had a history of infection with FMDV (OIE, 2017a). If being shipped from areas where vaccination is practiced, bulls should additionally either be vaccinated at least twice with the last vaccination ⩾1 month but ⩽6 months before collection or test free of antibodies against FMDV not <21 days after collection of the semen (OIE, 2017a).

Schmallenberg virus Schmallenberg virus may cause stillbirths and musculoskeletal and central nervous system malformations of developing fetuses in naïve dams infected during pregnancy (Hoffmann et al., 2013). This Orthobunyavirus is transmitted by biting midges of the Culicoides genus and mosquitoes. The viremia in SBV infected cattle is very short (1 to 5 days; Hoffmann et al., 2012; OIE, 2017b) though SBV RNA has been detected – sometimes intermittently – up to almost 3 months after seroconversion (Hoffmann et al., 2013; Ponsart et al., 2014). This virus can be detected in seminal plasma early in acute infections (which may clear without serial positive semen samples) and be associated with the seminal cell fraction in serial positive samples weeks after seroconversion (Hoffmann et al., 2013). A single insemination dose of semen can contain SBV sufﬁcient to infect naïve cattle through experimental subcutaneous injection though transmission of SBV by natural breeding or artiﬁcial insemination remains to be demonstrated (Schulz et al., 2014). To declare semen free of SBV, testing of semen samples for SBV

Disease risks from bovine semen RNA using PCR is recommended unless the bull tests negative for SBV-speciﬁc antibody at least 28 days after semen production (Van Der Poel et al., 2014). Bacterial, protozoal and parasitic pathogens

Tritrichomonas foetus and Campylobacter fetus venerealis are sexually transmitted diseases that do not cause detectable disease in the bull (Peter, 1997; BonDurant, 2005). These organisms reside on the epithelium of the preputial cavity of infected bulls. The epithelial crypts of the prepuce provide a microaerophilic environment that supports replication of these microbes. Accordingly, bulls may develop a life-long infection. While the organisms are generally associated with the glans penis and proximal prepuce, semen can become contaminated during collection. Tritrichomonas foetus and Campylobacter fetus venerealis can survive cryopreservation of semen (Peter, 1997). Trichomonads have been shown to adhere to sperm causing a decrease in sperm motility, sperm agglutination, and phagocytosis (Benchimol et al., 2008). Transmission of T. foetus or C. fetus to the female can result in vaginitis, cervicitis, endometritis, infertility, delayed return to estrus, early embryonic death and rarely abortion (up to 4 months of gestation, T. foetus; 4 to 7 months of gestation, C. fetus) (Peter, 1997; BonDurant, 2005). Occasionally, postcoital pyometra can result from uterine infection. Infection of the female reproductive tract consistently leads to a notable humoral immune response that commonly clears infections within 90 days. A reliable vaccine is available for campylobacteriosis that can stimulate the prevention and elimination of infections in cows and bulls. The killed, whole cell vaccine available for T. foetus has not been demonstrated to stimulate immunity that consistently clears infections in bulls though vaccination of heifers and cows before the breeding season will signiﬁcantly improve reproductive performance in the event of venereal transmission (Edmondson et al., 2017). For natural breeding, only virgin bulls should be introduced to cattle operations to minimize concerns regarding introduction of T. foetus or C. fetus. Brucella abortus is an organism that can also localize in the reproductive tract of the bull. The cells of the genital tract contain high concentrations of erythritol which enhances the growth of this zoonotic pathogen. Infection can lead to orchitis, epididymitis, seminal vesiculitis, ampullitis, decreased libido and infertility. The organism can also be present in collected semen (Eaglesome and Garcia, 1997). Other bacterial organisms can be transmitted in semen and might be associated with infertility or transmission of the disease. Furthermore, several of the organisms are infectious following cryopreservation of semen. Leptospira spp. can be isolated from the genital tract of subclinical bulls and transmitted in semen (BonDurant, 2005). The organism can also survive cryopreservation. Histophilus somni can be isolated from the reproductive tract of normal bulls and be present in semen (Humphrey et al., 1982). While the organism is sensitive to antimicrobials, it is not known if transmission via processed semen would result in infection of susceptible

cows. Likewise, Ureaplasma diversum can be transmitted in semen and induce endometritis, salpingitis and cervicitis, but can also be isolated from unaffected animals (BonDurant, 2005). Mycobacterium avium subsp. paratuberculosis can also be present in the semen of subclinical bulls (Ayele et al., 2004). This organism is capable of surviving antibiotics and cryopreservation. In addition, Chlamydiaceae can cause infection of the reproductive tract of the bull (Teankum et al., 2007). These gram-negative intracellular pathogens can be present in semen and survive cryopreservation. Other organisms which might be transmitted via semen include Mycobacterium bovis, Coxiella burnetii and Mycoplasma mycoides ssp. mycoides (Kruszewska and TylewskaWierzbanowska, 1997; Wentink et al., 2000). Though DNA of Neospora caninum has been detected in semen, studies indicate that the possibility of venereal transmission is very low to non-existent (Ferre et al., 2008). Conclusion Based on understanding speciﬁc viral, bacterial, protozoal, and parasitic infections that may result in contamination of bovine semen, prudent and practical control measures can be effectively developed and implemented for each farm, region, state or country. While several pathogens can potentially be transmitted through cryopreserved bovine semen, following disease control recommendations provided by the World Organization for Animal Health (OIE) and CSS will ensure that the risk of pathogen transmission through semen is negligible. Acknowledgements The author has received prior research funding and honoraria from Boehringer Ingelheim Vetmedica, Zoetis, Elanco, and IDEXX. Declaration of interest None. Ethics statement None. Software and data repository resources None.

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Givens Benchimol M, de Andrade Rosa I, da Silva Fontes R and Burla Dias AJ 2008. Trichomonas adhere and phagocytose sperm cells: adhesion seems to be a prominent stage during interaction. Parasitology Research 102, 597–604.

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Bielanski A 2007. Disinfection procedures for controlling microorganisms in the semen and embryos of humans and farm animals. Theriogenology 68, 1–22.

Irons PC, Tuppurainen ES and Venter EH 2005. Excretion of lumpy skin disease virus in bull semen. Theriogenology 63, 1290–1297.

Bielanski A, Dubuc C and Hare WCD 1992. Failure to remove bovine diarrhea virus (BVDV) from bull semen by swim up and other separatory sperm techniques associated with in vitro fertilization. Reproduction in Domestic Animals 27, 303–306.

Kirkland PD, Richards SG, Rothwell JT and Stanley DF 1991. Replication of bovine viral diarrhoea virus in the bovine reproductive tract and excretion of virus in semen during acute and chronic infections. Veterinary Record 128, 587–590.

Bielanski A, Loewen KG and Hare WC 1988. Inactivation of bovine herpesvirus-1 (BHV-I) from in vitro infected bovine semen. Theriogenology 30, 649–657. BonDurant RH 2005. Venereal diseases of cattle: natural history, diagnosis, and the role of vaccines in their control. Veterinary Clinics of North America-Food Animal 21, 383–408.

Kruszewska D and Tylewska-Wierzbanowska S 1997. Isolation of Coxiella burnetii from bull semen. Research in Veterinary Science 62, 299–300. Meyer A, Zamir L, Ben Yair Gilboa A, Gelman B, Pfeiffer DU and Vergne T 2017. Quantitative assessment of the risk of release of foot-andmouth disease virus via export of bull semen from Israel. Risk Analysis 37, 2350–2359. Muller U, Kemmerling K, Straet D, Janowitz U and Sauerwein H 2010. Effects of bluetongue virus infection on sperm quality in bulls: a preliminary report. Veterinary Journal 186, 402–403. Newcomer BW, Toohey-Kurth K, Zhang Y, Brodersen BW, Marley MS, Joiner KS, Zhang Y, Galik PK, Riddell KP and Givens MD 2014. Laboratory diagnosis and transmissibility of bovine viral diarrhea virus from a bull with a persistent testicular infection. Veterinary Microbiology 170, 246–257. OIE 2017a. Terrestrial Animal Health Code. Office International des Epizooties (OIE), Paris, France. Retrieved on 15 December 2017 from http://www.oie.int/ international-standard-setting/terrestrial-code/access-online/ OIE 2017b. Technical factsheet on Schmallenberg virus (update June 2017). Retrieved on 15 December 2017 from http://www.oie.int/en/our-scientificexpertise/specific-information-and-recommendations/schmallenberg-virus/ Peter D 1997. Bovine venereal diseases. In Current therapy in large animal theriogenology (ed. RS Youngquist), pp. 355–363. W.B. Saunders Company, Philadelphia. Ponsart C, Pozzi N, Breard E, Catinot V, Viard G, Sailleau C, Viarouge C, Gouzil J, Beer M, Zientara S and Vitour D 2014. Evidence of excretion of Schmallenberg virus in bull semen. Veterinary Research 45, 37. Schulz C, Wernike K, Beer M and Hoffmann B 2014. Infectious Schmallenberg virus from bovine semen, Germany. Emerging Infectious Diseases 20, 338–340. Sellers RF, Burrows R, Mann JA and Dawe P 1968. Recovery of virus from bulls affected with foot-and-mouth disease. Veterinary Record 83, 303. Silva N, Solana A and Castro JM 1999. Evaluation of the effects of different trypsin treatments on semen quality after BHV-1 inactivation, and a comparison of the results before and after freezing, assessed by a computer image analyzer. Animal Reproduction Science 54, 227–235. Tanghe S, Vanroose G, Van Soom A, Duchateau L, Ysebaert MT, Kerkhofs P, Thiry E, van Drunen Littel-van den Hurk S, Van Oostveldt P and Nauwynck H 2005. Inhibition of bovine sperm-zona binding by bovine herpesvirus-1. Reproduction 130, 251–259. Teankum K, Pospischil A, Janett F, Brugnera E, Hoelzle LE, Hoelzle K, Weilenmann R, Zimmermann DR, Gerber A, Polkinghorne A and Borel N 2007. Prevalence of chlamydiae in semen and genital tracts of bulls, rams and bucks. Theriogenology 67, 303–310. Thibier M and Guerin B 2000. Hygienic aspects of storage and use of semen for artificial insemination. Animal Reproduction Science 62, 233–251. Vanbinst T, Vandenbussche F, Dernelle E and De Clercq K 2010. A duplex realtime RT-PCR for the detection of bluetongue virus in bovine semen. Journal of Virology Methods 169, 162–168. Van Der Maaten MJ and Miller JM 1978. Susceptibility of cattle to bovine leukemia virus infection by various routes of exposure. In Advances in comparative leukemia research (ed. P Bentvelzen, J Hilgers and DS Yohn), pp. 29–32. Elsevier, Amsterdam. Van Der Poel WH, Parlevliet JM, Verstraten ER, Kooi EA, Hakze-Van Der Honing R and Stockhofe N 2014. Schmallenberg virus detection in bovine semen after experimental infection of bulls. Epidemiology and Infection 142, 1495–1500. van Oirschot JT 1995. Bovine herpesvirus 1 in semen of bulls and the risk of transmission: a brief review. Veterinary Quarterly 17, 29–33.

Borel N, Janett F, Teankum K, Zlinszky K, Iten C and Hilbe M 2007. Testicular hypoplasia in a bull persistently infected with bovine diarrhoea virus. Journal of Comparative Pathology 137, 169–173. Callis JJ 1996. Evaluation of the presence and risk of foot and mouth disease virus by commodity in international trade. Revue scientifique et technique 15, 1075–1085. Choi KY, Monke D and Stott JL 2002. Absence of bovine leukosis virus in semen of seropositive bulls. Journal of Veterinary Diagnostic Investigation 14, 403–406. CSS 2014. CSS minimum requirements for disease control of semen produced for AI. pp. 1–15. CSS, Madison, Wisconsin. Retrieved on 15 December 2017 from https://www.naab-css.org/uploads/userfiles/files/CSSMinReq-Jan2014201607ENG.pdf. De Clercq K, De Leeuw I, Verheyden B, Vandemeulebroucke E, Vanbinst T, Herr C, Meroc E, Bertels G, Steurbaut N, Miry C, De Bleecker K, Maquet G, Bughin J, Saulmont M, Lebrun M, Sustronck B, De Deken R, Hooyberghs J, Houdart P, Raemaekers M, Mintiens K, Kerkhofs P, Goris N and Vandenbussche F 2008. Transplacental infection and apparently immunotolerance induced by a wild-type bluetongue virus serotype 8 natural infection. Transboundary and Emerging Diseases 55, 352–359. Eaglesome MD and Garcia MM 1997. Disease risks to animal health from artificial insemination with bovine semen. Revue scientifique et technique 16, 215–225. Edmondson MA, Joiner KS, Spencer JA, Riddell KP, Rodning SP, Gard JA and Givens MD 2017. Impact of a killed Tritrichomonas foetus vaccine on clearance of the organism and subsequent fertility of heifers following experimental inoculation. Theriogenology 90, 245–251. Ferre I, Serrano-Martinez E, Martinez A, Osoro K, Mateos-Sanz A, Del-Pozo I, Aduriz G, Tamargo C, Hidalgo CO and Ortega-Mora LM 2008. Effects of re-infection with Neospora caninum in bulls on parasite detection in semen and blood and immunological responses. Theriogenology 69, 905–911. Gard JA, Stringfellow DA and Givens MD 2007. Bovine viral diarrhea virus (BVDV): epidemiologic concerns relative to semen and embryos. Theriogenology 68, 434–442. Givens MD, Riddell KP, Edmondson MA, Walz PH, Gard JA, Zhang Y, Galik PK, Brodersen BW, Carson RL and Stringfellow DA 2009. Epidemiology of prolonged testicular infections with bovine viral diarrhea virus. Veterinary Microbiology 20, 42–51. Gu X, Davis RJ, Walsh SJ, Melville LF and Kirkland PD 2014. Longitudinal study of the detection of Bluetongue virus in bull semen and comparison of real-time polymerase chain reaction assays. Journal of Veterinary Diagnostic Investigation 26, 18–26. Hayer SS, Ranjan R, Biswal JK, Subramaniam S, Mohapatra JK, Sharma GK, Rout M, Dash BB, Das B, Prusty BR, Sharma AK, Stenfeldt C, Perez A, Rodriguez LL, Pattnaik B, VanderWaal K and Arzt J 2017. Quantitative characteristics of the footand-mouth disease carrier state under natural conditions in India. Transboundary and Emerging Diseases 65, 253–260. Hoffmann B, Scheuch M, Hoper D, Jungblut R, Holsteg M, Schirrmeier H, Eschbaumer M, Goller KV, Wernike K, Fischer M, Breithaupt A, Mettenleiter TC and Beer M 2012. Novel orthobunyavirus in cattle, Europe, 2011. Emerging Infectious Diseases 18, 469–472. Hoffmann B, Schulz C and Beer M 2013. First detection of Schmallenberg virus RNA in bovine semen, Germany, 2012. Veterinary Microbiology 167, 289–295.

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Disease risks from bovine semen van Oirschot JT, Rijsewijk FA, Straver PJ, Ruuls RC, Quak J, Davidse A, Westenbrink F, Gielkens AL, van Dijk JE and Moerman A 1995. Virulence and genotype of a bovine herpesvirus 1 isolate from semen of a subclinically infected bull. Veterinary Record 137, 235–239. Vogel FS, Flores EF, Weiblen R, Winkelmann ER, Moraes MP and Braganca JF 2004. Intrapreputial infection of young bulls with bovine herpesvirus type 1.2 (BHV-1.2): acute balanoposthitis, latent infection and detection of viral DNA in regional neural and non-neural tissues 50 days after experimental reactivation. Veterinary Microbiology 98, 185–196.

Weiblen R, Kreutz LC, Canabarro TF, Schuch LF and Rebelatto MC 1992. Isolation of bovine herpesvirus 1 from preputial swabs and semen of bulls with balanoposthitis. Journal of Veterinary Diagnostic Investigation 4, 341–343. Wentink GH, Frankena K, Bosch JC, Vandehoek JED and van den Berg T 2000. Prevention of disease transmission by semen in cattle. Livestock Production Science 62, 207–220. Wrathall AE, Simmons HA and Van Soom A 2006. Evaluation of risks of viral transmission to recipients of bovine embryos arising from fertilisation with virus-infected semen. Theriogenology 65, 247–274.

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Food Animal

Amelia Woolums, DVM, PhD, DACVIM, DACVM

Clinician, Department of Pathobiology and Population Medicine College of Veterinary Medicine - Mississippi State University Mississippi State, Mississippi

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Dr. Amelia Woolums, Mississippi State University

The Amazing Immune System: Review and Update

Disclosure and thanks • Dr. Woolums and collaborators have received support from: – Bayer Animal Health

Amelia R. Woolums, DVM MVSc PhD DACVIM DACVM Department of Pathobiology and Population Medicine Mississippi State University amelia.woolums@msstate.edu

Immune System: Overview • Innate immune response – Immediately and always active – Responds to a broad variety of agents

• Acquired (aka adaptive) immune response – Takes several days-weeks to be fully active – Reacts specifically to a single agent – Improves with repeated exposure: “memory”

– Boehringer Ingelheim – Merck – Merial – Phibro – Zoetis

Immune System: Overview • Innate and acquired responses are active in 2 major sites – mucosal surfaces – blood and tissue fluids • Host is thus protected from attack on any front

– Target of vaccination

Innate immune system: components • Physical or chemical barriers – Skin, mucociliary elevator, gastric pH, urine flow

• Soluble factors – in serum, secretions, excretions, tissue fluids

• Cellular factors – granulocytes, macrophages, natural killer cells, gamma delta T cells, epithelial cells

• Mechanisms important in the initial response to infection are also involved in the response to non-infectious tissue injury – trauma – burns or frostbite – bites

• All induce inflammation • Inflammation activates the immune response

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Dr. Amelia Woolums, Mississippi State University

Infection

Tissue injury

PAMPs

PAMPs and PRRs

DAMPs (“alarmins”) Sentinel cells displaying pathogen recognition receptors cytokines, vasoactive molecules

Influx of innate immune cells, vascular change associated with inflammation

• PAMPs: pathogen associated molecular patterns – Highly conserved molecules found in many different microorganisms – Host response evolved to recognize these

Infection or injured tissue is REMOVED OR acquired immune response is activated in continued effort to remove infection

Important PAMPs • Peptidoglycan and lipoteichoic acid – Gram positive bacteria (Staph., Strep., and others) • Lipopolysaccharide – Gram negative bacteria (E. coli, Salmonella, and others) • Glycolipids – acid-fast bacteria (mycobacteria: Johne’s disease, TB) • Mannan-rich carbohydrates – fungi (Aspergillus and others) • Unmethylated CpG nucleotide motifs – bacteria and viruses • dsRNA – viruses

• Intracellular DAMPs – High mobility group box protein-1 (HMGB1)

• relatively few molecules can initiate immunity to the limitless microbial world

Some important DAMPs • DAMPs are components of host tissues • Extracellular DAMPs – Extracellular matrix components • hyaluronic acid • fibronectin • collagen-derived peptides • elastin

• Release of small and/or soluble fragments during tissue injury allows PRR activation

• Sentinel cells in tissues are the first cells to see PAMPs or DAMPs

• Associated with DNA in normal cells: ensures proper folding • Triggers inflammation when released from damaged cells

– dendritic cells

– If DNA associated: anti-DNA response can occur

– macrophages

• Can be secreted by macrophages

– Unmethylated CpG DNA from mitochondria – Adenosine • In cAMP, ATP, nucleic acids

– Uric acid • Breakdown product of purines (e.g. adenine, guanine)

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– mast cells – epithelial cells – fibroblasts

These cells can also be called into regions of inflammation

Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

• Given stimuli that lead to “classical activation”, macrophages become M1 macrophages

Macrophages • Identify and kill pathogens via many PRRs and other surface receptors – phagocytosis

– Phagocytosis – Microbial killing – Proinflammatory cytokine production

– secrete antimicrobial products • Given stimuli that lead to “alternative activation”, macrophages become M2 macrophages – Suppression of inflammation

• Produce proinflammatory cytokines – IL-1, TNF-a, and IL-6

– Promotion of blood vessel formation

– activate inflammation

– Promotion of tissue remodeling and repair

• kick off the immune response

Mast Cells “Accumulated evidence indicates that macrophages are functionally plastic cells with the potential to alter their activities progressively and reversibly in response to changes in the tissue environment.” Sang et al., 2011

• Originate from myeloid precursors in bone marrow • Migrate to tissues – Mucosal mast cells: under mucosal surfaces – Connective tissue mast cells: in skin, peritoneal cavity • Granules contain enzymes and vasoactive mediators • Degranulate when surface IgE molecules crosslinked antigen binding – Key mediator of allergy and anaphylaxis

Pathogen recognition receptors (PRR) • It is now recognized that mast cells can respond to PAMPs and DAMPs via PRRs – Help initiate early inflammatory response to many stimuli – Granules are released “piecemeal” • Provides a more titrated response than when antigen binds surface IgE

• Sentinel cells activate the inflammatory/immune response when their PRR bind PAMPs or DAMPs • PRR are found – On cell surface – Inside endosomes inside the cell – In cell cytoplasm

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Dr. Amelia Woolums, Mississippi State University

Sites where cellular pathogen recognition receptors (PRR) can bind to PAMPs or DAMPs

TLR-4 TLR-5

On the cell surface

TLR-1 TLR-2

• Binding of PRR by a PAMP or DAMP initiates a signal transduction sequence in the cell

CLR

TLR-6 TLR-2

Within endosomes inside of cell

TLR-3

• This will cause the cell to produce cytokines that will in turn activate the inflammatory/immune response

TLR-7

TLR-9 RIG-I MDA5

NLR

• The mixture of cytokines produced will determine the kind of immune response activated

Within the cytoplasm

Sentinel cell

Consequences of PAMP binding to PRR Example: LPS binding to TLR-4

Lipo

poly

TLR-4

ch sac e S) (LP

LPS TL

arid

• Consequence of TLR binding by PAMP

R -4

– Initiation of signal transduction sequence – Expression of genes for

D88 MY

• cytokines • other antimicrobial molecules

TRIF

MKK

IRAK

Macrophage

MAPK

NF-κB

IRF3

– Response appropriate for defense against the initiating microbe

IL-1β

A. Woolums

TNF-α

IL-6

IFN-β

Cytokines • All cells influence other cells by release of cytokines • Cytokines... – Activate the immune response – Direct specific types of responses • Anti-viral, anti-bacterial, anti-parasitic

– Contribute to inflammation and sometimes death • “Septic shock”

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• Different TLRs trigger different combinations of gene expression

So… why does this matter??

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192

193

194

195

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Dr. Amelia Woolums, Mississippi State University

Immunity in Calves and Stockers: What’s the Latest?

Disclosure and thanks • Dr. Woolums and collaborators have received support from: – Bayer Animal Health – Boehringer Ingelheim – Merck – Merial

Amelia R. Woolums, DVM MVSc PhD DACVIM DACVM Department of Pathobiology and Population Medicine Mississippi State University amelia.woolums@msstate.edu

Collaborators, stocker vaccination study • Mississippi State University – John Blanton – Bill Epperson – Brandi Karisch – David R. Smith – Students • Courtney Griffin • Tucker Wagner

• University of Georgia – Ray Kaplan

– Phibro – Zoetis

Immune Development: Prenatal Calf • Immune system begins developing before calf is born – Thymus (T cell development) evident at 40 days gestation – Response to some viruses possible at 70 days gestation – By third trimester, can respond to many different infections • At birth, see serum antibody titers elevated before colostrum intake

Immune Development, Neonatal Calf • At birth, calf has no antibody in serum – Unless infected before birth

• Other issues – Serum complement levels lower than adults – Cell functions lower than adults

• Immune response of neonatal calf is functional, but naïve and immature • Colostrum is a solution to this problem

• neutrophils • macrophages • antigen presenting cells • T and B cells

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Colostrum

• Antibody molecules in colostrum absorbed by calf s intestine intact • Absorption only continues for first 24 - 36 hours – Time shortens once calf nurses ( gut closure )

• Colostral antibodies also provide protection against intestinal infection – Before absorption – When secreted back from blood into intestine

– Feeding something before colostrum can impair absorption of colostral antibodies

• Important for controlling infectious causes of calf diarrhea

• Colostral antibodies persist in serum for 2-6 months

Percent of U.S. dairy heifers with failure of passive transfer

Percent of operations that routinely monitor serum total protein as a measure of passive transfer status of heifer calves

NAHMS 2007

NAHMS, 2014

19%

Failure of passive antibody transfer in beef calves

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Study

Cutoff

Perino et al., 1995

Serum IgG < 800 mg/dl

Percent FPT 23%

Filteau et al., 2003

Serum IgG1 < 1000 mg/dl

19%

Dewell et al., 2006

Serum IgG1 < 800 mg/dl

14%

Waldner and Rosengren, 2009

Serum IgG < 800 mg/dl

• Before anything else, excellent passive transfer is required to establish the basis for strong calf immunity • There is still room for improvement in colostrum management on some operations

Dr. Amelia Woolums, Mississippi State University

Missouri VMA 127th Annual Convention January 26, 2019

Importance of Cells in Colostrum

Maternal Cells in Colostrum • Maternal cells in colostrum migrate across calf intestine – Found in calf tissues in first few days after birth – Associated with changes in immune development in neonatal calf

• Calves receiving colostrum containing maternal cells – Developed ability to activate an immune response sooner Reber et al, 2005

– Had measurable responses to bovine pathogens at 1 day of life Donovan et al, 2007

....as compared to calves receiving colostrum without cells

• Other recent studies confirmed that maternal cells in colostrum induce measurable effects in calves in the first few days of life – Langel et al., 2015 – Meganck et al., 2016 Donovan et al, 2007

• Frozen colostrum does not contain whole cells – Need fresh colostrum to give cells

• What if you have high antibody titer frozen colostrum, or low antibody titer fresh? – Need more research to confirm longterm benefits of maternal cells – At this time, recommend high antibody titer frozen – Stay tuned for more information

Development of Acquired Immune Response • Calf can respond to infection in first few days of life – Weaker and less effective than adult response – Very high levels of colostral antibody will diminish responses specifically • No colostral antibody: response not diminished Nonnecke et al., 2012

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Dr. Amelia Woolums, Mississippi State University

Factors Affecting Stocker Immunity • HOWEVER: vaccination of calves with maternal antibodies can sometimes be effective – More in the next hour

Duff and Galyean, 2007

Stocker Immunity • Defining “immunity” – In vitro measures: resting or stimulated • innate mechanisms • antibody production • cell mediated immune responses

– Resistance to disease

• Which is most informative? • Which do we care about?

• Negative effects of stress are not always mediated by cortisol

Impact of stress on immunity • Stress: “Psychologically perturbing condition occurring in response to adverse external influences capable of affecting physical health.” Aich, Potter, and Griebel, 2009

• Social or psychological stress increases rate and severity of respiratory infections in humans – Social support can overcome effects of mild but not severe stress

Antibody titers to BVDV2 in calves vaccinated the first time at weaning (black bars) or 3 weeks after weaning (hatched bars)

• Presumably stressful events don’t always lead to cortisol elevation • Endogenous glucocorticoids are more immunomodulatory that immunosuppressive – Can induce a TH2-type bias in immune response • This may suppress cell-mediated immunity

n = approx 500 per group

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Downey et al., 2013

Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

Neutrophil influx into lung lavage fluid of calves after abrupt weaning and transport (stress), followed by LPS infusion into left lung at 12 hours after transport calves weaned, transported, and fasted LPS instilled (or not) into lung

Changes in immune proteins in BAL fluid of stressed vs nonstressed calves Stressed Not stressed

Stressed Not stressed

*** Significantly different, p < 0.001 Both L (+) and R (-) lungs were lavaged 24 hours after LPS infusion into L lung at 12 hours

Mitchell et al., 2008

Stress and health, summary

Significant differences in 11 of 372 proteins at 12 hours vs 0 hours

Mitchell et al., 2008

Response of high risk stockers to vaccination

• The impact of “stress” depends on how you define stress • Stressful events don’t always make immune response worse – Depends on severity and duration of stress • The negative effects of stress may not be measurable until disease challenge occurs

• When we give a vaccine, we give a version of a virus or bacteria that should induce an immune response as if the animal had a natural infection, but which shouldn’t make the animal sick

• If the animal’s immune system recognizes the agent in the vaccine and responds properly, the animal will have immunity to that agent

• This is vaccination

• This is immunization

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Antibody titers in lightweight calves at arrival Proportion of BRD cases/controls seronegative at arrival

Martin et al., 1989

Proportion of calves seronegative at arrival

• There are many reasons that vaccination may not lead to immunization

Fulton et al., 2000

Proportion of calves seronegative to IBRV at arrival: 92% Richeson et al., 2008

Antibody titers in preconditioned calves at arrival Morbidity 75%

Mean titers in groups of calves from each of 24 ranches

So just vaccinate them at arrival, right?

Calves were vaccinated with various protocols on ranch of origin prior to entering retained ownership program

78% 60%

Fulton et al., 2002

• In a small trial comparing • Administration of respiratory vaccines within 2 weeks of feedlot arrival was associated with increased mortality Martin et al., 1982

– No vaccination – MLV IM 4-way on d. 7 – MLV IN 2-way on arrival, then MLV IM 4-way on d. 7 – MLV IM 4-way on arrival and d. 7 • Calves from AR order buyer • 4 pens/treatment, 8-9 cattle/pen • For 28 day receiving period – No difference ADG, DMI, or morbidity (no mortality) – F/G increased for vaccinated calves (p < 0.10) Duff et al., 2000

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Dr. Amelia Woolums, Mississippi State University

• Another study

• Health and performance followed

– 460 lb bulls and steers • n = 15 per pen 12 pens per treatment • half received in September, half received in January

– pens allocated to receive • arrival MLV 5-way (BoviShield Gold 5) • delayed MLV 5-way (on d. 14)

– 42 day receiving period – grazing period • 98 days long for fall group • 62 days long for spring group

• no MLV 5-way

– all vac pens: boosted 14 days after vac – all pens: 8-way clostridial, moxidectin at arrival – bulls banded at arrival • allocated evenly to all treatment groups

Richeson et al., 2015

Performance of cattle receiving arrival MLV 5-way vac, delayed vac, or no vac

Increased ADG from d 0 to 14, DMLV > AMLV (p < 0.01)

Health of cattle receiving arrival MLV 5-way vac, delayed vac, or no vac

Tendency toward increased relapse rate, NO VAC > VAC (p = 0.08)

Increased ADG during grazing phase, DMLV > AMLV (p = 0.03) Richeson et al., 2015

Richeson et al., 2015

Arrival vs Delayed vac: High risk heifer study

• Delayed 5-way MLV

• Benefit of arrival vs delayed MLV 5-way – Vaccinated on d. 0 or d. 30 (Pyramid 5) – Also tested effect of DNA immunostimulant

• 60 pens containing 5,179 high risk heifers • On d. 0 all heifers received – M. haemolytica toxoid – metaphylaxis (tilmicosin) – moxidectin + oxfendazole – prostaglandin if < 90 days pregnant, excluded if >

– Decreased percent of cattle treated twice for BRD (P < 0.05) – Effect persisted through closeout

• Arrival 5-way MLV – Tended to increase • finished body weight (P = 0.08) • hot carcass weight (P = 0.07)

Rogers et al., 2016

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Dr. Amelia Woolums, Mississippi State University

• Arrival vs delayed vac, other work:

Mean BRD retreatment risk at (+/- SEM) at closeout

– Few differences in health and performance outcomes for cattle given MLV 5-way at arrival vs d. 14 • Study 1: ADG better for delayed vac – No difference for health outcomes • Study 2: First BRD treatment earlier for arrival vac: – No difference for performance outcomes – Humoral immune responses better for delayed vac in one study but not the other Richeson et al., 2008 and 2009 Rogers et al., 2016

Summary: stocker vaccination (so far)

• MLV 5-way vac vs no vac – Trend: increased feed efficiency – Trend: decreased relapse rate

• Lack of marked impact on BRD morbidity and mortality during backgrounding

Duff 2000 Richeson 2015

• Benefits may be greater in the feedlot?

• Delayed vac vs arrival – Increased ADG

– Need to look into this

Richeson 2008 and 2015

– Decreased percent second treatments – Trend: decreased finish weight and HCW

Rogers 2016

– Increased days to first treatment

Richeson 2009

Rogers 2016

Vaccination and deworming at arrival: Mississippi State University trials

• 2 x 2 study design – VAC or NO VAC: MLV-5 way (Express 5) + clostridial (Vision 7) – DWM or NO DWM: levamisole + fenbendazole – 4 cattle per pen, 5 pens per group – Bulls and steers • bulls surgically castrated

• Objective: evaluate effect of on-arrival vaccination and deworming on health, performance, and immune response to vaccination • • • •

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– All cattle BVDV PI tested (none found) All cattle vaccinated on d. 56 Health and weight gain followed over 85 days SN titers to BHV-1 and BVDV1 measured Power calculation: ID difference in morbidity at P = 0.10

Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

FEC for Trial 1 stockers dewormed or not dewormed on d. 0

• Three trials completed: • Trial 1 (spring 2015): – BRD morbidity: 46%

BRD mortality: 16%

– vaccinated cattle more likely to • be treated for BRD • die due to BRD – deworming: no effect on health or growth Griffin et al., Bov Pract 52:26-33, 2018 FEC presented are model-adjusted, natural log transformed. Bars = 1 SE Values with different superscripts are significantly different (a = 0.05)

BHV-1 SN titers for Trial 1 stockers vaccinated or not vaccinated on d. 0. All cattle were vaccinated on d. 56

SN titers are model-adjusted. Bars = 1 standard error. Values with different superscripts are significantly different (a = 0.05)

Griffin et al., 2018

• For trial 1 cattle: – In spite of • high risk status • poor clinical response to arrival vaccination… …cattle were able to mount a humoral immune response to vaccination on arrival • Calves vac at arrival had significantly higher titers to BHV-1 from d. 14 to d. 85 • Calves vac at arrival had significantly higher titers to BVDV1 at d. 28 and 56 but not d. 85 • Titers in no vac calves d. 0 – 56 suggested no BHV-1 but maybe BVDV1 was circulating among cattle

Griffin et al., 2018

BVDV-1 SN titers for Trial 1 stockers vaccinated or not vaccinated on d. 0. All cattle were vaccinated on d. 56

SN titers are model-adjusted. Bars = 1 standard error. Values with different superscripts are significantly different (a = 0.05)

Griffin et al., 2018

• Why would vaccination make BRD worse? – BRD due to pathogens not in vaccine? • Should have made BRD the SAME in both groups – Vaccination induced excessive inflammation? • Impact of MLV 5-way vs clostridial vaccine? • Impact of VERY high risk cattle – many bulls, which were castrated at arrival • BRD vac at arrival also made disease worse in Canadian research from early 1980’s Martin et al., 1982

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Stocker vaccination, knowledge gap • We know essentially nothing about innate or cell-mediated immunity in stocker cattle vaccination – We’re trying to work on that

• Does vaccination during the stocker phase improve health and/or performance in the feedlot phase?

Missouri VMA 127th Annual Convention January 26, 2019

Resistance to disease and performance: effect of castration • For bulls castrated at arrival, significant effects: • Morbidity and F/G higher, ADG lower

Zinn, 1987

• Morbidity and mortality higher, ADG lower

Brazle, 1994

• Morbidity and mortality higher, ADG lower Daniels et al., 2000 • Morbidity higher, ADG lower

Pinchak et al., 2004

• Morbidity, mortality, retreatments, and cost of treatment Burciaga-Robles et al., 2006 higher, ADG lower

Stocker immunity and health: take home messages • Creative thinking is needed to address bull calves in the stocker industry

• Many forces are likely to negatively impact stocker immunity… …but for many situations, details are lacking – Stocker groups are highly variable • What’s true for one group may not be true for others • We need data to confirm our suspicions and biases!

Stocker immunity and health: take home messages • Multiple studies show high risk stockers are often seronegative to common viral pathogens • Backgrounding vaccination may improve performance and health • Vaccination of sick cattle may be worse than no vaccination • We need more information to guide best use of vaccines to support stocker health

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Acknowledgements • Funding for study to assess response to vaccination and deworming – Mississippi State University • Department of Pathobiology and Population Medicine • Department of Animal and Dairy Sciences • MAFES Revolving Livestock Fund – University of Georgia • Kaplan lab

Dr. Amelia Woolums, Mississippi State University

Keys to Effective Vaccination of Calves

Missouri VMA 127th Annual Convention January 26, 2019

Disclosure and thanks • Dr. Woolums and collaborators have received support from:

Amelia R. Woolums, DVM MVSc PhD DACVIM DACVM Mississippi State University Starkville, Mississippi, U.S.A. amelia.woolums@msstate.edu

Vaccinating Calves: Questions

– Bayer Animal Health – Boehringer Ingelheim – Merck – Merial – Phibro – Zoetis

Response of calf lymphocytes to mitogenic (nonspecific) stimulation in first week of life

• Can immunity of calves be improved by vaccination? • How early can you vaccinate calves effectively? • What about maternal antibody interference?

• Calves vaccinated at 8 hours old were protected against Mycobacterium bovis challenge 15 weeks later

Data from Kehrli, in Cortese 2009

Immune Development, Neonatal Calf

Buddle et al., 2003

• Colostrum-deprived calves exposed to coronavirus at 1 day of age were protected against challenge at 3 weeks

• Immune response of neonatal calf is functional, but naïve and immature

Heckert et al., 1991

• Calves vaccinated with ovalbumin at 2 days of age: antibody at 4 weeks • Calves vaccinated with PPD at 2 days of age: skin test Nonnecke et al., 2012 positive at 7 weeks

• Colostrum is a solution to this problem

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Missouri VMA 127th Annual Convention January 26, 2019

Why We Vaccinate

â&#x20AC;˘ Before anything else, excellent passive transfer from colostrum is required to establish the basis for strong calf immunity

Total Ig IgG

Antibody titer

Priming vaccine

Vaccines Available For Calves in U.S. Diarrhea E. coli rotavirus coronavirus Salmonella Clostridium

Respiratory disease BHV-1 (IBR)

Reproductive disease BHV-1 (IBR) BVDV BRSV Leptospira PI3V Campylobacter BVDV Brucella Mannheimia haemolytica Pasteurella multocida Miscellaneous Histophilus somni Clostridium 7-way Mycoplasma bovis (blackleg etc.) rabies

Antibody titer

Anamnestic (memory) response

IgM

Booster vaccine

Vaccination of calves that have maternal antibody â&#x20AC;˘ Vaccination of calves with maternal antibody historically considered ineffective

No response

Antibody titer

Primary response

Time

Vaccination without maternal antibody

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Time

Vaccination with maternal antibody

Dr. Amelia Woolums, Mississippi State University

• In spite of this thinking, research studies indicate calves CAN respond to vaccination even when they have maternal antibody – Anamnestic response when maternal antibodies gone – Measures of T cell responsiveness in absence of seroconversion

– Protection against later challenge

• Calves vaccinated at 2-3 months seroconverted to BVDV – IBRV titers continued to fall

Missouri VMA 127th Annual Convention January 26, 2019

Vaccination of calves with maternal antibody • 2-3 month old beef calves – Vaccinated with MLV IBRV + BVDV • IBRV SN titers 1:19 • BVDV SN titers 1:35

• Control calves not vaccinated • Both groups vaccinated again at 6-7 m.o. Menanteau-Horta et al, 1985

Antibody titer

• At vaccination at 6-7 months, vaccinated calves seroconverted rapidly to IBRV – Significantly higher titers than calves not vaccinated at 2-3 months

2-3 months

6-7 months

Vaccination of calves with maternal antibody can prime for memory response when maternal antibodies are gone

Calf vaccination and antibody responses— inactivated vaccines • 2 – 3 month old beef calves IBRV SN titers:

<1:2 – 1:128

BVDV 1 SN titers:

1:20 - 1:1920

BVDV 2 SN titers:

1:7.5 - 1:1280

– Inactivated IBRV/BVDV/PI3/BRSV • Vira Shield® 5

• At 6-7 months of age, calves in Vira-Shield group had significantly higher titers to IBRV, BVDV 1, and BVDV 2 than control calves

• Administration of an inactivated vaccine caused antibodies to stay higher – Not all vaccines were equal – Boosting may be important

• ELITE® 4 • Triangle® 4

– Control group, no vaccine – Boosted 1 month later

Kaeberle et al, 1998

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Missouri VMA 127th Annual Convention January 26, 2019

Vaccination of calves with maternal antibody—effect of age Antibody titer

• Dairy calves vaccinated with M. haemolytica vaccine (Presponse®) – 2 and 4 weeks old – 6 and 8 weeks old – Control group not vaccinated Time

• No difference in titers at 2 weeks of age Hodgins and Shewen, 1998

Vaccination of calves with maternal antibody can cause antibody titers to stay higher

• At 10 weeks of age, leukotoxin neutralizing titers significantly higher in calves vaccinated at 6 and 8 weeks – Not significantly higher in calves vaccinated at 2 and 4 weeks

• Magnitude of titer and age may impact efficacy of vaccination in young calves with maternal antibody

Vaccination of calves with maternal antibody and T cell responses • Beef calves vaccinated at 10 days old – MLV/inactivated 4-way (CattleMaster 4®) – Control group not vaccinated • At 22 days old – No difference antibody titers – Significantly higher lymphocyte responses to IBRV and BRSV in vaccinates Ellis et al, 1996

Summary • Vaccination stimulated specific T cells, even though no apparent effect on antibody production

• Vaccination of calves that have maternal antibody can: – Prime for a memory response after maternal antibodies are gone – Keep calf serum antibodies higher longer – Stimulate T cell responses

• Not as reliable in calves < 1 month old

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Vaccination of calves that have maternal antibody: resistance to disease • Increased resistance to disease: best measure of value of vaccination

Missouri VMA 127th Annual Convention January 26, 2019

Vaccination and resistance to disease: one example • 4 to 6 week old Holsteins – SN titers 1:4 – 1:64 – “Vaccinated” IN once with MLV (hi pass) BRSV

• Effect has been measured in response to – Experimental challenge – Naturally-occurring disease

– Challenged on d. 30 with virulent BRSV – Clinical signs evaluated for 7 days – BRSV-specific IFN-g production in several sites evaluated Woolums et al, 2004

• Duration of protection following intranasal vaccination may not be long • This may be particularly true for BRSV

Disease in calves challenged with BRSV after IN vaccination IFOMA at 3 – 8 days of age

Rectal temperatures measured after BHV-1 challenge Calves vac IN at 3-8 days of age A and B: no maternal antibody to BHV-1 C: maternal antibody to BHV-1 Challenged at 1 month after vac (A) 6 months after vac (B) 3 months after vac (C) Mahan et al., 2016

7 weeks post vac

9 weeks post vac

14 weeks post vac Ellis et al., 2013

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Missouri VMA 127th Annual Convention January 26, 2019

Vaccination of Calves: Field Trials

BHV-1 shedding after BHV-1 challenge

• Most relevant measure of vaccine efficacy • Expensive and logisitically challenging to conduct

Mahan et al., 2016

Field Trial Example #1 • 27 dairy herds with calf respiratory disease in previous year – Evidence of BRSV infection in previous year in 20

• Calves had low serum titers to BRSV at vaccination (78% had no BRSV antibodies) • Calves examined by vet weekly from October to January • BRSV infection occurred in – 6 of 8 nonvaccinated herds

• 9 herds: calves vaccinated with MLV BRSV twice at 4 to 5 week interval • 8 herds: calves not vaccinated • 10 herds: half calves vaccinated, half not

– 9 of 10 partly vaccinated herds

•

Signs of respiratory disease seen in

• Calves 2-10 months of age at vaccination

– 4 of 8 nonvaccinated herds

• Vaccinated in August

– 1 of 9 completely vaccinated herds

Verhoeff et al., 1984

Field Trial #1, Key Points • MLV BRSV vaccination associated with decreased disease in vaccinated herds • INFECTION with BRSV was decreased only when all calves were vaccinated – Vaccinating half of calves decreased disease but not infection • Calves got 2 doses of vaccine – Can’t say if 1 dose would have same effect

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– 2 of 9 completely vaccinated herds

– 1 of 10 partly vaccinated herds

Field Trial Example #2 • Weaned beef calves destined for feedlots • Single ranch of origin – Shipped immediately at weaning OR – Kept on farm 45 d., no vac OR – Kept on farm 45 d. and MLV viral vac (Titanium 5) and M. haemolytica vac (Presponse) • Vac calves boosted 2 weeks later • Calves not vac at farm were vac and boosted at feedlot Step et al, 2008

Dr. Amelia Woolums, Mississippi State University

• Calves kept on ranch 45 days before shipment had significantly lower feedlot respiratory morbidity in first 42 days – 6% for weaned 45 d. – 10% for weaned 45 d. and vaccinated – 35% for shipped immediately • No significant difference if calves vaccinated on ranch • Health costs (but not total costs) higher for calves shipped immediately

Missouri VMA 127th Annual Convention January 26, 2019

Field Trial #2, Key Points • Vaccination component of a preconditioning program was not related to improved health during receiving period • Early weaning before shipment did improve health during receiving period

– No difference for vac vs nonvac groups

Field Trial, Example #3 • 468 calves from 3 dairies in Ontario – Within each herd, calves randomly assigned to receive • IN MLV 3-way vac (Inforce) at 3 – 6 d of age and again at 6 weeks (n = 215) • SC MLV 5-way vac (Bovishield Gold 5) at 6 weeks (n = 211) • Control: saline IN both IN and SC at 3 – 6 d and 6 weeks (n = 42)

• Treatment groups housed in different areas to prevent transfer of vaccine between groups • Calves examined by a veterinarian twice a week for 12 wk – Wisconsin respiratory score – Thoracic ultrasound

• 54% of calves had respiratory score ≥ 4 at least once – Rate of BRD for each group

• IN vac: 53% • SC vac: 59% • Control: 33% – controls less likely to have BRD than IN or SC (P < 0.05) – no difference between vac groups (P > 0.05)

• 54% of calves had lung consolidation on ultrasound – Agreement between clinical signs and US only fair: k = 0.38

Ollivett et al., 2018

• Accounting for herd, dystocia, and rib fractures: • Odds of consolidation: – For SC: 1.6 that of IN (P = 0.03) 0.38 times Control (P = 0.03) – For IN 0.23 times Control (P = 0.03)

• In summary – Vaccination had no effect on clinical signs of disease, but decreased risk of lung consolidation • IN vac 2x decreased lung consolidation more than SC vac 1x

Field Trial #3, Key Points • Ultrasound was needed to identify effect of vaccination – Also needed to control for farm, dystocia, rib fractures • Calves got 2 doses of IN vac vs 1 dose of SC • Can’t separate effect of vaccination from location • Relatively high rate of FPT (TP < 5.2 mg/dL) – IN: 48%

SC: 31%

Control: 21%

– BUT analysis did not reveal effect of FPT on response to vaccination

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Dr. Amelia Woolums, Mississippi State University

Case for Discussion • 65 head cow-calf operation

Case for Discussion • Herd evaluation

• BRD in nursing calves 3 to 4 months old

– Dam body condition and nutrition acceptable

• 30% of calves have signs, 2 have died

– Calving season lasts 5 months

– Necropsy of 1 calf: BRSV and Mannheimia • Three pregnant heifers purchased from neighbor 2 months ago

• Plan to help limit disease in calves now: – Consider • treat all calves with long-acting antibiotic OR • increase surveillance and treat calves with signs of disease

– Vaccination in face of outbreak? • Often done for IBR/PI3 (especially intranasal) • May be harmful with BRSV… ….But often done with apparently no problems

• Plan for vaccinating calves: – Time vaccine to occur a month before expected disease onset • At 2 months of age in this herd – MLV may be best • Must be safe for use with pregnant cows • If killed, ask rep for data showing efficacy in animals with antibody – Consider Mannheimia/Pasteurella vaccine, too – TWO doses ideal • At 6 weeks and 10 weeks of age (or earlier?)

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– Cows not vaccinated or dewormed regularly • vaccinated once 2 years ago with killed 5-way – Calves not handled until weaning

• Plan to prevent this problem in future: – Improve maternal antibody to respiratory viruses in calves • Get cows on annual program of 5-way vaccination – Try to boost late in pregnancy? – Shorten calving season – Alternatively, group cows with calves no more than 60 day age range – Consider vaccinating calves

Calf vaccination: take home messages: • Young calves can respond to immune stimulation – As early as 1 day of life – Reliability of response inversely correlated with age • Especially in calves with good passive transfer

• Adult immune responses present by 5 – 8 months

Dr. Amelia Woolums, Mississippi State University

Calf vaccination: take home messages: • Passive antibody blocks immune responses sometimes but not always – Blocking greatest in first month of life • Intranasal may be better than injectable in first month – Calves 2 – 3 months old: blocking not much problem

Missouri VMA 127th Annual Convention January 26, 2019

Calf vaccination: take home messages: • If vaccinating in first 6 months of life, 2 doses advised – 1 – 2 months between doses – Try to time second dose 1 month before expected challenge

– Really need more research confirming effect on disease

Calf vaccination: take home messages: • BRD vaccines must show efficacy in challenge studies to be licensed – But challenge studies are relatively artificial

• Most available clinical trial evidence supports vaccines for: – Mannheimia haemolytica – BRSV

• We need more clinical trials to know how BRD vaccines work in “real life”

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Risk Factors for Bovine Respiratory Disease in Preweaning Beef Calves

Disclosure and thanks • Calf BRD Case-Control Study – Zoetis

• Other support – Bayer Animal Health – Boehringer Ingelheim Amelia R. Woolums, DVM MVSc PhD DACVIM DACVM Department of Pathobiology and Population Medicine Mississippi State University amelia.woolums@msstate.edu

Collaborators, Case-Control Study Mississippi State University

University of Georgia

David R. Smith

Roy Berghaus

South Dakota State University

Kansas State University

Russ Daly

Brad White

North Dakota State University

University of Nebraska, Lincoln

Jerry Stokka

Dale Grotelueschen

– Merck – Merial – Phibro

Calf BRD: Incidence and Impact • Leading cause of preweaning death in calves 3 weeks of age and older • 16% of deaths of calves born alive are due to BRD NAHMS, 2010

Student interviewers: Tucker Avra, Matt Jenerette, Ali Terrell

Calf BRD: Incidence and Impact • BRD can be a problem for an important proportion of herds – 20% of U.S producers indicated that nursing calf BRD had been a problem in previous 12 months CHAPA, 1993

• Nursing calf BRD in a large U.S. research herd (MARC): – From 110,412 calves over 20 years: • Annual incidence: 3% – 24% – Mean incidence: 11% • Annual mortality: 7% - 17% – Mean mortality: 13% Muggli-Cockett et al., 1992; Snowder et al., 2005

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Annual incidence of preweaning calf BRD over 20 years in a large U.S. research herd

Snowder et al., 2005

Missouri VMA 127th Annual Convention January 26, 2019

Number of calves diagnosed with respiratory disease by age over 20 years in a large U.S. research herd

Snowder et al., 2005

Calf BRD: Incidence and Impact – Affected calves weighed 17 pounds less at weaning than unaffected calves – In some years, the incidence of preweaning BRD was higher than postweaning BRD

• From a survey of 332 producers in Canada: – Mean mortality due to calf BRD • 13% in herds with < 40 cows • 18% in herds with ³ 40 cows Dutil et al., 1999

• Recent report from analysis of NAHMS data – 443 U.S. herds in 24 states

Distribution of preweaning calf BRD rate in 443 U.S. herds

• states represented 80% of the U.S. cow-calf herds – Mean percent of preweaning calves with respiratory disease: 3% +/- 7% – Mean BRDC rate: 1.5 cases/10,000 calf-days • Range: 0 – 75 cases/10,000 calf-days • SO: wide range in rate of calf BRD among herds Hanzlicek et al., 2013

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Hanzlicek et al., 2013

Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

Calf BRD: Incidence and Impact Summary • Approximately 20% of cow-calf herds see calves with preweaning BRD • Among affected herds, the proportion of calves affected varies widely • In a given herd, the proportion affected varies across years • Preweaning mortality attributed to BRD is approximately 15% • Costs associated with treatment and production loss not well estimated

Herd level risk factors

• But WHY would nursing calves develop pneumonia??

Mail survey of producers

• From analysis of NAHMS data: • Incidence of nursing calf BRD was increased with – Importing weaned steers – Cattle from 2 or 3 breed crosses or composite (vs purebred) – Considering operation the primary source of income (vs not) – Feeding antibiotics to calves to prevent nursing calf BRD – Herds that had visitors (tho not linear) Hanzlicek et al., 2013

Mail survey of producers • Factors associated with seeing any calf BRD – Herd size (vs herds with 1 – 49 cows) • Herds with 100 – 199 cows: OR = 4.1 • Herds with ³ 200 cows: OR = 5.0 – Diarrhea in calves: OR = 8.4

• Survey of 463 cow-calf producers in 6 U.S. states – East: GA, FL, WV – Plains: IA, KS, NE • 21% of operations reported seeing calves with BRD – Of these: • 89% reported treating at least 1 calf for BRD • 46% reported at least 1 calf death attributed to BRD Woolums et al., 2013

• Factors associated with increased proportion of calves treated for BRD – Bringing in calves (orphan or grafted) from outside sources • Proportion treated 2.6 times higher – More than 50% of calves born between January and April • Proportion treated 1.6 times higher – Giving nursing calves creep feed

– Treating at least 1 cow for BRD: OR = 4.1 – Calving season ≥ 3 months: OR = 1.4 Woolums et al., 2013

• Proportion treated 1.7 times higher – Using a heat synchronization program • Proportion treated 1.6 times higher

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Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

• Note that Hanzlicek et al. found different risk factors than we did.... ...but the findings of the 2 studies point to similar overarching risks – larger herd size – factors that may allow introduction of new pathogens – factors that allow increased effective contacts

Herd level risk factors: DVM opinion • E-mail survey of U.S. veterinarians engaged in cowcalf practice – 6 states: GA, FL, WV, IA, KS, NE – Information requested regarding the year prior to August 2012 – 61 veterinarians responded • Respondents asked to select from a list of possible herd-level risk factors Woolums et al. 2014

Factors identified by at least 50% of respondents as contributing to nursing calf BRD Factor

Percent identifying

weather

85%

inadequate colostrum consumption

73%

introducing new cattle

63%

failure to give calves respiratory vaccines

63%

failure to give cows respiratory vaccines

60%

calf diarrhea in the herd

52%

vitamin/mineral deficiency

52%

protein/energy deficiency

50%

calving in confinement

50%

BVDV PI in herd

50% Woolums et al., 2014

Herd Level Risk Factors, Case-Control Study • Developed questionnaire – questions included guided by results of mail survey • Phone interviews – same interviewer called matched control and case herds – interviewer did not know which was which

• Interviewers asked questions regarding management and disease in previous summer • Herds interviewed in winter of 2012, 2013, and 2014

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Herd Level Risk Factors, Case-Control Study • Case-control study of herd level risk factors for nursing calf BRD • Identified affected herds through announcements at national meetings and by email – case herds: treated ≥ 5% of nursing calves for BRD – control herds: treated ≤ 0.5% of nursing calves for BRD • randomly selected from same vet practice as case herd

– 2 control herds enrolled for each case herd

• Herds in NE, SD, and ND

Woolums et al., 2018

• Management practices considered – Were cows and calves were managed in more than one group? – Was intensive grazing was used? – Did cattle have fence-line contact with other herds? – Were cows or calves were given supplemental feed? – Were any cattle were brought onto the farm from outside sources? – Were cows were synchronized after calving? – Were cows were checked for pregnancy? – Were cattle were tested for bovine viral diarrhea (BVD) virus? – Were cows and calves were ever moved more than one mile on foot? – Length of calving season? – Did any calves develop diarrhea? – Were respiratory vaccines given to cows and/or calves? – Were any cows/heifers treated for respiratory disease?

Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

Results

Characteristics of case and control herds

• 84 herds enrolled

• 29 herds from Nebraska • 23 from from North Dakota • 32 herds from South Dakota

• Significant risk factors: • Number cows/heifers calving • Versus herds with < 150 cows • If 150 – 499 cows: OR = 7.9 (2.0 – 31) P = 0.03 • If ≥ 500 cows: OR = 12 (2.0 – 70) P = 0.02

OR = 3.3 (1.2 – 9.2) P = 0.05

• Cows or heifers synchronized • Versus not: OR = 4.5 (1.5 – 14) P = 0.02

Information on Risk Factors: Limitations • Currently, most of what we know about risk factors is based on diagnosis by clinical signs – Reliability? • Of 16 dairy calves with postmortem pneumonia: – Producer correctly identified 9 with pneumonia – Did not identify pneumonia in any calves without pneumonia – Sensitivity: 56%

•

Case Herds

173

325

Percent first calf heifers in herd

13%

15%

Calving season length

93 days

95 days

Average age of calves at weaning

183 days

180 days

Average weight of calves at weaning

249 kg

256 kg

median (range)

– 30 case herds – 54 control herds

• Intensive grazing • Versus not:

Control Herds Number of cows and heifers calving

Specificity: 100% Sivula et al., 1996

(40 – 1490) (0 - 30%)

(37-218)

(150 – 260) (170 – 345)

median (range) (80-930) (0 – 25%)

(36-259)

(120-245) (181-352)

• Conclusion: – Factors that may increase effective contacts between calves appear to increase risk for preweaning BRD • herd size • synchronization • intensive grazing

• Next steps: test methods to modify the effect of these factors – Improve calf immunity through early vaccination? – Decrease sizes of groups when calves are congregated?

Information on Risk Factors: Limitations • Nearly all of what we know about herd level risk factors is based on interviews or surveys of producers – Possibility of inaccurate or incomplete reporting

• Researchers don’t always ask the same questions in their studies

Estimate for feedlot BRD clinical diagnosis •

Sensitivity: 62%

Specificity: 63% White and Renter, 2009

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Missouri VMA 127th Annual Convention January 26, 2019

Dr. Amelia Woolums, Mississippi State University

Herd level risk factors: common themes • Factors that allow introduction of new pathogens – New cattle brought on to farm – Visitors • Factors that increase opportunities for effective contacts – intensive grazing – synchronization of cows/heifers – longer calving season

Herd level risk factors: some questions remaining • What situations lead to most risky effective contacts? – How can these be limited or avoided?

• Does vaccination of cows or calves make any difference? – If so, when or what is useful?

– creep feeding

Herd level risk factors: questions remaining • Does suboptimal passive (maternal) immunity play an role? • Role of – genetics? – nutrition? – weather?

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Conclusion • At this time, limiting practices that – promote introduction of new pathogens, or – increase close contact among cows and calves ...may be useful strategies to limit disease in herds with preweaning calf BRD

• Stay tuned for more information

Equine

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Equine

Elizabeth A. Giuliano, DVM, MS, DACVO

Professor, Department of Veterinary Medicine and Surgery University of Missouri - College of Veterinary Medicine Columbia, Missouri

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MVMA 2019 CONFERENCE Title, Description, and Proceedings ESSENTIALS TO THE EQUINE OPHTHALMIC EXAMINATION Elizabeth A. Giuliano, DVM, MS Diplomate, ACVO Professor and MU-VHC Ophthalmology Section Head SUMMARY: Ophthalmic Examinations can often be intimidating for the new equine or mixed animal practitioner or perhaps, to our more seasoned veterans who have not had a great deal of experience dealing with ophthalmic diseases. The goals of this lecture are as follows: • Provide an overview to the basic instrumentation, supplies and diagnostic pharmaceuticals required for a complete ophthalmic exam in the equine patient • Discuss the key components of the “minimum ophthalmic data base” • Provide helpful tips to ensure success in performing the complete ophthalmology exam for horses. HELPUL SUMMARY POINTS: • Equine ophthalmic examinations should include the following: a good history and signalment, examining the patient in a well-lighted as well as darkened environment. • The environment should be quiet and away from major distractions. • Typically, equine patients require systemic sedation and local nerve blocks to ensure that a thorough ocular exam is acquired and importantly to prevent additional injury to the patient. • Always strive to acquire the “minimum ophthalmic data base” to best diagnose and treat your equine ophthalmic patients. Rarely, an aspect of the complete ophthalmic exam will be forfeited (example: tonometry should not be performed on an eye with a descemetocele due to risk of globe rupture). • Components of the minimum ophthalmic data base include: menace response, direct and consensual pupillary light reflex, palpebral reflex, Schirmer tear test, fluorescein stain, and tonometry. This lecture will discuss what components of the minimal ophthalmic data base are sometimes not performed in horses and why. • Note that the menace response, PLR, and palpebral reflex should be performed prior to the administration of any systemic sedation. • Additional diagnostics typically performed in an awake patient include: conjunctival / corneal cytology and/or culture and sensitivity, conjunctival biopsy, and nasolacrimal flush. BASIC INSTRUMENTATION: A thorough ophthalmic examination may be performed with a minimum of diagnostic instrumentation. Basic instruments include: - magnifying source – (e.g. Optivisor loupe) - power source – (e.g. Welch-Allyn (W-A) 3.5V halogen handle) - focused light source – (e.g. Welch-Allyn Finoff transilluminator) - direct ophthalmoscope head - attaches to W-A 3.5V handle - 20 - 15 diopter condensing lens - tonometer (e.g.:Tonopen) - nasolacrimal cannula - thumb forceps - scraping blade - spatula or surgical blade (clip-on end) SUPPLIES & DIAGNOSTIC PHARMACEUTICALS Consumable materials that should be readily available are: - Schirmer tear test (STT) strips - sterile fluorescein strips - culturette swabs (mini-tip) - cotton swabs - sterile eye wash irrigating fluid or sterile saline - dilating agent - 1% tropicamide (Mydriacyl) - topical anesthetic solution - 0.5% proparacaine (e.g. Alcaine) USE OF A TRANSILLUMINATOR

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The transilluminator powered by a 3.5V handle is used to closely inspect extraocular structures including the lacrimal caruncle, the nasolacrimal puncta, the leading edge of the third eyelids, the tarsal (meibomian) glands, and the limbus of each eye. Conjunctival vessels are differentiated from episcleral (ciliary) vessels. Translucency of the cornea is determined. Importantly, a combination of illumination techniques is highly useful and all can be achieved using a simple transilluminator or bright pen-light. They include: • Direct focal illumination • Tangential illumination • Retroillumination Intraocular structures in the anterior segment of the eye may also be examined. The light is directed obliquely across the anterior portion of the globe and the depth and clarity of the anterior chamber is noted (eg. tangential illlumiation). The color and surface contour of the iris and the size and symmetry of the pupillary openings are observed. Direct and consensual pupillary responses are tested. Recall that the use of dilating agents will invalidate pupillary responses for several hours. Direct the light through the pupils and observe the fundic reflexes. The presence and color of tapetum will determine the color of the fundus reflex. The lenses are normally translucent and allow reflected light to fill the pupil spaces. In most horses the tapetal reflection is gold to green and sometimes red. Opacities are frequently detectable by this technique which is referred to as retroillumination. A partial or complete absence of a fundus reflex indicates opacification involving one or more portions of the normally transparent parts of the eye. SCHIRMER TEAR TEST The Schirmer tear test (STT) is a method of measuring basal and reflex tear production in horses when deficient tear volume (aqueous component) is suspected. It is performed by inserting a sterile filter paper strip into the lower, middle conjunctival fornix of each eye. The strip is inserted and left in place for 60 seconds, then removed and the length of the filter paper that has been moistened by the tear fluid is measured on a mm scale. Deficiencies in aqueous tear production have rarely been reported in the horse, but are receiving more attention in recent years (particularly as related to qualitative, not simply quantitative, tear film abnormalities). Therefore, STT is not commonly performed as part of the routine minimal ophthalmic data base in this species. Nevertheless, a STT would be indicated if evidence of cranial nerve dysfunction were present (after trauma, facial paralysis), if the corneal or conjunctiva appear dry, if muco-purulent discharge is present, when corneal vascularization or ulceration if evident, or if an underlying problem for a corneal or conjunctival problem cannot be determined. Normal values for horses have been reported and a wide variability between eyes and between the same eye during different times of the day have been published. This variability seems to be unrelated to signalment, housing, or season. In general, the equine STT values are much greater than those reported for either the canine or feline species. Healthy horses have been reported to have be between 15 and 20 mm. 30 seconds. In general, repeatable measurements of less than 10 mm wetting/min should be considered abnormal in conjunction with clinical signs.

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CONJUNCTIVAL-CORNEAL CULTURES & SCRAPINGS Cultures of the ocular surface are necessary for definitive diagnosis of severe, chronic, or nonresponsive infections. For conjunctival culture, the lower eyelid is everted and a sterile cotton or rayontipped swab in applied to the ventral fornix in front of the third eyelid. To insure adequate tissue contact the swab tip is gently pressed against the conjunctiva and rotated so as to slightly elevate the conjunctival tissue. The swab is then removed and inserted into the transport tube which contains an ampule of transport media. The ampule is ruptured and the sample is sent to the laboratory as soon as possible. Some specimens may be refrigerated depending upon the type of culture, i.e., the organism suspected. For corneal cultures, the swab is applied to the margin of the ulcerated or necrotic lesion. Ideally, cultures should be taken prior to instillation of topical agents, including topical anesthetic. However, in cases of corneal ulcers, one drop of topical anesthesia will aid patient compliance and has been shown to have minimal effects on culture results. Contamination is avoided by being cautious not to touch the skin or hair with the swab tip. Cytologic evaluation of ocular surface cells may be quite helpful in making a definitive diagnosis in cases of inflammatory or neoplastic lesions. For cytology, spatula collection is preferred over swabs for removal of surface cells at affected sites. Many ophthalmologists now prefer the use of “cytobrushes” for sample collection as the cells are often less damages during the collection process. Samples for conjunctival or corneal cytology are collected after discharges are cleansed from the eye and topical anesthetic has been instilled. Several drops of topical anesthetic solution are instilled over a 2-minute period (e.g., 1 drop every 30 seconds). Platinum spatulas are specifically designed for ocular use, however, less expensive spatulas, such as pharmaceutical or chemical spatulas or the blunt, snap-on end of a surgical blade, may also be used. Scrapings are collected by placing the spatula or blade (blunt end) perpendicular to the surface, by pressing firmly against the tissue, and then pulling along the surface. Samples collected from scrapings 2

should be gently blotted onto glass slides and air dried. A minimum of three slides should be prepared, one for a modified Wright's stain, one for a Gram's stain, and the remaining one for special staining if needed. Cytologic findings of greatest diagnostic interest are the presence of inflammatory or neoplastic cells or the presence of microorganisms. FLUORESCEIN STAINING Fluorescein dye is used diagnostically in veterinary ophthalmology for a number of reasons. The most common and important reason for placing fluorescein stain onto the eye is to detect a corneal ulcer. Recall that the corneal stroma is hydrophilic and, therefore, the water soluble fluorescein has a marked affinity for exposed stromal tissue. An area of positive staining will be noted by a bright yellow-gold appearance under room light conditions or using a focal white light. A cobalt blue filter on the tip of a hand-held transilluminator or an ultraviolet (UV) light will excite the fluorescein and any area of positive staining will appear bright green. Keep in mind that fluorescein does not stain epithelial surfaces or Descemet's membrane. Fluorescein may also be used to determine patency of the nasolacrimal (NL) drainage ducts (Jones test). The most common way to apply Fluorescein stain to the equine eye is to place a sterile fluorescein strip in a 3-ml syringe, fill the syringe with sterile eyewash and replace the plunger, and then squirt the solution through the hub of a 25-guage needle in which the actual needle has been manually broken off. Care should be taken to properly dispose of the needle tip. The horse is then allowed to blink several times and excess stain can be removed with gentle irrigation. The eye is scanned with a focused light (typically with a cobalt filter or UV light). A short time later, usually in 5 minutes, the nares are inspected using the focused light to determine if fluorescein has passed through the nasolacrimal ducts. If dye has not drained into the nostrils by 20 to 30 minutes after instillation, obstruction of the duct is may be suspected and NL irrigation may be indicated. Sometimes, a negative Jones test may even be normal in the horse due to the large volume capacity of the nasolacrimal duct. As with all diagnostic tests, their findings should be interpreted in light of the horseâ&#x20AC;&#x2122;s clinical signs. Please remember to dispose of any diluted fluorescein stain made up at the end of EACH DAY to avoid bacterial contamination. NASOLACRIMAL IRRIGATION Nasolacrimal flushing can be performed retrograde (i.e. from the distal naresâ&#x20AC;&#x2122; opening) or normograde (i.e. from the upper or lower eyelid puncta). Sedation is almost always required. The nasal puncta can be cannulated using a 4 to 6 Fr canine urinary catheter coated in lidocaine gel. Digital pressure is usually needed to prevent normograde loss of fluid. A 10 to 20 ml syringe, filled with eyewash, is attached and gentle irrigation of the nasolacrimal duct is performed until fluid exits the upper puncta near the medial canthus. Be aware that violent sneezing often ensues when performing retrograde NL flushing. Normograde flushing can be attempted using a lacrimal canula or 20-guage IV catheter once the stylet has been removed. If resistance is encountered to attempts at irrigation, an obstruction is probably present. Continued gentle pressure may flush out minor obstructions. Excessive pressure should be avoided so that the duct system is not further damaged. OPHTHALMOSCOPY Either direct or indirect ophthalmoscopy may be used to examine the posterior portion of the eye, i.e., the vitreous and fundus. The monocular direct ophthalmoscope is commonly used in general practice for examining the back of the eye. There are two dials on the direct ophthalmoscope head - a smaller horizontal dial that controls the size and shape of the light beam and a larger vertical dial that controls the focal point of the light beam. The horizontal dial is set to project a large circular white light beam and the vertical dial is adjusted to focus on the structure(s) of interest, e.g., start at 0 for viewing the fundus. By adjusting the focusing distance of the direct ophthalmoscope, the examiner may use the instrument to examine all visible intraocular structures. Its most common use is in examination of the posterior portion of the globe. When the vertical dial is set on 0, subtracting diopters (i.e., -1, -2,-3, etc.) moves the focal point away from the viewer. Conversely, when diopters are added (e.g., +1,+2,+3, etc.) the focal distance is brought closer to the viewer. Note: if the examiner normally wears corrective eyewear, and removes his/her glasses when performing direct ophthalmoscopy, the refractive power of the examiner will need to be adjusted for (thus, the diopter power needed to achieve focus for various ocular structures may vary slightly from person to person). Indirect ophthalmoscopy involves using a focused light and a condensing lens (20 - 15 diopters) to view the fundus. A head-mounted light source combined with a set of prisms may be used and provides the viewer with a binocular view. A hand-held light may also be used. A finoff transilluminator is recommended as a focal light source for performing monocular indirect ophthalmoscopy. See the attached table for comparing the advantages and disadvantages of direct and indirect ophthalmoscopic techniques. Note, this author strongly advocates the use of indirect vs. direct ophthalmoscopy for posterior segment examination! The vitreous is examined for congenital remnants (retained hyaloid structures) and other opacities (degenerative materials, hemorrhage or exudates). Examination of the fundus involves studying the optic disc 3

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(papilla), retinal vessels (note that horses have a paurangiotic retina with short retinal vessels extending only a few millimeters from the optic nerve head), tapetal fundus (tapetum), and nontapetal fundus (nontapetum). Fundus examination should begin by identifying the optic disc and by evaluating its size and shape. The horse’s optic nerve is located slightly oval in the horizontal direction and located just ventral to the tapetalnontapetal junction. Note that the horse’s optic nerve is positioned laterally in the globe so the examiner must move nasally to find it. The tapetum, the upper, brightly-colored portion of the fundus, will have variable color depending on the horse’s skin coloration. For example, it is not uncommon to see red and green tapetal coloration patterns in Paint horses. Abnormal equine funduscopic findings are quite varied and include abnormalities of the optic disc, chorioretinal scars, and retinal detachment to name just a few. A complete discussion of equine ocular disease is well beyond the scope of these notes. Therefore, the reader is referred to the suggested reading below for a more thorough discussion of abnormal equine ophthalmic examination findings. TONOMETRY Intraocular pressure (IOP) measurement, or tonometry, is indicated in horses that have corneal edema, a red or painful eye, orbital trauma, a history of glaucoma in the opposite eye, a lens luxation, and for diagnosing glaucoma (elevated pressure) and uveitis (low pressure). It is also very useful in assessing response to therapy when treating any of the aforementioned ocular conditions. Applanation tonometry (Tonopen) provides accurate and reproducible intraocular pressure readings in veterinary patients and is becoming increasingly used in general equine practice. Applanation tonometers have several advantages over the Schiotz tonometer. They are highly accurate, their readings are less affected by corneal disease, they can be used to measure intraocular pressure in vertically as well as horizontally positioned corneas, and are very easy to use, making them the instrument of choice for measuring intraocular pressure in domestic animals. There are many different studies examining normal intraocular pressures in horses and the effects of systemic sedation, head position, eyelid blocks, etc and the reader is referred to the suggested reading for more details. The mean normal equine IOP ranges from 15 to 30 mm Hg, with the IOP of the left and right eyes of any given horse being within 5 to 8 mm Hg of each other. An IOP greater than 30 to 35 mm Hg is usually diagnostic of glaucoma. The rebound tonometer (tonopen) is increasingly gaining in popularity and can be used without topical anesthesia. OTHER (MORE ADVANCED; GOOD REFERALS) EXAMINATION AND DIAGNOSTIC PROCEDURES • Aqueous paracentesis • Vitreous paracentesis • Retinoscopy • Flourescein angiography • Corneal esthesiometry • Ultrasound Pachymetry • Specular Microscopy • Gonioscopy • Electroretinography • Ocular ultrasonography • Radiography, MRI, CT

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COMPARISON OF OPHTHALMOSCOPIC TECHNIQUES

DIRECT OPHTHALMOSCOPE Advantages

Disadvantages

1. Portability

1. Decreased penetration of cloudy media

2. Inexpensive

2. Small field of vision

3. Image more magnified

3. Short working distance

4. Direct upright image

(closer to the animal's head) 4. No stereopsis 5. Inability to examine peripheral retina

BINOCULAR INDIRECT OPHTHALMOSCOPE Advantages

Disadvantages

1. Larger field of view

1. Inverted reversed image

2. Greater distance from patient's head

2. More expensive than direct

3. Stereopsis

ophthalmoscope

4. Light penetrates cloudier media

FOCAL LIGHT SOURCE AND LENS AS OPHTHALMOSCOPE Advantages

Disadvantages

1. Inexpensive

1. No stereopsis

2. Portable

2. Inverted reversed image

3. Large field of view 4. Distance from patient's head IN SUMMARY, * When presented with any ophthalmic abnormality, concern for the horse’s vision and ocular comfort should guide the practitioner’s diagnostic and therapeutic plan * The patient should be examined first at a distance, and then at eye level in both bright and dark lighting. 5 231

* * *

The complete ophthalmic exam with its â&#x20AC;&#x153;minimal ophthalmic dataâ&#x20AC;? should be acquired during all ophthalmic examinations with some exceptions for the horse (discussed in lecture). Components of the minimum ophthalmic data base include: menace response, direct and consensual pupillary light reflex, palpebral reflex, Schirmer tear test, fluorescein stain, and tonometry Additional ocular diagnostic procedures routinely performed by the general practitioner include nasolacrimal flushing, conjunctival/corneal swabs for cytology and culture, and conjunctival biopsy.

SUGGESTED READING: Textbook: Equine Ophthalmology. 3RD EDITION Editor: Brian C. Gilger, DVM, MS, DACVO

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MVMA 2019 CONFERENCE Title, Description, and Proceedings TREATMENT MODALITES FOR COMMON EQUINE OHPHTHAMIC DISEASES Elizabeth A. Giuliano, DVM, MS Diplomate, ACVO Professor and MU-VHC Ophthalmology Section Head OBJECTIVES OF THE PRESENTATION • This lecture will provide an overview of commonly acquired equine corneal disease that require treatment. • The two most commonly encountered acquired corneal diseases affecting horses world-wide are ulcerative keratitis and corneal stromal abscess. • The lecture will use case examples to emphasize the clinical presentation, diagnostic approach, and treatment options of these common acquired equine corneal diseases. • PLEASE NOTE: The reader is encouraged to attend lecture, as these notes are intended to supplement (not summarize) what will be covered during lecture. The author strongly believes that veterinary ophthalmology cannot be learned from written notes. ANATOMY/PHYSIOLOGY Cornea and sclera comprise the outer fibrous tunic of the eye. The corneoscleral junction is termed the limbus. The cornea is the main refractive structure of the eye. The thickness of the central equine cornea is reported between 770 and 793 µm. The radius of curvature in an average adult horse is approximately 16.5 mm vertically and 18 mm horizontally. Four layers are identified histologically: • • • •

The epithelium and its basal lamina The stroma Descemet's membrane The endothelium

The epithelium is the main ocular surface barrier to entry of pathogenic organisms and penetration of therapeutic agents. The cornea receives sensory innervation from the ophthalmic branch of the trigeminal nerve (CN V). Normally, the cornea exists in a relatively dehydrated state (called deturgescence) through the barrier and pump functions of the epithelium and endothelium, respectively. The endothelium has the greater role in maintaining deturgescence. CORNEAL PATHOLOGIC RESPONSES Corneal clarity is essential for normal vision and is due to: • • • • •

Absence of blood vessels Deturgescence (relative dehydration) A specific size and arrangement of collagen lamellae in the stroma Absence of pigment Relative acellularity

Any decrease in clarity is indicative of a pathologic process. Pathologic responses include vascularization, edema, scarring, lipid and/or mineral deposition, pigmentation, inflammatory cell infiltration, and

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destruction from degradative enzymes ("melting"). A combination of these pathologic responses is commonly observed. When presented with any ophthalmic abnormality, a complete ophthalmic examination should be performed (see lecture notes elsewhere from this meeting). Typically, horses require both systemic sedation and regional eyelid blocks for the ophthalmic examination to be complete. Some components of the complete ophthalmic exam should not be formed if the globe is at risk of (or has) ruptured (e.g. tonometry). Diagnostic tests routinely performed in the work up of equine acquired corneal disease include Fluorescein staining, corneal cytology, and culture with sensitivity. FLUORESCEIN STAINING Fluorescein dye is used diagnostically in veterinary ophthalmology for a number of reasons. The most common and important reason for placing fluorescein stain onto the eye is to detect a corneal ulcer. Recall that the corneal stroma is hydrophilic and, therefore, the water soluble fluorescein has a marked affinity for exposed stromal tissue. An area of positive staining will be noted by a bright yellow-gold appearance under room light conditions or using a focal white light. A cobalt blue filter on the tip of a hand-held transilluminator or an ultraviolet (UV) light will excite the fluorescein and any area of positive staining will appear bright green. Keep in mind that fluorescein does not stain epithelial surfaces or Descemet's membrane. Fluorescein may also be used to determine patency of the nasolacrimal (NL) drainage ducts (Jones test). The most common way to apply Fluorescein stain to the equine eye is to place a sterile fluorescein strip in a 3-ml syringe, fill the syringe with sterile eyewash and replace the plunger, and then squirt the solution through the hub of a 25-guage needle in which the actual needle has been manually broken off. Care should be taken to properly dispose of the needle tip and to dispose of any fluorescein stain solution at the end of EVERY day. The horse is then allowed to blink several times and excess stain can be removed with gentle irrigation. The eye is scanned with a focused light (typically with a cobalt filter or UV light). A short time later, usually in 5 minutes, the nares are inspected using the focused light to determine if fluorescein has passed through the nasolacrimal ducts. If dye has not drained into the nostrils by 20 to 30 minutes after instillation, obstruction of the duct is may be suspected and NL irrigation may be indicated. Sometimes, a negative Jones test may even be normal in the horse due to the large volume capacity of the nasolacrimal duct. As with all diagnostic tests, their findings should be interpreted in light of the horseâ&#x20AC;&#x2122;s clinical signs.

CONJUNCTIVAL-CORNEAL CULTURES & SCRAPINGS Cultures of the ocular surface are necessary for definitive diagnosis of severe, chronic, or nonresponsive infections. For conjunctival culture, the lower eyelid is everted and a sterile cotton or rayon-tipped swab in applied to the ventral fornix in front of the third eyelid. To insure adequate tissue contact the swab tip is gently pressed against the conjunctiva and rotated so as to slightly elevate the conjunctival tissue. The swab is then removed and inserted into the transport tube which contains an ampule of transport media. The ampule is ruptured and the sample is sent to the laboratory as soon as possible. Some specimens may be refrigerated depending upon the type of culture, i.e., the organism suspected. For corneal cultures, the swab is applied to the margin of the ulcerated or necrotic lesion. Ideally, cultures should be taken prior to instillation of topical agents, including topical anesthetic. However, in cases of corneal ulcers, one drop of topical anesthesia will aid patient compliance and has been shown to have minimal effects on culture results. Contamination is avoided by being cautious not to touch the skin or hair with the swab tip. Cytologic evaluation of ocular surface cells may be quite helpful in making a definitive diagnosis in cases of inflammatory, infectious or neoplastic lesions. For cytology, this author used the sterile back-end of a # 10 blade for careful/gentle removal of surface cells at affected sites. Samples for conjunctival or corneal cytology are collected after discharges are cleansed from the eye and topical anesthetic has been instilled. Several drops of topical anesthetic solution are instilled over a 2-minute period (e.g., 1 drop every 30 seconds). Platinum spatulas are specifically designed for ocular use, however, less expensive spatulas, such as pharmaceutical or chemical spatulas or the blunt, snap-on end of a surgical blade, may also be used. Scrapings are collected by placing the spatula or blade (blunt end) perpendicular to the surface, by pressing firmly against the tissue, and then pulling along the surface. Samples collected from scrapings should be gently blotted onto glass slides and air dried. A minimum of three slides should be prepared, one for a modified Wright's stain, one for a Gram's stain, and the remaining one for special staining if needed. Cytologic

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findings of greatest diagnostic interest are the presence of inflammatory, infectious, or neoplastic cells or the presence of microorganisms. CLINICAL SIGNS COMMONLY ASSOCIATED WITH EQUINE ACQUIRED CORNEAL DISEASE • Ocular pain (blapharospasm, epiphora, chemosis, photophobia) • Serous to mucoid ocular discharge • Focal or diffuse corneal edema • Loss of corneal epithelium, stroma, or both (ulcer) • Corneal neovascularization • Aqueous flare • Hypopyon • Keratomalacia (corneal melting) • Cellular infiltrate (white to yellowish)

EQUINE ACQUIRED CORNEAL DISEASE • Ulcerative Keratitis (may be sterile/traumatic, bacterial, fungal, or mixed infection) • Corneal laceration • Corneal foreign body • Stromal abscess • Nonulcerative keratouveitis (NUKU) • Eosinophilic keratoconjunctivitis • Equine herpesevirus (EHV) • Corneal diseases • Intraocular disease with secondary corneal abnormalities • Neoplasia • Idiopathic GENERAL THERAPEUTIC CONSIDERATIONS WHEN TREATING HORSES FOR PAINFUL OCULAR DISEASE: Specific medical or surgical therapies unique to particular equine ocular disease discussed in lecture will be reviewed during the presentation. A detailed pharmacologic review of a wide variety of therapeutic agents currently used in horses with acquired corneal disease is beyond the scope of these notes and the reader is referred to the suggested readings below. It is worth noting that the majority of ocular pharmacokinetic ophthalmic drug studies have been performed in non-equine species, rendering much of the current clinical medical practice to be based on extrapolation from other species. This approach is problematic in that horses may be more prone to complications when systemic antimicrobial and anti-inflammatory agents are used than what is commonly observed using similar therapeutic strategies in other species. Additionally, there are no doubt significant differences in the pharmacokinetics of topical drugs resulting from such factors as relative ocular size, tear production and flow dynamics, blink rate, and presence and motility of the third eyelid. The overall medical goal when treating horses with acquired ocular disease is to achieve therapeutically effective levels of an appropriate drug or combination of drugs at the affected site. Specifically, the clinician’s goals are to: (1) decrease/control inflammation of the affected tissue, (2) prevent secondary infection, and (3) treat specific bacterial, fungal, or parasitic disease diagnosed by cytology, biopsy, and/or culture and sensitivity testing which may be the primary cause of disease or secondary to some other primary pathologic process (e.g. corneal neoplasia with secondary bacterial infection). Considering the essential role of the cornea to vision as well as ocular comfort, therapeutic agents are frequently administered to address the aforementioned 3 primary treatment goals. Often, regardless of the primary etiologic process, equine acquired corneal and intraocular diseases are treated with a combination of systemic and topical medications. Antimicrobial therapy Topical antimicrobial therapy is routinely used in the treatment of equine corneal disease. Ointments should not be used in cases where the cornea has already, or is at risk of, rupture(d). Perhaps the most common broad spectrum topical antibiotic ointment routinely dispensed for ulcerative keratitis (including after surgical

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intervention) in North America is triple antibiotic ointment (e.g. neomycin, bacitracin, polymyxin) at a frequency of three to four times daily. Some clinicians may elect to use broad spectrum ophthalmic antibiotic ointment preparations containing topical steroids as well; however, in areas where fungal keratitis is prevalent, caution is recommended due to the risk of keratomycosis. Other relatively routine topical ophthalmic ointments dispensed include topical erythromycin, tetracycline, chloramphenicol, or non-ophthalmic preparations of silver sulfadiazine ointment. Marked differences in normal ocular equine surface flora exist among individual horses, geographic location, and seasonal variation. Due to this inherent variability of possible or primary infectious microbes to affect the equine cornea, empirical treatment with standard antibiotics may be unsuccessful, especially if the horse has already been treated with topical or systemic antimicrobials prior to referral to a specialist. Whenever possible, further diagnostic testing is advisable. Even then, however, in-vitro sensitivity data may not necessarily reflect in-vivo clinical response. Systemic antimicrobial agents are also sometimes used but in many cases, their use is empirical and may not be necessary. Furthermore, the route and type of antimicrobial administered is frequently based on nonmedical directives such as cost, availability, or ease of administration. The gastrointestinal tract of horses is highly susceptible to the adverse effects of antimicrobial drugs due to disruption of normal intestinal microbial populations and proliferation of enteropathogens. Diarrhea, especially when accompanied by signs of endotoxemia, is the usual clinical manifestation of this potentially life-threatening complication of systemic antimicrobial use in horses. Consequently, judicious use of any systemic antimicrobial is recommended and careful consideration must be made as to whether or not a systemic antimicrobial is truly indicated in each individual case. This decision process is often in stark contrast to the more â&#x20AC;&#x153;general therapeutic approachâ&#x20AC;? typical in small animal surgical ophthalmic patients where pre- and post-operative antimicrobial medications are routinely used. When deemed necessary due to obvious infection, antimicrobial selection is most appropriately made based on culture and sensitivity results of the affected area.

Anti-inflammatory therapy Veterinarians have long been familiar with the important role anti-inflammatory therapy plays in the treatment of periocular and ocular inflammation. Numerous systemic and topical corticosteroid and non-steroidal anti-inflammatory drugs (NSAIDs) are commercially available. Again, the challenge clinicians are continually faced with when electing to treat a horse with periocular and or ocular inflammation is to balance the potential therapeutic benefits of anti-inflammatory therapy against the occasional life-threatening risks of these drugs, especially when administered systemically. Systemic NSAID usage in horses is associated with the risk of both gastrointestinal disturbance and kidney damage. For these reasons, the use of systemic NSAIDs should be restricted to the requirements of necessity and not provided beyond the recommended treatment period without further veterinary examination or consultation. If complications occur, horses typically manifest reduced appetite, lethargy, colic, poor performance, diarrhea, weakness, abnormal water consumption, and/or discolored urine. While uncommon, due to the severity of potential complications, owners should be advised to seek veterinary attention promptly if adverse side-effects are observed. Furthermore, risks of systemic NSAID toxicosis are increased if the horse fails to drink a normal quantity of water, so clients should be urged to ensure that their horseâ&#x20AC;&#x2122;s water consumption be carefully scrutinized to ensure adequate intake. Common systemic NSAIDs currently used in horses with corneal disease when deemed necessary to control inflammation and help alleviate periocular discomfort are listed below. Topical ophthalmic ointments, solutions, and suspensions of steroid and NSAIDs (e.g. dexamethasone, prednisolone acetate, flurbiprofen, diclofenac, suprofen) are also readily available or can be obtained through a licensed compounding pharmacy.

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SUMMARY • When presented with any ophthalmic abnormality, concern for the horse’s vision and ocular comfort should guide the practitioner’s diagnostic and therapeutic plan • The patient should be examined first at a distance, and then at eye level in both bright and dark lighting. • The complete ophthalmic exam with its “minimal ophthalmic data” should be acquired during all ophthalmic examinations with some exceptions for the horse (discussed in lecture). • Components of the minimum ophthalmic data base include: menace response, direct and consensual pupillary light reflex, palpebral reflex, Schirmer tear test, fluorescein stain, and tonometry • Additional ocular diagnostic procedures routinely performed by the general practitioner when presented with acquired equine corneal disease include /corneal swabs for cytology and culture. • Any decrease in corneal clarity is indicative of a pathologic process. • Pathologic responses include vascularization, edema, scarring, lipid and/or mineral deposition, pigmentation, inflammatory cell infiltration, and destruction from degradative enzymes ("melting"). A combination of these pathologic responses is commonly observed. • Equine ulcerative keratitis and stromal abscess represent the most common ocular problems of horses and frequently result in significant morbidity with vision loss. • Prompt diagnosis and appropriate medical therapy should be initiated. • If adjunctive surgical therapy is indicated and the practitioner is not able to perform ophthalmic surgery him/herself, prompt referral to a veterinary ophthalmologist is strongly recommended. Suggested Reading (1) Textbook: Equine Ophthalmology 3RD edition

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Editor: Brian C. Gilger, DVM, MS, DACVO (2) Giuliano EA et al: Inferomedial placement of a single-entry subpalpebral lavage tube for treatment of equine eye disease, Vet Ophthalmol 3:153-156, 2000.

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MVMA 2019 CONFERENCE Title, Description, and Proceedings EQUINE OCULAR/PERIOCULAR NEOPLASIA Elizabeth A. Giuliano, DVM, MS Diplomate, ACVO Professor and MU-VHC Ophthalmology Section Head SUMMARY: Neoplastic adnexal disease represents one of the most frequently encountered ophthalmic problems of horses. The most common periocular neoplasms include squamous cell carcinoma (SSC), sarcoid, papilloma, lymphosarcoma, and melanoma. Various other, less common, equine adnexal and/or conjunctival tumours reported include angiomas, angiosarcomas, hemangiosarcoma, fibroma, fibrosarcoma, adenoma, adenocarcinoma, lacrimal gland carcinoma, basal cell carcinoma, and mast cell tumours. OBJECTIVES OF THE PRESENTATION • Equine ophthalmic examinations should include the following: a good history and signalment, examining the patient in a well-lighted as well as darkened environment. • The environment should be quiet and away from major distractions. • Typically, equine patients require systemic sedation and local nerve blocks to ensure that a thorough ocular exam is acquired. • Always strive to acquire the “minimum ophthalmic data base” to best diagnose and treat your equine ophthalmic patients. Rarely, an aspect of the complete ophthalmic exam will be forfeited (example: tonometry should not be performed on an eye with a descemetocele due to risk of globe rupture). • The purpose of this lecture is to discuss the most common types of equine adnexal and corneal/conjucntival neoplasms with special emphasis on their clinical appearance, clinical course of disease, and current as well as emerging new treatment modalities. DIAGNOSIS AND HISTORICAL OVERVIEW: The diagnostic approach to any periocular or ocular tumor is similar. Careful history and complete ophthalmic examination are essential. To better prognosticate and plan treatment, gentle digital orbital palpation of the orbital rim is helpful when examining periocular tumors to determine if local invasion into the surrounding tissues has occurred. Definitive diagnosis of any tumor requires histopathologic examination of biopsied tissue. Differential diagnosis for any particular neoplasm affecting the equine adnexa/periorbital area includes any other tumor type, conjunctivitis (lymphoid hyperplasia and follicular conjunctivitis), inflammatory lesions (abscesses, granulation tissue, foreign body reaction, solar-induced inflammation), and parasites (Habronema, Onchocerca, Thelazia). In some cases, more advanced diagnostic imaging may be indicated such as ocular ultrasound, skull radiographs, and/or computed tomography (CT) or magnetic resonance imaging (MRI). These additional diagnostics are especially helpful in cases where evidence of bony extension is likely to alter the prognosis or surgical planning of the case. Fine needle aspiration of the regional lymph nodes and/or parotid salivary gland should be performed in cases where lymphadenopathy is noted or if the tumour demonstrates local invasion. Controlled, prospective clinical trials are needed to better evaluate efficacies of various treatment methods for equine periocular neoplasia. Identical treatments administered to similarly-appearing tumour types can have different clinical outcomes. Reasons why some horses with a specific tumour type respond well to a particular therapeutic modality and other horses do not are poorly understood. Variability in clinical response is likely one important reason why a myriad of different treatment options exist for any given equine ophthalmic tumor. It is difficult to draw definitive conclusions regarding biologic behavior or response to treatment for many equine periocular neoplasms from a review of the veterinary literature. Treatment efficacy is challenging to critically assess because some studies are not designed with a control population for adequate comparison purposes and are often based on a subset of cases referred to specialty/teaching hospitals. Referral cases are frequently those that are refractory to “conventional” treatment modalities and may have already undergone treatment prior to being included in the study; therefore, the population of horses examined is skewed. Methods of data reporting (i.e. recurrence rate, disease-free interval, overall survival rate) also vary widely among publications. The extent of tumor involvement is not always well characterized, thus reported results may have been skewed toward a more favorable outcome in those cases with 1 239

superficial/smaller tumors. The reader should be aware of these limitations when reviewing the literature and/or when considering the most â&#x20AC;&#x153;appropriateâ&#x20AC;? treatment option for a particular case.

SQUAMOUS CELL CARCINOMA AND SARCOID Squamous cell carcinoma (SCC) is the most common neoplasm of the equine eye and ocular adnexa and the second most common tumor of the horse overall. Biological behavior of SCC varies depending on location but is typically locally invasive and slow to metastasize. Increased prevalence of SCC is associated with various environmental factors including geographic influences of increased longitude, decreased latitude, increased altitude, and increased mean annual solar radiation exposure. Additionally, a breed predilection exists for draft horses, appaloosas and paints. Mean age at diagnosis is approximately 11 years but a range of 3 to 26 years is reported. Sarcoids are cutaneous tumors of fibroblastic origin which often have proliferative and hyperplastic epithelial components and while metastasis is rare, recurrence is common, especially with the more invasive lesions. Size and location dictates their clinical significance. Periocular/eyelid sarcoids are common and may result in significant pathology to the eye either by disrupting normal eyelid function or by directly rubbing on the eye. Due to the close proximity of periocular structures to the globe, some treatments reported for use on sarcoids elsewhere on the body cannot be used on eyelids without risking significant damage to the globe. SQUAMOUS CELL CARCINOMA SCC should be suspected with any erosive, erythematous, cobblestone- or cauliflower-like raised ocular mass. Histologically, SCC has been subdivided into 4 basic types: plaque (i.e., carcinoma in situ), papillomatous, non-invasive SCC, and invasive SCC. Atypical, pigmented SCC has been reported, emphasizing the need for histologic confirmation of all abnormal periocular and ocular lesions. Unilateral involvement is most common, but horses may also be affected bilaterally. Carcinoma in-situ SCC often appears as hyperemic, erosive, eyelid plaques with dark-staining crusts that may undergo further cellular change to become papillomatous SCC. Alternatively, SCC may appear as a raised mass with a pink, cobblestone appearance, as is typical when affecting the third eyelid. Large, fleshy SCCs with variable degrees of ulceration, necrosis, and inflammation can infiltrate the orbit. Any chronic irritation may promote neoplastic transformation of epithelium into SCC especially at mucocutaneous junctions. Irritation from actinic and/or ultraviolet (UV) radiation has been thought to promote the development of SCC. Over-expression of the tumor suppressor protein p53, possibly mutated due to UV radiation, plays an important role in SCC development. The role of cyclooxygenase (COX) in the pathogenesis of equine SCC is still undetermined. Cycloxygenases are a family of enzymes responsible for conversion of arachidonic acid to prostaglandins and multiple isoforms of COX exist, with COX-1 and COX-2 being the most biologically active. High levels of COX-2 expression have been detected in a many human and veterinary neoplasms, including SCC of the head and neck. Correlations have been made in humans with head and neck SCC between overexpression of COX-2 in neoplastic tissues and poor prognostic factors. A limited number of investigations specifically examining the role of COX in naturally occurring equine ocular and periocular SCC have been conducted to date and interest in this area appears to have arisen largely from a single case report. Recurrence rates for SCC within a year of treatment have been reported between 50-66.7% with surgery alone, and range from 25-67% with surgery and ancillary irradiation or cryotherapy.. A 42.4% recurrence rate for ocular SCC with surgical excision, radiofrequency hyperthermia or both has also been reported. In another study, treatments included surgical excision, surgical excision with 90Sr beta irradiation, surgical excision with cryotherapy, surgical excision with radiofrequency, surgical excision with 137Cs interstitial radiotherapy, and/or immunotherapy, and the overall recurrence rate was 30.4%. Poorer prognosis is associated with SCC originating at the eyelid, compared to the third eyelid, nasal canthus or limbus. Larger sized masses, orbital extension, and recurrent SCC are associated with lower survival times. Metastasis of ocular SCC is uncommon and was observed in a case report, 6% of cases in one study, and 15.4% in another. Metastasis occurs most commonly to the regional (submandibular) lymph nodes, salivary glands, thorax, or extension into the orbit, sinus, and calvarium. Local invasion of the tumor often accompanies ulcerative necrosis and inflammation resulting in significant ocular discomfort. No single treatment modality has proven to be 100% effective in a large number of cases, and either the SCC itself or treatment complications may threaten both visual outcome and long term survival. SARCOIDS The clinical appearance of sarcoids varies and they are most commonly classified into 5 broad categories: occult, verrucose, nodular (A and B), fibroblastic (A and B), and mixed equine sarcoids. Occult sarcoid appears as an alopecic area with fine epidermal nodules. Verrucose sarcoids are thickened and hyperkeratotic with extensive flaking of the skin. Nodular type-A sarcoids are well defined, ovoid, and entirely subcutaneous, while type-B sarcoids are similar but involve the epidermis. Fibroblastic sarcoids appear fleshy

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and ulcerated and can be pedunculated (Type A) or have a broad base (Type B). Mixed sarcoids have one or more of the features of the other types of sarcoids. Sarcoids usually develop in young horses between 3 and 6 years of age; however, horses as young as yearlings have developed sarcoids. Nearly all breeds have been reported to develop sarcoids. Quarterhorses, Appaloosas, and Arabians may be at increased risk, while Standardbreds may be at decreased risk. Histologically, all clinical types of sarcoids have increased density of dermal fibroblasts (i.e., fibroblastic proliferation). Epidermal hyperplasia, hyperkeratosis, and rete peg formation have been found consistently in the verrucous and mixed types but not consistently in occult and nodular sarcoids. Sarcoids commonly invade into the subcutis and the deeper muscular structures around the eye. The pathological features of equine sarcoid are generally considered to be well-established; however, debate remains over possible etiologies. Sarcoids have long been thought to have a viral origin. This infectious origin was supported by the fact that epizootics have occurred in individual herds. Numerous studies have associated bovine papilloma virus (BPV) and equine sarcoids. Equine sarcoids appear to contain detectable viral DNA and RNA; they are also known to express the BPV types 1 and 2 major transforming protein, E5, but appear not to produce infectious virions. Genetic predisposition of equine sarcoid has been reported. Sarcoid occurrence was associated with the major histocompatibility complex (MHC) encoded class I equine leukocyte antigen (ELA) W3,B1 haplotype in Irish, Swiss, and French-bred Warmbloods . An association between sarcoid susceptibility and the MHC encoded class II allele ELA W13 has also been found in several breeds. Correlation between the development of sarcoids and heterozygosity for the equine severe combined immunodeficiency (SCID) allele may exist. Failure to induce complete regression of periocular sarcoids will frequently result in regrowth of the tumor and recurrence may be more aggressive (i.e., extensive local infiltration and faster growth). Therefore, if treatment is pursued, potent and aggressive therapy is recommended from the outset of treatment to more quickly destroy the tissue and prevent recurrences. Patients should be closely monitored with regular followup examinations and retreatment promptly initiated if recurrence is noted. However, the clinician must be aware that the extensive debulking around the eye is not possible due to the horse’s facial anatomy/lack of skin-flap surgical options. Use of certain treatment methods such as surface irritants should be used with great caution in the vicinity of the eye, lest the globe be secondarily damaged and vision compromised and/or distortion of palpebral tissues occurs. TREATMENT Equine eyelid abnormalities present unique challenges to veterinary ophthalmologists. The periocular skin in horses is tightly adherent to the underlying fascia and bone, often precluding successful reconstructive eyelid surgery for extensive eyelid tumors. If surgical reconstruction of the eyelid is unsuccessful, it is likely that the globe will be lost to the consequence of inadequate tear film maintenance/distribution and exposure keratitis. Due to the potentially devastating visual consequences for a horse affected by an extensive periocular neoplasm, a variety of treatment modalities have been employed with varying reported success rates. In most cases, surgical resection is performed to both confirm tumor type with histopathology and to decrease tumor volume to be treated by ancillary therapy. Numerous treatment methods, including surgical excision, cryosurgery, radiofrequency hyperthermia, immunomodulation, radiation brachytherapy, intralesional cisplatin, topical cytotoxic therapy (AW4-LUDES, 5-flurouracil cream, XXTERRA™, oil of rosemary, arsenic powder, engine grease, tea tree oil) and carbon dioxide laser ablation have been reported for equine periocular neoplasia. In most cases of equine eyelid/periocular neoplasia, surgical excision using sharp dissection (i.e., debulking all grossly affected neoplastic tissue) and adjunctive therapy is recommended for optimal long-term prognosis. Photodynamic therapy – Photodynamic therapy (PDT) is now an established modality for the treatment of a variety of ailments, including solid tumors, age-related macular degeneration, and atherosclerotic plaques. PDT involves the use of photochemical reactions mediated through the interaction of photosensitizing agents, light and oxygen. Selective uptake and retention of a photosensitizer by the target cells and microvascular endothelial cells, followed by irradiation with light of a specific wavelength, initiates necrosis and apoptosis of the target cells, vascular shutdown, and inflammation through formation of toxic singlet oxygen and free radicals. Tumor selectivity in treatment occurs through a combination of selective retention of the photoactive chemical by neoplastic cells and delivery of light to a highly-specific area. Photosensitizers are typically administered to the patient by intravenous injection. However, intravenous injection of a photoactive drug to a horse is not deemed feasible at this time. Recent studies have investigated the use of local PDT in the treatment of equine periocular tumors in both clinical patients and a murine model. In these on-going clinical investigations, a photoactive agent is injected locally into the wound bed immediately after surgical resection of the tumor and followed by light irradiation. Preliminary results have been favorable and this author has currently treated a total of 28 spontaneously occurring equine eyelid neoplasms (20 SCC, 9 sarcoids, and 3 melanomas) with surgical resection and local PDT. However, the real problem has become 3 241

that the company with a proven efficacious drug does not apparently wish to sell its drug to veterinarians so supply has become limited and very difficult to obtain. OTHER PERIOCULAR EQUINE NEOPLASMS Melanoma - Melanoma is a relatively uncommon periocular tumour of horses. In one review of 84 melanomas in horses, the most common sites of occurrence were under the tail (93.9%), the perianal region (43.0%), the lips (33.0%), and the eyelids (24.0%). Melanoma is most common in horses with grey or white hair. A slowly progressive, cutaneous, partially alopecic, pigmented mass of the eyelids is the typical clinical appearance of most equine adnexal melanoma. The size and location of the mass will dictate the clinical signs and older horses are predisposed to the development of melanoma, possibly because proliferation of melanocytes is a manifestation of aging. Equine melanomas have highly variable histologic and cytologic patterns that can make definitive diagnosis difficult. In one study, histologic characteristics of dermal melanomas were not predictive of malignancy most horses. Special stains may help confirm the diagnosis. Melanoma cells are usually positive for vimentin, S100, neuron-specific enolase, and Melan-A, and negative for cytokeratin. Currently, there is no single definitive diagnostic test capable of differentiating between benign and malignant melanocytic neoplasms or that would serve as a predictor for survival time. In one study, most metastatic melanomas showed overexpression of p53 and demonstrated apoptosis, but no differences were observed between malignant and benign dermal melanomas in growth fraction, S-phase index, or in DNA configuration; it was concluded that equine melanomas had substantially different phenotypic characteristics in comparison with melanocytic tumours in dogs, cats and humans. There are few reports of the treatment of equine adnexal melanomas, so success rates of various treatments are not known. Prior to initiating therapy, careful evaluation of the entire horse is recommended to rule out metastatic disease. There are no known studies on the effectiveness of intralesional chemotherapy or immunotherapy on melanomas. Oral cimetadine (dose 2.5 mg/kg of body weight orally every 8 hours) has been used to shrink non-ocular melanomas in horses, but no studies have been published on this treatment modality for adnexal melanomas. One study described the successful removal of a non-ocular dermal melanomas in a horse by CO2 laser ablation. Surgical resection and local PDT for a lower eyelid melanoma has also been performed (Giuliano et al. 2005), resulting in a disease free interval of 5 years. Excision of an eyelid melanoma is usually curative, because most of the masses are benign. However, a case report of a conjunctival melanoma described recurrence and metastasis. Horses may have dermal melanomas for years (range 1-6 years) before developing metastatic disease. Lymphosarcoma - Lymphosarcoma (LSA) is an uncommon neoplasm in the horse, especially when compared to other domestic animals, such as cows, dogs, and cats. Isolated case reports of equine adnexal LSA have been published. Ocular lesions occurred in 27% of horses with systemic LSA in one study. Infiltration of the eyelids and conjunctiva are the most common ocular manifestation of LSA. Orbital and/or third eyelid involvement can also occur. Immunohistochemical classification of equine malignant LSA has been reported in one study and revealed that equine LSA was composed of a heterogeneous cell population with most tumours containing B and T lymphocytes. Treatment options for horses affected with adnexal manifestations of LSA are limited. In one report with bilateral eyelid involvement, treatment with oral prednisolone (400 mg orally once daily) had no effect but intramuscular injection of Dexamethasone (30 mg every other day) resulted in marked reduction of eyelid swelling attributed to LSA during the limited time the horse received follow-up examinations. In a second case report of primary bilateral third eyelid LSA, the horse underwent complete third eyelid removal and remained disease free for 3 years. In general, the long-term prognosis for survival is poor for horses with LSA due to multicentric or disseminated disease. Conjunctival pseudotumours or bilateral nodular lymphocytic conjunctivitis Conjunctival pseudotumours or nodular lymphocytic conjunctivitis (NLC) appears as unilateral or bilateral, nodular or smooth, pink, nonulcerated conjunctival mass. Histopathologically, these lesions are characterized by nodular lymphoid components and presence of lymphocytes, plasma cells and histiocytes. Pseudotumours are suspected to have an immune-mediated pathogenesis based on the characterization of inflammatory cell infiltrate and the absence of infectious agents (bacterial, fungal, or parasitic) or foreign bodies. Surgical debulking and local administration of anti-inflammatory agents (i.e., intralesional corticosterial +/- topical corticosteroids) are the mainstays of therapy.

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• •

Additional research is warranted for equine periocular tumors. Currently, a universally acceptable standard treatment modality for a specific equine periocular tumor does not exist. The ideal therapy would produce complete tumor regression, a long disease-free interval, preserve eyelid function, and result in good cosmesis. No single treatment modality for equine periocular neoplasia has proven 100% effective and complications can threaten both visual outcome and longterm survival. Well-designed, prospective clinical trials with adequate case numbers and appropriate case follow-up are needed. Enhanced imaging techniques, genetic and biochemical insights into the pathogenesis of disease, and new therapeutic modalities represent exciting areas of potential development in the diagnosis and treatment of many equine periocular neoplasms.

Suggested Reading (1) Textbook: Equine Ophthalmology. 3rd edition Editor: Brian C. Gilger, DVM, MS, DACVO (2) Giuliano, EA. Equine Periocular Neoplasia – Current Concepts in etiopathogenesis and Emerging Treatment Modalities. Equine Veterinary Journal, Supplement 3

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MVMA 2019 CONFERENCE Title, Description, and Proceedings WHAT’S YOUR OPHTHALMIC DIAGNOSIS AND PLAN? Elizabeth A. Giuliano, DVM, MS Diplomate, ACVO Professor and MU-VHC Ophthalmology Section Head SUMMARY: Join Dr. Giuliano at the end of a long day of CE to participate in an interactive discussion of “what’s your diagnosis and plan?” Bring your own cases for review and discussion. This will be a fun, case based approached of a compilation of “guess what I just saw”? and “how on earth should I have treated XYZ?”. Colored copies of specific cases will be provided to attendees at the time of lecture.

Suggested Reading (1) Textbook: Equine Ophthalmology. 3rd edition Editor: Brian C. Gilger, DVM, MS, DACVO (2) Giuliano EA. Equine periocular neoplasia: Current concepts in aetiopathogenesis and emerging treatment modalities. Equine Veterinary Journal 2010; Suppl (37):9-18. (3) Giuliano EA, MacDonald I, McCaw DL, Dougherty TJ, Klauss G, Ota J, Pearce JW, Johnson PJ. Photodynamic therapy for the treatment of periocular squamous cell carcinoma in horses: a pilot study. Veterinary Ophthalmology 2008;11(Suppl 1):27-34

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Tamara Gull, DVM, PhD, DACVIM (LA), DACVPM, DACVM Bacteriology Section Head - University of Missouri Veterinary Diagnostic Lab. University of Missouri - College of Veterinary Medicine Columbia, Missouri

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Molecular diagnostics in equine medicine Tamara Gull DVM, PhD, DACVIM(LA) DACVM University of Missouri Veterinary Medical Diagnostic Laboratory

What are molecular diagnostics? • Any test using the detection of nucleic acid • DNA (bacteria and viruses) • RNA (some viruses)

• Most use PCR (polymerase chain reaction) technology

• PCR may be conventional or real-time • Genome sequencing used for some tests • Next-generation sequencing in development but not yet widely used

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Remember what PCR is? • Conventional PCR • • • • • •

Sample DNA is denatured with heat Primers complementary to the target DNA sequence are provided Primers anneal with target DNA as temperature is lowered Taq polymerase extends primers to produce copies of target DNA sequence Cycle is repeated up to 50x Products are run on a gel and bands of appropriate size are excised and may be sequenced

• https://www.youtube.com/watch?v=2KoLnIwoZKU

Real-time PCR vs. conventional PCR • • • •

Similar to conventional PCR but includes a fluorescence detector Primers contain a fluorescent molecule and a quencher The fluorescent probe is released when the target gene is amplified Fluorescence detection can both indicate positivity and allow quantification of number of target genes (number of organisms) present in sample • No gel electrophoresis or sequencing required • Faster than conventional PCR • https://www.youtube.com/watch?v=1kvy17ugI4w 250

Advantages of molecular diagnostics • Generally higher sensitivity than culture-based tests

• However, detects DNA from both live and dead organisms • Some tests may be “too sensitive”

• Test specificity varies

• Depends on the specificity and accuracy of the primers used • “General” primers such as 16S ribosomal protein or genus-based primers may require additional sequencing for a final result • Other primers are highly specific

• PCR tests must be validated separately for every sample (tissue) type accepted for testing (e.g. blood vs. CSF vs. lung)

Molecular tests available at the VMDL • West Nile virus • EHV-1/4 • Influenza A • Rotavirus A • Equine viral arteritis virus • Salmonella spp. • Lawsonia spp. • Leptospira spp.

• 16S sequencing • Mycoplasma spp. • Potomac Horse Fever • Tick panel • Borrelia, Anaplasma

• Under development:

• Coronavirus • Streptococcus equi equi • Real-time conversions 251

West Nile virus • Indications:

• Neurologic signs, especially with fever and/or with hyperesthesia or muscle fasciculations

• Appropriate samples • • • • • • •

Cerebrospinal fluid Blood in EDTA tube Brain tissue Spinal cord Spleen Lymph node Lung

• Real-time PCR • Available as standalone or as part of equine neurologic panel • Serology also available (ELISA)

Equine Herpesvirus-1/ EHV-4 • Indications:

• Neurologic signs, especially with fever • Abortion • Respiratory signs

• Appropriate samples: • Antemortem

• Nasal wash (best antemortem sample), nasal swab, conjunctival swab, tracheal wash, EDTA blood, CSF if neurologic

• Postmortem

• CSF, lung, spleen, aborted fetus (lung liver or spleen), amniotic fluid, placenta

• Single sample confirmation; no need for acute and convalescent titers • Will not determine “clearance” of organism • Herpesviruses can maintain latency in lymphoid tissue

• Conventional PCR • Available as standalone or as part of equine neurologic panel 252

Equine Influenza A • Indications:

• Fever, nasal and/or ocular discharge

• Sample types

• Antemortem: nasal wash, nasal swab • Postmortem: lung, trachea

• Single sample confirmation; no need for acute and convalescent titers • Can determine continued shedding • Conventional PCR

Rotavirus A • Indications:

• Diarrhea in foal <2 months

• Sample types:

• Feces, intestinal tissue

• Conventional PCR 253

Equine Viral Arteritis virus • Indications:

• Required export or regulatory testing • Fever, oculonasal discharge, edema, petechiation

• Sample types:

• Nasal wash/swab, blood, conjunctival swab, semen

• Positivity may have economic consequences for breeding animals • Conventional PCR

Salmonella • Indications:

• Diarrhea, fever, neutropenia

• Sample types:

• Feces, intestinal tissue

• Sometimes “too sensitive” • • • •

Detects nonviable DNA or very low shedding Positive horses may not represent a public health threat Ct may indicate approximate level of shedding Faster than culture (2-3 days vs. 3-9 days for culture)

• Conventional PCR • Available as standalone or as part of equine enteric panel

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Lawsonia • Indications:

• Diarrhea, hypoproteinemia, edema • Usually younger animals (<1yr)

• Sample types:

• Feces, intestinal tissue (ileum best)

• Conventional PCR • Available as standalone or as part of equine enteric panel • Lawsonia spp. are not amenable to culture, so serology is only alternative

• Serology indicates exposure unless acute and convalescent titers done

Leptospira • Indications: • • • •

Acute renal failure/azotemia Abortion Recurrent uveitis Hemolytic disease of neonatal foals (rare)

• Sample types:

• Antemortem

• Urine, blood (leptospiremic period quite short)

• Conventional PCR • Leptospira require cell culture to grow in lab; not oft 255

16S sequencing • Identifies bacteria that cannot be identified through routine biochemical tests or MALDI-TOF analysis • Not perfect; some genera of bacteria have nearly-identical 16S sequences • Not a real-time PCR, as PCR product must be sequenced then compared across massive databases of sequences • Generic 16S primers used to generate product

• Horses are notorious for producing bacteria that are difficult to identify, as relatively little work has been done on equine microbiome • Sample type: bacteria grown in pure culture

Mycoplasma • Indications:

• Respiratory disease, particularly pleuritis or pleuropneumonia • Feline exposure (barn cats) • Rare disease, but likely more common than documented due to lack of investigation

• Sample types: • Nasal swab

• Horses are one of the few species without a species-specific Mycoplasma • Horses can be infected with Mycoplasma felis • No data on whether M. felis can occur as a commensal

• Mycoplasmas are not often found on routine culture

• Slow-growing, fastidious, often overgrown by other bacteria

• Conventional PCR followed by sequencing

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Potomac Horse Fever • Neorickettsia risticii • Indications:

Food Animal

• Diarrhea, fever + colic, abortion, edema

• Sample types:

• Feces, EDTA blood (both preferred), intestinal tissue, aborted fetus (liver or spleen)

• Real-time PCR test • Available as standalone or as part of equine enteric panel • Serology also available (acute and convalescent needed)

“Tick panel” tests • Borrelia burgdorferi (Lyme disease) • Indications:

• Fever, shifting leg lameness, neurologic signs

• Sample types: • EDTA blood

D. Gene Luther, DVM, PhD, DACVM

Professor Emeritus • Real-time PCR test Louisiana State University • Serology available, but many horses in endemic areas have titers Baton Rouge, LA

• Titer does not indicate current infection or disease

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“Tick panel” tests • Anaplasma phagocytophilum (formerly known as Ehrlichia equi) • Indications:

• Lethargy, inappetence, pancytopenia, petechiation

• Sample types: • EDTA blood

• Real-time PCR test • More accurate than serology

• Can confirm infection vs. exposure

Tests under development • Streptococcus equi equi PCR

• Can rapidly determine shedding status • Samples: GP wash/swab, nasal swab, abscess contents • Multiple samples may be required to confirm negativity (ACVIM Consensus)

• Equine coronavirus PCR

• Coronavirus clinical signs still somewhat ill-defined • Samples: Feces, likely others

• VMDL has recently hired a research assistant professor whose tasking includes new test development and validation (Dr. Zhenyu Shen)

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Tests under development • Plan to transition all equine PCR tests to real-time format by the end of 2019 • Plan to incorporate more sample types into many tests

• Delay is often due to insufficient numbers of clinical samples available for post-test validation

Molecular tests not available at VMDL • • • • • • • • • • •

Cryptosporidium (Cornell) Coronavirus (Cornell) Equine adenovirus 1/2(Cornell) Equine rhinitis virus A/B (Cornell) Rhodococcus equi Vap PCR for virulence (Cornell) Streptococcus equi equi (Cornell) Whole-genome sequencing (Cornell) Eastern equine encephalitis (Michigan State) Equine herpesvirus-5 (Michigan State) Neospora caninum (Michigan State) MU VMDL is happy to transship your samples to other laboratories

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260

Antimicrobial resistance in equine disease Tamara Gull, DVM, PhD, DACVIM(LA), DACVPM, DACVM

Antimicrobial resistance is a growing problem in both veterinary and human medicine. Resistance is not purely a human-caused problem. Recall that most of the early antimicrobials were derived from other microorganisms, often fungi. Wild-type bacteria could develop resistance to those competing fungi even in the absence of human administration of antibiotics. However, there is abundant evidence that exogenous administration of antibiotics does contribute to resistance development. Also, cessation of antibiotic use in a population of animals results in a decrease in resistance, as there is no selection pressure for resistant organisms. We select for resistance whenever we use antibiotics, so antibiotic use should be carefully considered before administration. Antibiotics should not be given unless there is evidence of a bacterial infection, and narrow-spectrum or earlygeneration antibiotics should be used when possible. Use of more advanced or later-generation antibiotics purely for convenience is not appropriate stewardship and contributes to resistance development. Resistance may be intrinsic or acquired; it is acquired resistance about which we must be concerned. Acquired resistance typically occurs because a bacterium receives DNA from an outside source. There are three methods by which this occurs. The DNA can be from uptake of free bacterial DNA from the environment, a process called transformation. Transformation is a relatively inefficient process and intact genes are rarely acquired in this manner. DNA can also be acquired through inadvertent transfer of bacterial DNA via a bacterial virus (bacteriophage); this process is called transduction. Transduction is more efficient than transformation because the bacterial DNA is relatively protected within the viral capsid, but the amount of DNA that can be transferred is relatively small. The most efficient means of a bacterium acquiring foreign bacterial DNA is through conjugation. In this process, a bacterium that carries an F (fertility) plasmid can produce a hollow tube called a sex pilus. The sex pilus connects the donor bacterium to a recipient bacterium, and then the donor bacterium copies its F plasmid and sends it through the sex pilus to the recipient. The F plasmid may contain multiple genes, including some for resistance. Additionally, some of the donor bacteriumâ&#x20AC;&#x2122;s chromosomal DNA may also be sent through the F plasmid by accident. This method of horizontal gene transfer is by far the most effective for sharing resistance genes between bacteria. The new recipient of the F plasmid (plus whatever other genes were sent) now creates a sex pilus and continues the cycle. This means of acquisition of DNA is the most dangerous resistance-wise since a single plasmid may carry multiple resistance genes thanks to mobile genetic elements including transposons and integrons. Mutations are often blamed for causing resistance. In truth, mutations are only a minor contributor to resistance. Most mutations are silent or detrimental to bacterial survival and are not propagated. The rare beneficial mutations most commonly change a single amino acid and have relatively little impact on resistance, particularly since many types of resistance are mediated by multiple genes or even entire operons. Resistance may occur via enzymatic inactivation of an antibiotic (e.g. beta-lactamases); modification of a bacterial binding site for an antimicrobial, alteration of antimicrobial transport through porins or via efflux pumps, or by production of an alternative target. Any bacterium may possess one or more of these resistance mechanisms although some are more common in specific genera of bacteria than others. Regardless of the method employed, most are specific to one class of antimicrobials. But

261

again, one bacterium can easily harbor multiple resistance genes and each gene carries a specific resistance mechanism against a specific class of drug. Equine practitioners have been fortunate with regard to antimicrobial resistance as compared to livestock practitioners. The common practices of subtherapeutic antimicrobial use for growth promotion and mass prophylaxis or metaphylaxis have resulted in a great deal of resistance in many livestock species; some antibiotics have been restricted or removed from livestock practice because of this resistance development. Horses are seldom medicated in this manner and have mostly been spared the wholesale development of resistance. However, some equine pathogens have shown increasing resistance trends even if the reason behind those changes are unclear. Streptococcal organisms remain highly susceptible to beta-lactams in vitro despite heavy use of depot ceftiofur. Conversely, staphylococci are highly variable in their resistance patterns, plus there is the concern about methicillinresistant staphylococcal isolates. Many equine organisms have become resistant to trimethoprim-sulfa combinations. This is likely to have resulted from a combination of heavy and relatively indiscriminate use and an issue with inappropriate labeling on some potentiated sulfa products. Some sulfas are labeled for once-daily use even though equine pharmacokinetics shows that twice-daily use of these time-dependent drugs is necessary to maintain concentrations above bacterial MICs for >40% of the time. The balance of this talk will discuss specific equine pathogens and the common resistance patterns seen in each, plus any indications of changing resistance patterns over the past 5 years in samples submitted to the VMDL. Slides will be made available at the MVMA meeting but are presently still under data analysis.

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Equine

Martha Scharf, DVM, DAVP

Equine Ambulatory Veterinarian - MU-CVM Equine Clinic University of Missouri - College of Veterinary Medicine Columbia, Missouri

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EQUINE WOUNDS – IMPROVING INITIAL ASSESSMENT AND FIELD MANAGEMENT

EQUINE WOUNDS

MARTHA SCHARF, DVM, DABVP (EQUINE PRACTICE), IVCA CERTIFIED

 Equine wounds affects approximately 25% of the US horse population annually 

Most horses have at least 2 serious injuries in their life



Large portion of equine field emergencies



Up to 10% of emergency admissions at referral centers

EQUINE WOUNDS  Horses are efficient healers 

Strong inflammatory reaction



Efficient contraction



Rarely self-traumatize

until they’re not… 

Limited soft-tissue coverage of distal limbs



Involvement of synovial structures



Excessive movement



Exuberant granulation tissue



Heavy contamination

 Most equine practitioners quickly develop a comfort with wounds 

Even though we’re all doing it differently….

 So, what matters and what doesn’t?

TIME

INITIAL ASSESSMENT

 Golden period - 6-8 hours?

 Examine horse for complications



Time necessary for contaminating bacteria to multiply to 105 per gram of tissue 



Blood loss



Contamination of body cavities



Lameness, synovial fluid leakage

Affected by blood supply, head versus limbs

Contamination  infection



 Many studies do not show a significant influence of time on prognosis 

Affects cost and cosmesis



Synovial contamination – some data supporting differences at 36 hours and 10 days



Should treat aggressively and promptly once involved



HR >80 bpm, pale mucous membranes, prolonged CRT, weak pulse, cold extremities, PCV <25%

Dyspnea, RR >40 brpm, hemorrhagic/frothy nasal discharge, abdominal fluid leakage, dark mucous membranes, HR >80 bpm

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WOUND CLEANSING

CLIPPING

 Gross debris removed by saline, tap water, or dilute antiseptic  Tap water 



Most practical option for extreme wound contamination 

Non-sterile



Hypotonic

Human studies 

Local cellular swelling, cellular damage



No difference in persistent wound contamination or healing rates

 Clipping of hair – 40 clipper blade or disposable safety razor 

Significant decontamination



Ease of examination and repair



Minimize future accumulation

ANTISEPTICS

POVIDONE IODINE

 Solutions

 Broad spectrum of action



Chlorhexidine diacetate (CHD) 2%



Povidone Iodine 10%

 Scrubs



Minimal resistance

 4-6 hour duration of efficacy 

Inactivated by organic material and blood



Chlorhexidine gluconate (CHG) 4%, 2%

 MOA: penetrate bacterial cell wall, replace intracellular molecules with free iodine



Povidone Iodine 10%, 7.5%

 Skin reactions – subcutaneous edema, skin wheal formation

POVIDONE IODINE

CHLORHEXIDINE

 Broad spectrum of action  Dilution to 0.1-0.2%  10-20 ml of 10% solution per liter of crystalloid 

Minimizes cytotoxicity



Increases bactericidal action of free iodine



Higher concentrations inhibit WBC viability and migration, reduce fibroblast proliferation, and desiccate tissue



Inherent resistance from Proteus spp, Pseudomonas spp, most fungi, select viruses

 Prolonged duration of efficacy 

Binds to stratum corneum of epidermis, kills bacteria from sebaceous and sweat glands



Inactivated by alcohol, maintains in organic material

 MOA: cation binds to negatively charged bacteria cells walls,  Toxicity – corneal ulceration, synovitis

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Food Animal

CHLORHEXIDINE

SCRUB PRODUCTS

 Beneficial in areas oily or sebaceous contamination 

Skin surrounding wound edge

 Local cytotoxic effects on wound beds  Dilution to 0.05%  25 ml of 2% solution per liter of crystalloid

 Superior mechanical removal of debris to solutions



Bacteriostatic at low concentrations, bactericidal at high concentrations



High concentrations result in cytotoxity



Precipitates in saline



CHG > CHD and PI solution and scrub 

PI scrub is largely ineffective at reducing bacterial loads in wounds

 Rinse

ANTISEPTICS



Alcohol may potentiate PI scrub, inactivates CHD & CHG, cytotoxicity



Saline appropriate for all

IRRIGATION  Recommended in all wounds – adherence of electrostatic and exudative bacteria

 Povidone-iodine and chlorhexidine formulations function via contact time 



Do not require manual removal of bacteria



With one 5 minute scrub, CHG + NaCl out performs: 

CHG + ROH



PI + NaCl



CHG + ROH

Physically degrades biofilm

 Most effective at oblique angle

 Significant reduction of bacteria with 10 minute, 5 minute, 3x 30 seconds, and 2x 5 minutes



Constant or pulsating jet

 10-15 PSI are 80% effective at bacteria removal 

Debridement improves up to 70 PSI



Detrimental fluid dispersion into tissue at > 20 PSI

 50-60 cc syringe, 19 gauge needle OR spray bottle

WOUND DECONTAMINATION

1. Clean gross debris with water or saline 2. Clip 3. Cleanse wound with CHD and pack with gauze if possible 4. Scrub surrounding skin with CHG, rinse with NaCl 

If necessary, add:

WOUND EXPLORATION

Delbert G. Miles, DVM, MS  Digital – sterile gloves 

MRSA

Veterinary Research & Consulting Services, LLC Greeley, CO  Sterile Probe 

± Radiographs

 Synovial Involvement

Irrigation with dilute CHG



Anatomy knowledge

Debridement



Diagnostic arthrocentesis

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TREATMENT

TREATMENT  Closure

 Reasons to consider hospitalization



Primary



Synovial contamination



Delayed Primary



Bone damage



Secondary



Tendon and ligament damage



Hoof instability



Infection or contamination



Body cavity penetration



Large cavities



Significant pain or infection



Tension



Need for drainage

LOCAL ANESTHESIA

 Reasons to avoid closure

DEBRIDEMENT

 Lidocaine, mepivacaine, bupivacaine 

Na channel blockers

 Purpose:

 Perineural



Reduce bacterial load

 Local infiltration



Remove wound contaminants (fibrin, biofilm, dead tissue, organic debris)



Improve vascular supply



Cytotoxicity

 Intrasynovial

 Sharp or blunt  CO2 laser, hydrosurgical instrument, enzymatic, chemical dressings

 Toxicity 10 mg/kg – 250 ml of 2% lidocaine in 500 kg horse

PRIMARY CLOSURE 

Fresh, minimally contaminated wounds



Good blood supply



No involvement of vital structures



Head wounds



Skin flaps



Upper body wounds



Superior cosmesis and healing times



Temporary biological band aid

DELAYED PRIMARY CLOSURE

 Delayed 4-5 days, closed before formation of granulation tissue 

Literature is inconclusive on timing and benefit of delay

 Severely contamination  Marked contusion  Swollen wounds  Wounds involving a synovial structure

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SECONDARY CLOSURE

SUTURING

 Choice of suture material

 Closure over a granulation tissue bed

 Chronic wounds

 Compromised blood supply

SUTURING



Microcirculation

Muscle with fascial layer

 Tissue loss  Areas of high motion

Interrupted vs continuous Edema

Skin



 Deep wounds

Loosely approximately wounds are stronger at 7, 10, and 21 days then tightly secured ones



 Large wounds

Account for skin swelling



Absorbable

SECOND INTENTION HEALING

 Patterns 

Monofilament



 Layers of closure

 Severe contamination or infection



 Significant infection

Tension sutures

 Slowest and least cosmetic

 Removal – 10-14 days

 Extensive and weak scarring

PHASES OF WOUND HEALING

1. Inflammation

INFLAMMATION  Clears foreign material and dead tissue  Vascular and cellular response  Injury to endothelium → cytokine response

2. Proliferation



Vasoconstriction → vasodilation



Platelet scaffold



Fibrinocellular clot dehydrates superficially to form a scab

 Cellular debridement via neutrophils, macrophages, and enzymes

3. Remodeling

 Peaks at 1-2 days

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PROLIFERATION 

12 + hours



Granulation Tissue



PROLIFERATION

Cells migrate along fibrin lattice

 Angiogenesis



Macrophages



Fibroblasts



Response to tissue injury and hypoxia



Endothelial cells



Endothelial cell migration

Purposes 

Scaffold for epithelial migration



Infection resistance



Collagen production → strength



Wound contraction

PROLIFERATION

REMODELING 



Myofibroblasts, ECM, cytokines, GFs



Lag phase

Migrate from periphery (0.1-2 mm/day)



Fast contraction

Migrate under scab until like cells are contacted



Slow contraction

 Epithelialization  

 Can be slowed by infection, proud flesh, bandage changes, desiccation, decreased oxygen tension 

Wound Contraction



Accelerated by growth factors, topical antimicrobials, and semiocclusive dressings



BANDAGING

Collagen Remodeling Granulation tissue to scar tissue ↑ Organization 

Larger bundles



Cross-linking

6 days – 2 years

BANDAGING

 Protect from contamination  Reduction in edema  Absorption of exudate  Maintain warmth and reduce CO2 loss  pH  Immobilize and reduce trauma

 Bandage change q 1-7 days 

Clean and assess at each bandage change

 Alleviate pain  Reduce healing time by 30-50%

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TOPICALS

TRIPLE ANTIBIOTIC OINTMENT

 Bacitracin, Polymixin B, Neomycin  Over 2500 wound dressings on the market

 Wide spectrum of action Ineffective against Pseudomonas spp.



Can lead to iatrogenic damage by owners



Powders, desiccants

 The Zn in bacitracin stimulates epithelization by 25%



Scald

 Poorly absorbed



Adhesion of organic debris



Not good for deep infection

 Oil-based

SILVER

 Ionic silver is antimicrobial against Pseudomonas spp, Staphylococcus spp, E. coli, yeasts, fungi, etc, 

Inhibits DNA replication and subsequent protein synthesis



Moisture is required for release of silver ions

 Epithelization effects? 

Increased by 28%? Or decreased due to fragility? Aided by Aloe Vera?

 Water-soluble cream absorbs well, cleanses well

 Good G+ and G- spectrum 

Ineffective against Pseudomonas spp.

 Furacin delays healing by 24%  Promotes granulation tissue formation  Wear gloves!

HONEY

SYSTEMIC ANTIMICROBIALS

 Topical antimicrobial and debriding agent



Used with most repairs



Areas of heavy contamination



Trimethoprim Sulfa – 20 mg/kg PO BID



Penicillin – 22,000 IU/kg IV/IM QID & Gentamicin – 6.6 mg/kg IV SID



Ceftiofur sodium – 2.2 mg/kg IV/IM BID



Glucose oxidase from bees  low level release of H2O2  cellular proliferation via antioxidant effect



Low pH, high sugar  debridement and anti-inflammatory



Osmotic (poultice-like) effect for plasma, chemoattractant for macrophages, angioblasts, and fibroblasts

 Enhances and regulates granulation tissue formation and epilelization  Manuka Honey 

Superior and sustained anti-microbial effect



Enrofloxacin – 7.5-10 mg/kg PO SID



Less fluid draw, less dilution



Chloramphenicol – 25 mg/kg IV/IM, 50 mg/kg PO TID-QID



UMF (Unique Manuka Factor) ≥ 10 is effective against Pesudomonas spp, MRSA, E. coli, yeasts, fungi 

Ceftiofur crystalline free – 6.6 mg/kg IM, 2 doses 4 days apart



NITROFURAZONE OINTMENT

Medical grade – filtered for wax and debris, gamma sterilized for maintenance of glucose oxidase with out clostridium spores

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NSAIDS

TETANUS PROPHYLAXIS

 Inflammation is a decontaminating stage of wound healing 

Can be prolonged by contamination



Wound healing in horses vs ponies

 Evidence suggests efficacy >1 year 

 NSAIDs inhibit cyclooxygenase 1 and 2 enzymes  Short term administration has a negative impact on healing

Serum titers have not yet been validated as evidence of protection

 Anti-toxin – administration of 1500 IU



Decrease number of fibroblasts, weakened wound breaking strength, reduced wound contraction, delayed epithelialization, impaired angiogenesis

to an unprotected horse may provide 2-3 weeks of protection (AAEP)



Long term?



True challenge studies are lacking



Efficacy has been questioned (Dennis, S; Aust Vet J, 2014)

 Administer as needed for pain and swelling

AFTER CARE

QUESTIONS?

 Keep clean and moist  Monitor for infection, pain, lameness, proud flesh  Re-evaluate as necessary

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EQUINE WOUNDS – TECHNIQUES FOR MANAGEMENT OF DISTAL LIMB WOUNDS

INTENSIVE MANAGEMENT/REFERRAL

MARTHA SCHARF, DVM, DABVP (EQUINE PRACTICE), IVCA CERTIFIED

 Reasons to consider hospitalization or intensive

management 

Synovial contamination



Synovial Lavage



Bone damage



Regional Limb Perfusion



Tendon and ligament damage

Foot Casts



Hoof instability



Body cavity penetration



Significant pain or infection

 Intensive Field Management of Distal Limb Wounds



DIAGNOSIS OF SEPTIC JOINTS

 Remember, prompt treatment ideal but aggressive, appropriate treatment is better

DIAGNOSTIC ARTHROCENTESIS

DIAGNOSIS OF SEPTIC JOINTS



Edema, contamination



Proper assistance, environment



Data supports differences in prognosis at 36 hours and 10 days

SITE PREPARATION  Clipping not necessary for arthrocentesis site

 Diagnostic arthrocentesis

 Anatomy is not always a good guide



Flexion versus extension



Blunt trauma can erode into joints



Can clip for visualization or decontamination



Small increase in translocation of material when clipped

 Scrub 

CHG + ROH



7 minutes



Alcohol prevents synovitis by deactivating CHG



(10 minute, 5 minute, 3x 30 seconds, and 2x 5 minutes)

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ARTHROCENTESIS

SYNOVIAL FLUID

 Sterile gloves  Sedation 

Twitch

 Wrap tail if necessary

 Save a synovial fluid for cytology and culture 

Chronic wounds have sealed, easy to collect



May not be possible in acute wounds

 Remote site 

Avoid edema and contamination

SYNOVIAL FLUID 



PRESSURIZE JOINT  Pressurize with syringe or 3 way stop-cock system

TP 

< 2 g/dL in normal joints



4-6 g/dL with inflammation and infection

TNCC 

<1.0 x109/L (1,000/µL) in normal joints



> 30 x109/L (30,000/µL) indicates sepsis



< 15 x109/L (15,000/µL) in healthy post-operative joints

Neutrophils 

<10% in normal joints



Often >80% in septic joints



Approximate volume of joint



Back pressure



Visualization of egress



Disconnect and allow for egress through needle

10:1 PPG can aid in visualization

 Fluid 

Color, viscosity, turbidity, froth

LRS or saline 

Buffer



Balanced electrolytes

LAVAGE JOINT

 Egress

 Volume ≥ 1 L



Wound



Patient compliance



Second needle site



SQ accumulation of fluid



Synovitis

 Closed fluid drip system 

Gravity flow



Pressure bag



3 way stop-cock 

Attached to: 1. Extension set + needle in joint

 Until clear and dilute

 IA antibiotics – 150-500 mg of amikacin 

150 mg of gentamicin

2. 10 ml syringe 3. 1 L of LRS/saline

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LAVAGE JOINT

ANTIBIOTIC THERAPY 

Systemic 

K+ penicillin – 22,000 IU/kg IV QID



Procaine penicillin – 22,000 IU/kg IM BID



Gentamicin – 6.6 mg/kg IV SID



TMS – 15-30 mg/kg PO BID



Adjust as indicated by culture



Mean duration of 4-6 weeks

OR AND

 Repeat q1-3 days as necessary to achieve decontamination 

Clinical signs



Synovial fluid analysis



Visualization of gross contamination



13 days following arthroscopy

Intraarticular 

6x higher than RLP for approximately 24 hours (initially 800x)



150-500 mg of amikacin



150 mg of gentamicin



90% effective against equine isolates

85% effective against equine isolates

IV REGIONAL LIMB PERFUSIONS

 Concentrated deposition of antibiotics

REGIONAL LIMB PERFUSIONS

 Decreased cost of medication  Minimize toxicity  Decreases development of resistance

Orsini, Clin Tech Eq Prac, 2004

DOSE

ANTIBIOTIC CHOICE 

Bactericidal are superior to bacteriostatic 

 1/3 of systemic dose diluted to 30-60 ml for distal limb, injected over a period of 5-15 minutes with tourniquet

left on for 30 minutes 

Auer & Stick, 4th ed.



Bactericidal 

Aminoglycosides



Penicillin



Cephalosporins



Metronidazole



Rifampin



Quinolones

Bacteriostatic 

Chloramphenicol



Tetracyclines



Sulfonamides



Macrolides

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ANTIBIOTIC DOSE 

Concentration-dependent antibiotics primarily 

A single dose of antibiotic can be effective against susceptible bacteria 



PERFUSED VOLUME

Reach ≥ 55x MIC IA



Amikacin 500-1000 mg, 2000-2500 mg



Gentamicin – 100-300 mg, 500 mg



Imipenem – 250 mg



Penicillin – 10-20 million IU



Ceftiofur – 2 g



Ceftaxime – 500 mg



Enrofloxacin – 700 mg

Low Volume High versus…

Enrofloxacin  significant vasculitis

REGIONAL LIMB PERFUSIONS

TOURNIQUET

 Regional anesthesia if possible

 Tourniquet Placement



Distal limb



Esmarch or pneumatic

 Sedate



Adhesive tape or bandage used to secure the esmarch

 Clip and scrub



Elastikon for traction if necessary

 Topical lidocaine, prilocaine

 Can use roll gauze to specifically occlude vessels

 Topical liposomal1% diclofenac cream



Mid-metacarpal/tarsal region for palmar/plantar digital vein

Reduces post-injection swelling



Distal radius/tibia for cephalic/saphenous vein



DISTAL LIMB PLACEMENT

DISTAL LIMB TOURNIQUET

Orsini, Clin Tech Eq Prac, 2004

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DISTAL LIMB TOURNIQUET

PROXIMAL FORELIMB TOURNIQUET

PROXIMAL HINDLIMB TOURNIQUET

Orsini, Clin Tech Eq Prac, 2004 Orsini, Clin Tech Eq Prac, 2004

PROXIMAL LIMB TOURNIQUET

CATHETER

 25-27 ga butterfly catheters 

Allow blood to flow until slowed to a drip, or aspirate volume of infusion

 20 gauge, 1 inch catheter can be used proximally if preferred

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BUTTERFLY CATHETER

IV CATHETER

INFUSION

SLOW FLUSH

 Infuse antibiotics  Slowly flush with 10-60 ml of saline

30 MINUTE ACTION

 Tie knot in tubing  Tape in place

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AFTER-CARE

 Hemostasis bandage after perfusion  Monitor injection site, tourniquet site,

distal limb, wound site

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COMPLICATIONS

 Loss of venous access  Intra-arterial injection  Localized edema  Vasculitis

FOOT CASTS

 Improve outcome

 Indications:

 Accelerate wound healing  Decrease duration of healing  Decrease cost of healing

 Provide stability  Protection



In heel bulb and hoof lacerations



Following hoof surgery



Management of P3 fractures



Severe desmitis of DIP collateral ligaments

 Do not apply over heavy contamination or necrosis 

Delay if necessary

FOOT PREPARATION

PRIMARY DRESSING

 Remove shoe

 Wound topical

 Clean and pare out foot

 Telfa  White gauze

 Scrub foot free to debris 

 Elastikon

Surgery hand scrub brushes

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STOCKINET

FELT PADDING

 5 cm synthetic cast stockinet 

 5 cm strip of orthopedic cast felt wrapped around

Cut to twice the length of the distance from the bottom of the hoof to mid-cannon

proximal limit of intended cast

 Rolled onto limb with one end at mid-cannon 

Middle twisted under hoof



Free end rolled back over the first layer up to midcannon



Proximal pastern



Coronary band

 Secured with white tape

Ketzner, KM, Aust Vet J, 2009

FELT PADDING

Ketzner, KM, Aust Vet J, 2009

GIGLI WIRE

 Thread gigli wire through IV drip set tubing (with ends cut off)  2-3 inch cast padding 



CASTING TAPE

Immerse in room temperature to mildly warm water



Spiral over padding with 50% overlap

 Standing 

Apply on weigh bearing limb



Then lift to wrap toe with minimal flexion



 5 cured layers

Allow to cure weight bearing 

Ketzner, KM, Aust Vet J, 2009

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White adhesive tape

CASTING TAPE

 3 inch fiberglass casting tape 

Extra 20 cm of wire at each end

 Tape gigli wire in tubing in place across the mid-sole then up the medial and lateral sides of the limb

Roll on evenly from distal hoof wall to the distal half of the felt strip

Toe on block

Ketzner, KM, Aust Vet J, 2009

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CURING

CAST  Following curing:

 Acrylic can be applied to the sole for traction and

 Anesthetized 

Wrap in simulated weight bearing position



Wooden board can be applied to the sole of the extended limb to simulate weight bearing

durability

Ketzner, KM, Aust Vet J, 2009



Aluminum cast tape wrapper can be added for extra durability



Elastikon added for traction

 Elastikon applied at the top to prevent foreign

material in the cast Ketzner, KM, Aust Vet J, 2009

DURATION

 Change or remove every 10-15 days 

 Can also be limited to below coronary band

COMPLICATIONS

Gigli wire or cast cutters

 Heel bulb laceration in casts 

2.8 ± 1 weeks vs 4.1 ± 1.3 weeks (Janicek, 2005)



2.5 ± 0.8 weeks (Ketzner, 2009)

COMPLICATIONS  Cartilage degeneration and capsular fibrosis

 Cast sores 

13% in foot casts (vs 52% in traditional casts)



Heel bulb, proximopalmar aspect of the cast



Average of 12 days after application



Tend to be minor



Monitor for lameness, heat, drainage



Prevent by curing in weight bearing position, avoiding over padding



Chronic lameness and decreased range of motion



Restriction of movement of cast



Prevented by gradual, controlled exercise – hand grazing, stall movement, weight bearing

 Other 

Breakage of cast



Osteopenia



Fracture due to limited ROM



Tendon damage



Ligament avulsion

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PROUD FLESH

FIELD MANAGMENT

 Bandaging typically exacerbates proud flesh 

Hoof casts are generally an exception!

 High temperature, moist environment, high carbon dioxide 

Acidified wound



Decreased oxygen concentration (further released from hemoglobin due to low pH)



Oxygen gradient stimulates angiogenesis, dermal fibroblast production, and granulation tissue formation

 Moist exudate can further inflammation

 Complicated distal limb wounds, consider referral 

But, try field management if possible



Should be prompt, aggressive



Harder to pursue gold standard later

 Warn owners of possible complications

 Friction

QUESTIONS?

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Science On the Forefront

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Science On the Forefront

Kevin Cummings, PhD

Associate Professor University of Missouri - College of Veterinary Medicine Columbia, Missouri

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Key Points: • An understanding of respiratory physiology o Acid-base balance o Gas exchange and transport o Central and peripheral control mechanisms • An understanding of anesthetic machine function is necessary to interpret a capnograph • A time capnograph is used to estimate arterial carbon dioxide partial pressure, and it can also provide information on o inspired carbon dioxide partial pressure o respiratory rate o endotracheal tube placement o cardiovascular function o anesthetic machine function o gas exchange • Capnogaphy is particularly useful as a monitor of effective circulation during CPR

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Science On the Forefront

Marc Markway, DVM

Markway Veterinary Service Eldon, Missouri

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Use of Class 4 Laser Therapy in an Equine and Small Animal Practice presented by Marc Markway, DVM – Markway Veterinary Service, Eldon, Missouri This presentation is from a practitioner’s view of approximately 240 patients having received a collective 1,400 treatments. These treatments ranged from post-surgical to chronic, long-term (1 year +) injuries or conditions. Currently, laser therapy is being used worldwide, but North America and the U.S. has been slower to adopt this technology. This is because laser therapy was developed in Eastern Europe in the 1970s and spread from there. The North American Association for Laser Therapy (NAALT) was established in 1998 and includes the U.S., Canada and Mexico. The term LASER is an acronym for Light Amplification by Stimulated Emission of Radiation During the 2005 NAALT Conference, the industry settled on the term “photobiomodulation therapy” which is a technical term for Low Level Laser Therapy. It is a light therapy using lasers or LEDs to improve tissue repair, and reduce pain and inflammation wherever the beam is applied. There are only two types of lasers in healthcare: • Surgical – cut • Therapeutic – heal There are four laser classifications: • Class I – Cannot, under normal operating conditions, cause any biological tissue damage. Examples are CD players, laser printers and, now, some therapy lasers. There currently are some Class I Therapy lasers on the market.

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• Class II – Have potential for optical hazard if viewed directly for long periods of time. Bar code scanners and laser pointers and levels are examples. • Class III – Medium power and require control measures to prevent viewing of the direct beam. Examples are research lasers and LED units and some therapy lasers. • Class IV – Have an output power greater than 500 mW (1/2 a Watt). In healthcare professions these are divided into surgical and therapeutic. Class IV lasers are capable of causing eye injury, regardless of direct exposure to the beam or reflecting off a surface. For this presentation, we are going to refer to Class IV, as that is what we have in our practice. How laser therapy works: Simplified, the light waves produced by laser therapy stimulate the mitochondria of the cells thereby increasing cellular activity and reducing inflammatory substances and pain. Laser therapy is used to: 1) 2) 3) 4) 5)

Increase the speed, quality and tensile strength of tissue repair Provide pain relief Reduce inflammation Improve function of damaged nerve tissue As an alternative to acupuncture needles

We started using Class IV laser therapy in December 2015 because I felt there was overwhelming anecdotal evidence that it worked. Since then, we have used it on a variety of equine and small animal applications with excellent results. How to adapt laser therapy to your practice: 1) Get everyone on board – you have to believe in it and use it. It is not voodoo or placebo effect. It works.

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2) Change your thought process – would laser help this condition? Consider it in any and all musculoskeletal injuries or conditions. Keep an open mind. If you think it might help, it probably will. 3) Charges – keep affordable because of multiple treatments needed. Treatments can be administered by techs. Applications in practice: 1) 2) 3) 4) 5)

Any injury … period! Chronic scar tissue Orthopedics Post-surgery Acupuncture

General protocols of use: 1) Eye protection for all in the room—vet/tech, client and pet. 2) Keep wand moving in grid pattern, pay attention to what you are doing to avoid burns. We have not had one to date. 3) We usually use the highest wattage recommended with the least amount of time. There is some anecdotal evidence that higher power speeds healing, but consider coat and skin color as dark colors absorb more heat. Most equine ligament and tendon injuries I treat at 15 watts for 4-5 minutes; I treat backs longer. Frequency of treatment: 1) Tendon and ligament injuries in horses: Usually 3X/week for 3-4 weeks. 2) Arthritic conditions in old dogs: 3X/week for 2 weeks, then once a week for 2-4 weeks then once every 2 weeks then once a month. Adjust frequency to dog’s response. 3) Many acute muscle injuries only need 1-3 treatments. When I started using the laser, I used it with little (one dose) or no NSAIDs or steroids. I found that it quickly relieved pain without drugs and I rarely use them.

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We do use antibiotics for open wounds or punctures. I also measured chronic conditions with calipers and tape measure to verify reduction in scar tissue. We also found that use of the laser improved our diagnostics. We try to determine the specific area that needs treatment to reduce treatment area size, thereby reducing the time of treatments, and to improve our results. Our laser is programmed for different weight, body condition, color of skin and color and length of coat in small animals. It is pretty user-friendly. In my opinion, laser therapy is the best long-term treatment for muscular tendon and ligament injuries in my 47+ years of practice. We have had remarkable results with equine ligament and tendon injuries. Here is a cross section of cases. Case Presentations • Case 1 – Hancock, 12 y/o AQHA gelding head horse, presented 12/12/15 cut on right rear palmar surface of fetlock involving DDF sheath, grade 3 lame. Rx Penicillin/Gentocin 5 days, plus laser therapy 3X/week for 2 weeks. Sent home, much improved. One week later condition worsened. Laser treatment 3X/week for 2 weeks; sent home sound. One year later still sound. • Case 2 – Buttercup, 13 y/o APHA mare, laceration right rear flexor tendon pastern area 3 weeks duration. Non weight bearing; two draining wounds at sesamoids. Rx Penicillin/Gentocin 5 days, plus laser therapy 3X/week for 2 weeks. Sent home 90% sound; animal was 100% sound within a short time after and has been since. • Case 3 – Carly, 14 y/o Yellow Lab, 96 pounds, started laser therapy 6/16/18 for arthritic hips. She has continued treatments through this year, was off Carprofen for almost a year. • Case 4 – Sparky, 10 y/o AQHA calf roping gelding, complaint of not stopping good. Exam showed no lameness at trot. No response to hoof testers or flexion test. I suggested laser treatment of hocks and stifles, after which to lay off 3-5 days. Three days later, owner saddles horse as usual, same

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routine of warm-up and started to rope calves on him. Owner said he was a new horse. Other people who knew the horse asked him what he did to the horse to get him stopping so good again. I treated him 5 days after first treatment and he has been sound since I last saw a year ago (19 months after treated). • Case 5 – Star, 13y/o Standardbred driving horse. Fell 1 year prior and rested 9 months, gets lame after 4-5 mile drive. On exam, grade 1 lame right fore. No improvement with abaxial nerve blocks, but much improved with high 4-point block. The right high suspensory area was 3mm thicker than left, two fingers width below accessory carpal bone. Treated 3X/week for 4 weeks. Sent home sound with instructions to start him slowly for two weeks. I called owner every two weeks to see how doing. Answer was always “I think he’s sound”. Eight weeks out his answer was “we drove him 15 miles yesterday, and he’s not lame”. Six months later, they thought he was a little lame, but they had let his feet get long. When they brought him in a few days later after a hoof trim, he was already better, but I gave him another treatment. • Case 6 – Gilly, 7 y/o female Airdale, presented 3/15/16. Rubbing head, cries sometimes; some mornings whines every step, moves slowly. Going on for some time; ears and teeth normal. Administered and dispensed Carprofen. o 3/25, 9am, extremely painful to move head or neck. Radiograph reveals narrowing of C4-C5 space, suspect bulging disc. Cannot bend head and neck to eat or drink. Applied laser therapy to affected area. By 3pm, could eat and drink normally. o 3/26, 7:30am, she was eating, drinking, wagging tail, moving fluidly, still whined when shook her head, but was greatly improved. o 3/27, jumping around, wagging tail. o 3/28, much improved, no whining—in effect, normal. When owners picked her up they said it was a miracle! I advised she would probably need retreating. o 4/5 retreated, little stiff in front. o Good until 8/17/16, when a little stiff again.

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• Case 7 – Pep, 11 y/o cutting mare went lame in rear during a cutting contest. Exam showed grade 1 lame left rear, not loading left rear, and edema over sacroiliac. Told owner mare may take several treatments, as he wanted to show her in two weeks. The day after the first treatment, the mare trotted off sound. We treated her three times and she was sound until a fore leg lameness sidelined her several months later and she was retired as a brood mare. • Case 8 – Annie, 3 y/o APHA pleasure show mare presented December 2017. Left rear suspensory enlarged proximally, grade 2 lame. Several months duration. Was going to have surgery, but was referred by another client of ours to try laser. Treated 3X/week for four weeks and was sent home sound. Recommended starting her easy in two weeks; they waited longer, but mare was back in full training by May 1 and was still sound in August when I checked with owner. • Case 9 – Max, 4 y/o male Dachshund presented 7/14/16 for exam. While owner was moving, Max got stepped on and was paralyzed in rear end. Given steroids by another vet and doing swim therapy. Has been holding urine the last 5 days; has withdrawal reflex. Treated with laser—both coxofemoral joints and lumbar/sacral spine. On 7/18/16 already noted improvement. Owner says standing and wagging tail. On 8/4/16 after six treatments owner said Max walked up long driveway yesterday, doing good. On 8/18/16 after three more treatments Max squatted to defecate. Last treatment was 8/25/16. Max went back home to Arkansas. • Case 10 – Cracker, 15 y/o barrel and pole gelding, abscessed tooth at one time, developed a granuloma in left nostril. I surgically removed it, but there was a lot of facial distortion and a draining tract into the sinus. About four years after surgery, his left airway was a quarter the aperture of right. The laser was new to me, and I suggested trying it for at least three treatments. By the third treatment, the airway was open almost as far as the right normal side. During barrel racing season, we treated him every 2-3 weeks, and he still is winning. His owner wanted to try it on his stifles and

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hocks as he was getting a little crampy, handling them and shoeing him. After three treatments, owner said he’s the best he’s been in two years. • Case 11 – Chic, 2 y/o AQHA filly, reiner in training for futurities, presented 6/15/18. Right fore high suspensory injury. Was recommended shock wave therapy or nine months stall rest. Owner called and asked about laser therapy. I told him we have excellent results with suspensory injuries. We treated her 3X/week for four weeks; told trainer to bring her back easy. Two weeks after laser therapy she was back in training and still is sound six months later. • Case 12 – Rooster, 12 y/o AQHA gelding, roping head horse, presented 11/12/18. Puncture medial left hock. Owner was gone a week and came home to draining puncture and three-legged horse. I was out of town, but referred to another veterinarian. Diagnosis was torn capsule of hock with poor prognosis; advised surgery with guarded prognosis. The owner couldn’t afford surgery and brought horse to my practice when I got home. The original veterinarian cultured the lesion and sent horse home on Gentamycin and Penicillin. Meanwhile, we started the horse on laser therapy and continued the antibiotics. The culture results were negative, but finished the antibiotics. After 4 weeks of therapy 3X/week, the horse was sent home with a grade 1 lameness at trot. The owner was told to walk the horse daily and keep him in a large pen where he could exercise himself. The horse has continued to improve as of 12/19/18. • Case 13 – J-Lo, 9 y/o AQHA barrel mare presented 10/8/18. Grade 3 lameness on right fore in pasture. Diagnosis, tear of the lateral branch of right fore suspensory ligament at its attachment to the sesamoid. Treated with laser 3X/week for 4 weeks. Sent home with grade 1 lameness at a trot after trotting for a few minutes. Told owner to keep in small pen where she could exercise herself some and to hand walk her. She continued to improve, and as of 12/21/18, they were starting to exercise her again. • Case 14 – Mocha, 10y/o AQHA gelding trail horse. Presented 10/2/17 with chronic sore back, cinchy, tender to touch at times. Treated 3X in one week,

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and owner took home; said much improved. Seven weeks later, we treated 3X more; horse has been good ever since. The owner told me they horse couldnâ&#x20AC;&#x2122;t swim when we started treatment the first time, but now swims and has no back issues at all. We have treated several equine tendon injuries with great results. After treatment of stifles and hocks, people have told us the horse is moving the best he/she has in some time, sometimes the best in years! We have treated shoulder and stifle injuries in dogs with good success, with one dog returning to working competition in two weeks. Questions and Discussions

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Science On the Forefront

Brandon Ames, CEO

Chief Executive Officer - AniCell BioTech Chandler, Arizona

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Amnion FAQ: Top 10 Things You Should Know About the Latest in Regenerative Treatments. Presented by:

Brandon Ames, CEO

Disclosure (COI) • CEO and Founder of AniCell BioTech

Q1 What is a Regenerative Treatment? Regenerative medicine is … Regenerative Medicine, 2008. New Branch of Medicine – Relatively Promotes repair, regrowth and regeneration of healthy tissue and bone in conformationally compromised areas. Regeneration is attained by mechanical artificial stimulation or by using biological material to augment what the body cannot do naturally. Often regenerative treatments are able to accelerate tissue regeneration or better quality tissue.

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Q2 What are the latest of regenerative therapies? There are many forms of regenerative treatments such as concentration, in vitro growth, banking, stimulation, or collection. Concentration/Agent Reaction PRP, IRAP

In Vitro Growth

Adipose, Bone Marrow, Dental Pulp, Umbilical Cells

Banking

Umbilical Cord Blood

Mechanical Stimulation

Shockwave, Low Light/Cold Laser, Ultrasound

Manipulation

Chiropractic and acupuncture

Collection Amnion

Q3 What is amnion and where does it come from? Amnion is the innermost membrane that contains the newborn of a mammal, reptile, or bird prior to birth. Amnion – Membrane & liquid that surrounds newborns Contains all the basic building blocks of tissue & bone. Responsible for the single greatest growth spurt in an animals life. Amnion is immune privileged Amnion is the miracle of Child Birth

Major “Structural” Components of Amnion Cells

Mesenchymal (AMSC) Epithelial cells (AECs)

BioScaffold or Basic Building Blocks of Extracellular Matrix Cytokines/Growth factors

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ExtraCellular Matrix: Substrates in Amnion

— Niknejad H, et al. Eur Cell Mater. 2008;15:88-99.

Equine

Messengers Role in Tissue Healing Cascade • Stimulate cell migration, proliferation and differentiation • Epithelial cells (EGF, KGF) – faster re‐ epithelialization • Endothelial cells (VEGF, bFGF) ‐ vascularization • Fibroblasts (bFGF, PDGF) ‐ dermis regeneration • Host Stem Cells (SDF‐1, IGF‐1) ‐ epithelial, endothelial, neural, etc. • Inhibit scar formation • Secrete TGF beta 3 and other anti‐scar factors (HGF, VEGF) • Regulate MMPs/TIMPs

Q4 What is the history of the use of Amnion as a regenerative treatment?  1910 - thermal injury and ocular wound cover • (Davis) 550 cases • (Sabella similar findings)  1913 - Used Amnion to treat burns • (Sabella & Stern)  1940 - ophthalmology grafts (DeRoth)  1970ʼs - fell out of favor due to HIV  1995 - ophthalmic neurotrophic ulcers (Kim and Teng) • Significant improvement • Rapid healing

 2005 - Aseptic recovery, cryopreservation and sterile packaging for wounds, tissue & bone void filler  2007 – Resurgence in use of Amnion to treat diabetic wounds  2013 – Wide-spread adoption for human orthopedics

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Q5 How and why does this technology work? • Amnion as a regenerative treatment & bioscaffold  “Human tested, animal approved”  Tissue and the tornado  Tissue is just Bricks & Mortar

    

Anti-Microbial Anti-Inflammatory Anti-Adhesion Anti-Fibrotic Anti-Tumorigenic

Human Diabetic Wound

Q6 Is there science? • 3472 Total Treatments – 89.97% Efficacy • Committed Trials at 5 Universities – Results of first two • University of Chihuahua, Mexico

• Bone Growth Study – Result 3 months of bone growth in the 1st month

North Carolina State University • Wound Study in Horse

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Equine Animal

StemWrap – Clinical trial

Use of equine amniotic allograft as source of extracellular matrix to heal distal limb wounds in horses Barcelo-Fimbres M, Schnabel LV, Sorum M, Campos-Chillon LF, Culp A, Rivera R.

Objective: To evaluate wound contraction rates and closing using equine amniotic allografts (eAM). Materials and Methods: Fifteen clinical cases were evaluated for 60 days Control (n=4) treated by standard care (i.e. lavaging, debridement, and banding) eAM (n=11) StemWrap membrane and 2 mL StemWrap+ injection Variables: Wound area (WA) was analyzed using Image J software based on pixels/mm. Wound contraction rate (WCR): Initial WA (day 0) - WA at given day Initial WA x 100. Wound daily contraction (WDC):mm2/day of WA covered up to day 20 and 60.

StemWrap Clinical Trial

StemWrap – Clinical trial

Results: A) No allergic reactions or infections were observed using eAM. Infections

0/11

0/4

B) Higher Wound Daily Contraction was observed. WDC eAM

20 Days 2.4 mm2/day

60 Days 1.8mm2/day

Control

0.8 mm2/day

0.6mm2/day

Control eAM (StemWrap)

2.5 WDC (mm2/day)

Allergic reactions eAM Control

2 1.5 1 0.5 0 20

Days

P<0.001

StemWrap Clinical Trial 100.0

Wound Treatment Results:

90.0

WCR

20 Days

60 Days

eAM

47.3%

84.2%

Control

13.8%

41.3% P<0.05

80.0

y = -0.0299x2 + 3.402x - 0.3599 R² = 0.9316

70.0

WCR (%)

Faster Wound Closure Ratio (WCR) for StemWrap over the typical standard of care -At day 20 there was a 3.4x WCR increase -At day 60 a 2x WCR increase

60.0

Kristin Loncar, DVM, MS, DACT

50.0 40.0 30.0

10.0 0.0

Associate Veterinarian Equine Medical Services Columbia, MO y = 0.6856x + 0.1683 R² = 0.96

20.0

40 Days

StemWrap

Control

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Mechanism of Action Amnion is attracted to the inflammation. Through mRNA and Stromal Derived Factor 1, the presence of Amnion significantly upregulates circulating progenitor cells to the Amnion.

Murine Parabiosis Study Mice had their Bone Marrow MSC Died with Green Fluorescent Protein (GFP)

Mice were un‐died, wild‐type (WT) Mice

2015 Stanford Study

Murine Parabiosis Model

2 3

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Murine Parabiosis Model

2 3

Murine Parabiosis Model

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Q7 Advantages over other treatments? Concentration Agent Reaction

Site Produced

In Vitro Growth

Cell Banking

Mechanical Stimulation

Manipulation

Collection

PRP, IRAP

Stormal Vascular Fraction

Adipose, Bone Marrow, Dental Pulp

Umbilical Cord Blood

Shockwave, Low Light Laser, Cold Laser

Chiropractic, Acupuncture

Amnion

*

 

        

Off-the-shelf Product Doesn't Require Multiple Treatments

 

Doesn't Require Painful Harvesting Treat same day as diagnosis Cures tissue damage



  



 

Doesn't Require Expensive Equipment Doesn't Require Surgical Space/Lab



 



Doesn't Require Extensive Training Can be used in the Field

* Multiple treatments may be required based on the severity of the injury and the age/health of the



donor or animal being treated.

Q8 What can it be used on?

Products AniMotion

Type/(Content) Liquid Allograft (1mL) (Stem cells + ECM + GF)

Applications

Use Chronic orthopedic, muscle, ligament and tendon repair. Alternative to BM/Fat stem cells.

Internal Wounds

AniMatrX

Liquid Allograft (1mL) (ECM + GF)

Internal Wounds

Severe orthopedic, joints, ligament and tendon repair. Alternative to PRP and IRAP.

AniMatrX D

Lyophilized acellular implantable allograft (Sold in packs of 5)

Internal Wounds

Implantable treatment of high motion joints, less severe tendon & ligament problems

StemWrap

Treated Amnion

External Wounds

Accelerates healing and lessens the scarring of surface wounds.

StemWrap+

Liquid Allograft (2mL) (ECM + GF)

External Wounds

Accelerates healing and lessens the scarring of surface wounds. Accelerates healing and lessens the scarring of surface wounds.

StemWrap D

Lyophilized acellular implantable bioscaffold (Sold in packs of 5)

External Wounds

AniOcular

Treated Amnion Disc

Eye Wounds

Eye abrasions and ulcers (Ocular surface reconstruction)

AniOcular+ (Drops)

Liquid Allograft (2mL) (ECM + GF)

Eye Wounds

Eye abrasions and ulcers (Ocular surface reconstruction)

AniOcular D

Lyophilized acellular liquid eye drops (Sold in packs of 5)

Eye Wounds

Eye abrasions and ulcers (Ocular surface reconstruction)

BioScaff

Treated Amnion

Surgical

Sterile Surgical Bioscaffold Strips designed for incision

Q9 How long does it take to work and risks? Efficacy Efficacy at 89% on proven indications. 3472 Total Treatments – 89.97% Efficacy Product may travel to treat more pervasive inflammation.

Safety No Documented Severe Adverse Events Reported since 1910. Minor swelling or pain reported in less than 2.7% of cases; resolved in under 72 hours. No impact on efficacy.

Weekly Joint Healing Profile 120% 100% 80% 60% 40% 20% 0%

1 25% ‐ Immediate

3 40% ‐ Graduate

4 25% ‐ Slow Hocky Stick

6 10% ‐ No Response

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Q10 The Business of Amnion – Take-Aways The most expensive resource in veterinary medicine is time.  All Natural – Not Treating Symptoms  Treating same day as diagnosis  Faster healing with more structural integrity of tissue.  Veterinarian has more time cause you are treating once  Total cost of wound treatment is less  Not referring your best clients  Margin is made on the product  Works with Mechanical Stimulation such as Laser or Shockwave

Thank you

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Wellness and Soft Skills

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Wellness and Soft Skills

Tamara Hancock, DVM, MS, PhD

Clinical Pathologist, Assistant Professor, Coordinator of Curriculum and Student Outcomes University of Missouri - College of Veterinary Medicine Columbia, Missouri

Kerry Karaffa, PhD

Psychologist and Mental Health Coordinator University of Missouri - College of Veterinary Medicine Columbia, Missouri

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Mental Health Experiences and Service Use Among Veterinary Professionals

Mental Health in the Veterinary Profession

Kerry Karaffa, Ph.D., Licensed Psychologist

 Research suggests veterinary students and professionals may experience high rates of:  Depression and anxiety 1,2,3  Alcohol abuse1,4  Suicidality5,6,7

Tamara Hancock, DVM, MS, Dipl. ACVP (clinical), Ph.D. University of Missouri College of Veterinary Medicine

Mental Health in the Veterinary Profession

Nett et al. (2015)7

Merck Animal Health Veterinary Well-being Study8

 11,627 U.S. veterinarians

 3,540 U.S. veterinarians

 9% reported current serious psychological distress.

 5% reported current serious psychological distress.

 31% reported depressive episodes since veterinary school.

 Lower well-being than the general public.

 Combination of personality characteristics and environmental stressors8  Long hours and heavy workload9

Contributing Factors

 Professional isolation10  Organizational stressors11  Work-family conflict12  Compassion fatigue13  Reluctance to seek help7

 Three components of self-compassion:55  Positive mental health is necessary to maintain high standards of care.14,15

Mental Health Impacts on Professional Practice

 Stress, burnout, and depression are associated with:  Impaired judgement and medical errors16,17,18  Decreased empathy19,20  Reduced job satisfaction and intention to leave21,22,23

 Treating workplace mental health issues provides positive cost offsets for employers.24  Employees who received mental health treatment are similarly productive to employees without a history of mental health concerns.25

SelfCompassion

1. Self-kindness: Offering kindness toward oneself in difficult situations rather than judgement. 2. Common humanity: Seeing one’s personal experiences as a part of being human rather than isolations. 3. Mindfulness: Being able to maintain a balanced perspective on one’s painful thoughts and feelings.

 Negatively associated with depression and anxiety,31,56,57 maladaptive perfectionism,31,58 and compassion fatigue.59  Positively associated with well-being variables, such as self-esteem,31 motivation for self-improvement,60 and life satisfaction.31

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 Depression - Patient Health Questionnaire (PHQ-9)26  Anxiety - Generalized Anxiety Disorder 7-item (GAD-7)27  Alcohol Use - Alcohol Use Disorders Identification TestConsumption scale (AUDIT-C)28

 Identify the prevalence of mental health concerns among veterinary professionals.

Purpose of the Study

 Examine differences in mental health concerns based on gender and professional experience.  Explore the relationships between mental health concerns and self-compassion.

 Lifetime and 12-month prevalence of serious suicidal thoughts  12-month prevalence of opioid use for non-medical reasons

Measures

 Adapted from the NIDA-modified ASSIST screening tool28  These data are scarce4 and this may be the first study to evaluate it in a United States sample of veterinary professionals.

 Lifetime and 12-month prevalence of non-suicidal self-injury (NSSI)  NSSI has not been assessed in a sample of post-graduate veterinary professionals.

 Identify rates of mental health service use.

 Self-Compassion Scale-Short Form (SCS-SF)30  Self-compassion has been positively associated with well-being variables31

 History of using professional mental health services

 31 geographically-diverse states.  ~70% were female.

 Population of veterinary professionals belonging to state VMAs in the United States.

Population and Sampling Methods

 Partnered with 17 (33.3%) of 51 state VMAs for recruitment.  State VMAs emailed recruitment materials or recruited through approved electronic media outlets.

 Most identified as White (94%), heterosexual (92%), and married (71%).

Participants (n = 475)

 The average age was 47 (SD = 14).  Average of 21 (SD = 14) years of professional experience.  Most were licensed veterinarians (90%) and predominantly small animal practitioners (72%).

 Participation involved completing a confidential online Qualtrics32 survey.

 ~70% reported practicing in a suburban or urban location.

 19% reported current clinical levels of depression.  Only 8% of U.S. adults scored similarly on the same measure.34

 Depending on the research question, we conducted:

Data Analyses

    

Descriptive statistics Chi-square tests One sample t-tests Product-moment correlations Point-biserial correlations

 For non-normality, we used a non-parametric bootstrapping33 procedure with 5,000 resamples.  We used an alpha level of .05 for all analyses.

Results: Prevalence of Depression and NSSI

 11% reported engaging in NSSI at some point.  This prevalence rate is higher than rates in community samples (4% to 6%).35,36,37  Karaffa and Hancock38 found almost 25% of veterinary students reported engaging in NSSI at some point.

 Slightly more than 1% reported engaging in NSSI in the last 12 months.  This prevalence rate is consistent with rates reported in U.S. adults34

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 22% reported current clinical levels of anxiety.

 27% reported seriously thinking about killing themselves at some point.

Results: Prevalence of Suicide

 This rate is about twice as high as in community samples (14% to 16%).39,40

 About 10% reported seriously thinking about killing themselves in the last 12 months.  Past-year suicidal ideation was also twice as high as in community samples (4%).41

Results: Prevalence of Anxiety and Substance Use

 6% reported attempting suicide at some point.  Community samples report rates of 4% to 6%.39,40

Results: Gender Differences in Depression, Anxiety, and Substance Use

Results: Professional Experience and Mental Health

 Gender differences in alcohol use or opioid use for non-medical reasons were non-significant.  These findings are consistent with results among a sample of veterinary medical students38  They are inconsistent with other studies which have shown that men tend to drink more heavily than women,1,48 and women tend to report higher rates of opioid abuse.49

 Years of professional experience negatively correlated with:  Anxiety scores for both men (r = -.40) and women (r = .18).  Depression among men (r = -.39), but this relationship was non-significant among women.  Past-year NSSI for women (rpb = -.12), but not for men.

 The relationships between years of experience and other variables were non-significant for both men and women.

 This is similar to the 15% figure reported using the same measure in a community sample.43

 3% reported using prescription opioids for nonmedical reasons in the last 12 months.  The past-year prevalence rate in U.S. general population is similar, between 4% to 5%. 41,44

 Women were more likely report ever engaging in NSSI (φ = .19), but differences in past-year NSSI were nonsignificant.

 Women reported higher levels of depression (d = 0.73) and anxiety (d = 0.43).  This is consistent with research in both community34,42 and veterinary samples.34,38

 This is consistent with rates reported among primary care (20%)27 and community (19%)42 samples.

 16% of participants scored above the cut score for detecting alcohol abuse.

Results: Gender Differences in Suicide and NSSI

 Gender differences in NSSI are inconclusive and may depend on how the behavior is operationalized.45,46

 Women were more likely to have ever seriously think about killing themselves (φ = .13), but differences in pastyear ideations were non-significant.  Nett et al.7 found that women reported higher rates of suicidal ideation, but other researchers have found nonsignificant gender differences.1

 Women were more likely to report attempting suicide at some point (φ = .10).  This is consistent with some previous studies.47  Other studies have found similar rates of suicide attempts among men and women in the veterinary profession.7,38

Results: Professional Experience and Mental Health

 Although associations between experience and mental health were more robust among men, women still reported higher levels of distress across their careers.  Other research suggests younger veterinarians with less practice experience tend to experience higher levels of psychological distress7,50,51  May be due to differences in perceived stressors,51 including loan debt and professional competition, or cohort effects.7

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Results: Comparisons to Veterinary Students

 Compared to a sample of 573 veterinary medical students,38 veterinary professionals in the current sample reported lower scores on:  Depression (d = 0.92)  Anxiety (d = 0.86)  Alcohol use (d = 0.62)

 These findings are consistent with studies showing young adults tend to experience higher rates of mental health concerns than middle-aged and older adults.42

Results: Comparisons to Veterinary Students

 This may point to differences in perceived stress between veterinary students and professionals regarding concerns about maintaining high academic performance52 and difficulties managing workload.15,53,54  These findings highlight the importance of:  Supporting student wellness initiatives  Providing access to mental health services  Preparing students to transition effectively to postgraduate employment positions

 62% have used some form of professional mental health service in the past.

Results: SelfCompassion and Mental Health

 Self-compassion scores were negatively associated with: Depression (r = -.59) Anxiety (r = -.62) NSSI in the last 12 months (rpb = -.14) Serious suicidal ideation in the last 12 months (rpb = .30)  Having a history of attempting suicide (rpb = -.24)    

 Individual counseling and medication were most common.

Results: Mental Health Service Use

 22% received services in the last year.  12% were currently receiving some form of mental health care.

Clinical levels of depression

At some point

Within the last year

Currently

76%

32%

21%

Clinical levels of anxiety

78%

34%

16%

Current alcohol abuse

68%

28%

13%

Nett et al. 7 found that among veterinarians who reported serious psychological distress, 59% were not currently receiving mental health care.

 Mental health among veterinary professionals is complicated.

Results: Mental Health Service Use

 Veterinary professionals in distress may seek mental health services less frequently than other populations.  Approximately 65% of U.S. adults who experienced a major depressive episode in the last year reported seeking mental health services in the last year,41 compared to 32% in this sample.

Discussion: Mental Health in the Veterinary Profession

 Based on this study, veterinary professionals seem to experiences higher rates of depression and suicidality, but similar rates of other concerns, compared to the general public.

 Inconsistent findings may be the result of sampling procedures and measurement choices.  Using multiple measures gives a broader perspective on the issue.

 Measures of pathology do not necessarily elucidate other facets of well-being.

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Discussion: Gender Differences

 Gender differences may be a product of economic and socio-political factors7, professional stressors, and differential experiences regarding family stress and support.62,63  Women may have qualitatively different experiences in the profession.  Research suggests women may demonstrate greater emotional openness than men64,65 and may be more likely to candidly report psychological distress.

Discussion: Early Career Professionals

 Self-compassion may be an important protective factor for well-being.

Discussion: Selfcompassion

 Self-compassion is associated with decreased maladaptive perfectionism,31 which is often a concern among veterinary professionals.67

 Self-compassion may be a fruitful target for interventions.  Brief or online interventions have been shown to improve self-compassion.68,69,70  Interventions often include developing skills in mindfulness, perspective-taking, and self-reflection and can be supported within organizations.

 Veterinary professionals providing clinical and nonclinical services in both suburban/urban and rural areas are represented in the dataset.  This is the first study to assess NSSI, opioid use for non-medical reasons, self-compassion, and their correlates in a sample of post-graduate veterinary professionals.

 Veterinarians’ views about career satisfaction may be related to the support they receive in their first job after graduation.65

 Low rates of service use among clinical groups underscores the importance of understanding barriers to seeking services, including:

Discussion: Service Use

 Use of several psychometrically-sound, validated measures of mental health.

Strengths

 Students and early career professionals may be at particular risk for mental health problems, which highlights the need for mentorship at these times.

Limitations

     

Stigma71 Mental health literacy72 Knowledge about services that are available15,73 Anticipated utility73 Concerns about confidentiality15,74,75 Financial considerations76

 The non-probability sampling methods limit the generalizability of the findings.  The dataset did not include veterinary professionals from every state, nor did it include professionals who were not members of their respective state VMAs.  Self-reported data may be susceptible to recall bias.  We did not measure other facets of psychological wellbeing. 76      

Self-acceptance Autonomy Environmental mastery Positive relationships Purpose in life Personal growth

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Questions

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Cardwell, J. M., Lewis, E. G., Smith, K. C., Holt, E. R., Baillie, S., Allister, R., & Adams, V. J. (2013). A cross-sectional study of mental health in UK veterinary undergraduates. The Veterinary Record, 173(11), 266-266.

Hafen, M., Reisbig, A. M., White, M. B., & Rush, B. R. (2008). The first-year veterinary student and mental health: the role of common stressors. Journal of Veterinary Medical Education, 35(1), 102-109.

Harling, M., Strehmel, P., Schablon, A., & Nienhaus, A. (2009). Psychosocial stress, demoralization and the consumption of tobacco, alcohol and medical drugs by veterinarians. Journal of Occupational Medicine and Toxicology, 4(4).

Jones-Fairnie H., Ferroni P., Silburn S., & Lawrence, D. (2008). Suicide in Australian veterinarians. Australian Veterinary Journal, 86(4), 114-116.

Mellanby, R. J. (2005). Incidence of suicide in the veterinary profession in England and Wales. The Veterinary Record, 157(14), 415.

Nett, R. J., Witte, T. K., Holzbauer, S. M., Elchos, B. L., Campagnolo, E. R., Musgrave, K. J., ...& Pride, K. R. (2015). Risk factors for suicide, attitudes toward mental illness, and practice-related stressors among US veterinarians. Journal of the American Veterinary Medical Association, 247(8), 945-955.

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Gardner, D. H., & Parkinson, T. J. (2011). Optimism, self-esteem, and social support as mediators of the relationships among workload, stress, and well-being in veterinary students. Journal of Veterinary Medical Education, 38(1), 60-66.

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64. Komiya, N., Good, G. E., & Sherrod, N. B. (2000). Emotional openness as a predictor of college students' attitudes toward seeking psychological help. Journal of Counseling Psychology, 47(1), 138. 65. Mackenzie, C. S., Gekoski, W. L., & Knox, V. J. (2006). Age, gender, and the underutilization of mental health services: The influence of helpseeking attitudes. Aging and Mental Health, 10(6), 574-582. 66. Heath, T. J. (2002). Longitudinal study of veterinarians from entry to the veterinary course to 10 years after graduation: Attitudes to work, career and profession. Australian Veterinary Journal, 80(8), 474-478. 67. Gaspar, M. (2017). Why perfectionism is not perfect. Veterinary Team Brief, 50-53. 68. Krieger, T., Martig, D. S., van den Brink, E., & Berger, T. (2016). Working on self-compassion online: A proof of concept and feasibility study. Internet Interventions, 6, 64-70. 69. Neff, K. D., & Germer, C. K. (2013). A pilot study and randomized controlled trial of the mindful self‐compassion program. Journal of Clinical Psychology, 69(1), 28-44. 70. Smeets, E., Neff, K., Alberts, H., & Peters, M. (2014). Meeting suffering with kindness: Effects of a brief self‐compassion intervention for female college students. Journal of Clinical Psychology, 70(9), 794-807. 71. Corrigan, P. W. (2004). How stigma interferes with mental health care. American Psychologist, 59(7), 614-625. 72. Coles, M. E., & Coleman, S. L. (2010). Barriers to treatment seeking for anxiety disorders: Initial data on the role of mental health literacy. Depression and Anxiety, 27(1), 63-71. 73. Eisenberg, D., Golberstein, E., & Gollust, S. E. (2007). Help-seeking and access to mental health care in a university student population. Medical Care, 45(7), 594-601. 74. Givens, J. L., & Tjia, J. (2002). Depressed medical students' use of mental health services and barriers to use. Academic Medicine, 77(9), 918-921. 75. Kogan, L. R., Schoenfeld-Tacher, R., & Hathcock, J. (2012). Psychological Services for US and International Veterinary Students. Journal of Veterinary Medical Education, 39(1), 83-92. 76. Mojtabai, R. (2005). Trends in contacts with mental health professionals and cost barriers to mental health care among adults with significant psychological distress in the United States: 1997–2002. American Journal of Public Health, 95(11), 2009-2014. 77. Ryff, C. D. (1989). Happiness is everything, or is it? Explorations on the meaning of psychological well-being. Journal of Personality and Social Psychology, 57(6), 1069.

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Wellness and Soft Skills

Shelia Taylor, DVM

Instructor, Ozarks Technical Community College - Bioclinical Sciences Department Springfield, Missouri

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What is Mental Health and Mental Illness?

Mental Health First Aid & A First Hand Journey through Depression, Anxiety and Suicide

Mental

Health encompasses our emotional, psychological and social well-being. It

affects how we think, feel, and act.

Shelia Taylor, D.V.M. MVMA 2019 convention

What is Mental Health and Mental Illness? Mental

Illness is a health condition that involves changes in emotion, thinking, or behavior (or a combination of these). Is

often associated with distress and/or problems functioning in work, social or family settings.

What is Mental Health and Mental Illness?  Mental

illness is extremely common. In a given year:

 Nearly

one in five (19 %) of adults in the US experience some form of mental illness

 One

in 24 (4.1 percent) has a serious mental illness (this would include a major depressive disorder, schizophrenia and bipolar disorder)

 One

in 12 (8.5 percent) has a diagnosable substance abuse disorder

 Mental

illness is treatable. The vast majority of individuals with mental illness continue to function in their daily lives.

 Mental

illness is nothing to be ashamed of. It is a medical problem, just like heart disease, cancer or diabetes.

What is Mental Health First Aid? The

Mental Health First Aid Action Plan (ALGEE) Assess Listen Give

for risk of suicide or harm nonjudgmentally

Reassurance and Information appropriate professional

Encourage

help

Encourage

self-help and other support strategies

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What is Mental Health First Aid?

Mental

Health First Aid is a training program that teaches members of the public how to help a person:  That

is developing a mental health problem

 That

is experiencing a worsening of an existing mental health problem

 That

is experiencing a mental health crisis

Missouri Department of Mental Health

Mental Health First Aid (mentalhealthfirstaid.org)

Is It Depression or Is It Just Sadness? Sadness

is a normal human emotion

 Everyone

experiences sadness at times

 Usually

triggered by a difficult, hurtful, challenging or disappointing event

 We

tend to feel sad about something

 When

the situation resolves or our emotional feeling fades the sadness goes away

Is It Depression or Is It Just Sadness? Depression

is an abnormal emotional state

 Depression

is a mental health illness that affects an individual’s thinking, emotions, perceptions and behaviors in extensive and chronic ways  Depression saps energy, motivation and ability to experience other emotions such as joy, excitement, satisfaction, connection and meaning  It makes most people impatient, quicker to become angry or frustrated, quicker to break down, and tends to take much longer to bounce back from everything

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The True Symptoms of Depression  To

be diagnosed with depression, one needs to have a least 5 of the following symptoms for a minimum of at least 2 weeks: (the severity must also be considered so please use these as a guideline only) A

depressed or irritable mood the majority of the time

A

loss or decrease of pleasure or interest in most activities, even those one likes

 Significant

is characterized by a sense of doubt and vulnerability about future events  Anxiety  Anxious

and Depression often are seen together individuals focus on their future prospects, and fear that those will be bad

changes in weight and / or appetite

 Disturbances A

Depression and Anxiety  Anxiety

in falling asleep, staying asleep, or sleeping excessively

feeling of being slowed down in one’s movement or feeling restless most days

 Feeling

tired, sluggish, or having low energy most days

 Having

feelings of excessive guilt or worthlessness most days

 Having

problems with thinking, focus, creativity, concentration, and decision making most days

 Having

thoughts of self-harm, dying or suicide

Signs of Anxiety No list is all inclusive, but here are the common anxiety symptoms as they are often described.  Variations

in heart activity: faster, slower, skipping, louder  Feeling light headed and/or dizzy  Labored and impaired breathing  Pain and/or heaviness in the chest  Numbness and/or tingling in the toes, fingers, and scalp  Sweating  Blushing  Feeling weak  Urge to run

 Bodily

trembling cracking or trembling pains: back pain, headache  Stomach upset  Urge to urinate or have a bowel movement  Feeling "hyper"  Feelings of head expansion or contraction  Visual disturbances  Feelings of unreality as if you're no longer inside your body  Voice

 Various

How to Live with Depression First,

know that you are not alone. Many people live with depression and anxiety.

How to Live with Depression  Recovering

from depression requires action, but taking action when you’re depressed is hard. In fact, just thinking about the things you should do to feel better, like going for a walk or spending time with friends, can be exhausting.

 The

key to depression recovery is to start with a few small goals and slowly build from there. Draw upon whatever resources you have. You may not have much energy, but you probably have enough to take a short walk around the block or pick up the phone to call a loved one.

 Take

things one day at a time and reward yourself for each accomplishment. The steps may seem small, but they’ll quickly add up. And for all the energy you put into your depression recovery, you’ll get back much more in return.

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How to Live with Depression Depression self-help tip 1: Cultivate supportive relationships Depression self-help tip 2: Get moving Depression self-help tip 3: Challenge negative thinking Depression self-help tip 4: Do things that make you feel good Depression self-help tip 5: Eat a healthy, mood-boosting diet When should one get professional help? If you find your depression getting worse and worse, seek professional help. Needing additional help doesn’t mean you’re weak. Sometimes the negative thinking in depression can make you feel like you’re a lost cause, but depression can be treated by a number of different methods and you can feel better! Don’t forget about these self-help tips, though. Even if you’re receiving professional help, these tips can be part of your treatment plan, speeding your recovery and preventing depression from returning.

Some Words about Suicide

Suicide statistics

Things You Can Do If You Think Someone May Be Suicidal:  Ask

the person directly if they are thinking about hurting themselves.

 Take

the person seriously.

 Listen

without judging.

 Offer

to go with the person to a Counseling Center.

 Tell

328

someone. Get help.

 Provide

the National Suicide Prevention Hotline number 1800-273-TALK (800-273-8255)

 If

a person is having active suicidal thoughts – Do NOT leave them alone.

 Dial

911.

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And here is just one of the reasons that I stay

?? Questions, Comments, Shared Stories ??

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Wellness and Soft Skills

Brian Patrick, DVM

Senior Technical Services Veterinarian - Bayer Animal Health Columbia, Illinois

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12/13/2018

Today’s Objectives  Identify specific communication tools to increase confidence in client interactions  Commit to using 2 tools in practice

Building Trust with Clients

Why does communication matter?

Our Plan…  Essential communication tools • • • • •

Power of Nonverbal Questioning skills: History taking / building trust Active Listening Empathy Ask‐Tell‐Ask

 Translation to practice

Reason 1 Reason 2

Five reasons communication is key in veterinary practice

Reason 1

 History taking

Diagnostic Accuracy

 Up to 85% of data necessary to accurately obtain a diagnosis comes from the history  History alone has significantly higher correlation to accurate diagnosis than any other diagnostic modality alone (PE, basic tests, imaging)

Reason 3

 Missed diagnoses are most often (56%) the result of breakdowns related to history taking

Reason 4 Reason 5

(Paley et al 2011, Schattner 2012, Kaplan et al., 1995, Marvel et al., 1999; Peterson et al., 1992; Rabinowitz et al., 2004, Stewart et al., 1986; Jagosh et al 2011; Singh et al 2013)

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Barriers How long does it take a doctor to interrupt a patient?

Diagnostic Accuracy

Improved Adherence

Reason 2

Adherence in vet med

 Range between 23‐65%  Problems cited:

 18 seconds (Beckman & Frankel 1984)  23 seconds (Marvel et al 1999)  12 seconds (Rhoads et al 2001)

• information Communication • Trust not established • Lack of follow‐up • Client opinion not considered

Only 1 of 52 interrupted patients returned to or completed their concerns

Patients have an average of 3 concerns per office visit

(AAHA 2009; AAHA 2003; Adams, V 2002)

Quality of Patient Care

Formal Complaints Liability Reason 4

Reason 3 • Ineffective team communication is the root cause of 66% of reported medical errors • Patient care suffers

Up to 82% of formal complaints and malpractice cases are because Communication

    

Clients felt misinformed Informed consent not obtained Client reported feeling disrespected Felt like opinion did not matter Procedure not explained

Communication

JCAHO Root Causes & Percentages for Sentinel Events ‐ All Categories (Jan 1995−Dec 2005); TeamSTEPPS, Agency for Healthcare Research and Quality and Dept of Defense, 2008

Satisfaction Client/Team Reason 5

Client’s perception = Your reality

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Domains of Communication Content

Communication

• “What” we say

Nonverbal

• “How” we say it

Perception

• Our internal thoughts and feelings

12/13/2018

Practice Management

Building Client Trust What’s your welcoming ritual? • 78% patients want their doctors to shake hands • 93% want to be greeted by name • 96% want Dr. to intro by name

Building Trust: Essential Tools Nonverbal awareness Open-ended Questions /Funneling

AskTell-Ask

Active Listening/ Empathy

(Makoul, 2007)

Why non-verbal awareness?

 Up to 80% of communication is nonverbal  Awareness takes no extra time

What is nonverbal communication? Definition All of our behavior signals exclusive of verbal content

Categories: Proxemics

Categories: Kinesics

 Gestures  Touch  Posture

 Proxemics  Autonomic changes

nonverbal message is more accurate of feelings and will predict behavior

 Body tension

 Kinesics  Paralanguage

 With mixed messages,

 Facial expressions