The Modern Equine Vet May 2015 by The Modern Equine Vet

The Modern

Equine Vet www.modernequinevet.com

Vol 5 Issue 5 2015

Protecting those pearly whites

Nothing to sneeze at EIA, EHV, wound healing and more

Table of Contents

Cover story:

6 Protecting the horse's pearly whites Cover ©shutterstock/Studio 37

infectious diseases

Nothing to sneeze at.............................................................................................................10 Dermatology

Encapsulated stem cells accelerate wound healing..................................................12 Technician Update

Medical records in the equine practice—how to reduce risk......................15 News

EIA reported in West Tennessee...........................................................................4 Oregon reports EHV................................................................................................4 Sarcoids remain most common equine tumor........................................17 Horse tendon's ability to recover......................................................................17

advertisers Merck Animal Health.................................................. 3 Luitpold Animal Health.............................................. 5

Aurora Pharmaceuticals............................................. 7 AAEVT............................................................................14

The Modern

Equine Vet Sales: Robin Geller • newbucks99@yahoo.com Editor: Marie Rosenthal • mrosenthal@percybo.com Art Director: Jennifer Barlow • jbarlow@percybo.com contributing writerS: Paul Basillo • Kathleen Ogle COPY EDITOR: Patty Wall Published by PO Box 935 • Morrisville, PA 19067 Marie Rosenthal and Jennifer Barlow, Publishers percybo media  publishing

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Talk to your Merck Animal Health representative about proper use and safe handling of Regu-Mate. Avoid skin contact. Always wear protective gloves when administering Regu-Mate. This product is contraindicated for use in mares with a previous or current history of uterine inflammation. Pregnant women, or women who suspect they are pregnant, should not handle this product. See related page in this issue for details.

News notes

Regu-Mate® (altrenogest) Solution 0.22% (2.2 mg/mL) CAUTION: Federal law restricts this drug to use by or on the order of a licensed veterinarian. DESCRIPTION: Regu-Mate® (altrenogest) Solution 0.22% contains the active synthetic progestin, altrenogest. The chemical name is 17α-allyl-17ß-hydroxyestra-4,9,11-trien-3-one. The CAS Registry Number is 850-52-2. The chemical structure is: Each mL of Regu-Mate® (altrenogest) Solution 0.22% contains 2.2 mg of altrenogest in an oil solution.

INDICATIONS: Regu-Mate® (altrenogest) Solution 0.22% is indicated to suppress estrus in mares. Suppression of estrus allows for a predictable occurrence of estrus following drug withdrawal. This facilitates the attainment of regular cyclicity during the transition from winter anestrus to the physiological breeding season. Suppression of estrus will also facilitate management of prolonged estrus conditions. Suppression of estrus may be used to facilitate scheduled breeding during the physiological breeding season. CONTRAINDICATIONS: Regu-Mate® (altrenogest) Solution 0.22% is contraindicated for use in mares having a previous or current history of uterine inflammation (i.e., acute, subacute, or chronic endometritis). Natural or synthetic gestagen therapy may exacerbate existing low-grade or “smoldering” uterine inflammation into a fulminating uterine infection in some instances. PRECAUTIONS: Various synthetic progestins, including altrenogest, when administered to rats during the embryogenic stage of pregnancy at doses manyfold greater than the recommended equine dose caused fetal anomalies, specifically masculinization of the female genitalia. DOSAGE AND ADMINISTRATION: While wearing protective gloves, remove shipping cap and seal; replace with enclosed plastic dispensing cap. Remove cover from bottle dispensing tip and connect luer lock syringe (without needle). Draw out appropriate volume of Regu-Mate solution. (Note: Do not remove syringe while bottle is inverted as spillage may result.) Detach syringe and administer solution orally at the rate of 1 mL per 110 pounds body weight (0.044 mg/kg) once daily for 15 consecutive days. Administer solution directly on the base of the mare’s tongue or on the mare’s usual grain ration. Replace cover on bottle dispensing tip to prevent leakage. Excessive use of a syringe may cause the syringe to stick; therefore, replace syringe as necessary. WHICH MARES WILL RESPOND TO REGU-MATE® (altrenogest) SOLUTION 0.22%: Extensive clinical trials have demonstrated that estrus will be suppressed in approximately 95% of the mares within three days; however, the post-treatment response depended on the level of ovarian activity when treatment was initiated. Estrus in mares exhibiting regular estrus cycles during the breeding season will be suppressed during treatment; these mares return to estrus four to five days following treatment and continue to cycle normally. Mares in winter anestrus with small follicles continued in anestrus and failed to exhibit normal estrus following withdrawal. Response in mares in the transition phase between winter anestrus and the summer breeding season depended on the degree of follicular activity. Mares with inactive ovaries and small follicles failed to respond with normal cycles post-treatment, whereas a higher proportion of mares with ovarian follicles 20 mm or greater in diameter exhibited normal estrus cycles posttreatment. Regu-Mate® (altrenogest) Solution 0.22% was very effective for suppressing the prolonged estrus behavior frequently observed in mares during the transition period (February, March and April). In addition, a high proportion of these mares responded with regular estrus cycles post-treatment. SPECIFIC USES FOR REGU-MATE® (altrenogest) SOLUTION 0.22%: SUPPRESSION OF ESTRUS TO: 1. Facilitate attainment of regular cycles during the transition period from winter anestrus to the physiological breeding season. To facilitate attainment of regular cycles during the transition phase, mares should be examined to determine the degree of ovarian activity. Estrus in mares with inactive ovaries (no follicles greater than 20 mm in diameter) will be suppressed but these mares may not begin regular cycles following treatment. However, mares with active ovaries (follicles greater than 20 mm in diameter) frequently respond with regular post-treatment estrus cycles. 2. Facilitate management of the mare exhibiting prolonged DOSAGE CHART: estrus during the transition period. Estrus will be suppressed in mares exhibiting prolonged behavioral estrus either early Approximate Weight Dose or late during the transition period. Again, the posttreatment in Pounds in mL response depends on the level of ovarian activity. The 770 7 mares with greater ovarian activity initiate regular cycles 880 8 and conceive sooner than the inactive mares. Regu-Mate® 990 9 (altrenogest) Solution 0.22% may be administered early in 1100 10 the transition period to suppress estrus in mares with inactive 1210 11 ovaries to aid in the management of these mares or to mares 1320 12 later in the transition period with active ovaries to prepare and schedule the mare for breeding. 3. Permit scheduled breeding of mares during the physiological breeding season. To permit scheduled breeding, mares which are regularly cycling or which have active ovarian function should be given Regu-Mate® (altrenogest) Solution 0.22% daily for 15 consecutive days beginning 20 days before the date of the planned estrus. Ovulation will occur 5 to 7 days following the onset of estrus as expected for nontreated mares. Breeding should follow usual procedures for mares in estrus. Mares may be regulated and scheduled either individually or in groups. ADDITIONAL INFORMATION: A 3-year well controlled reproductive safety study was conducted in 27 pregnant mares, and compared with 24 untreated control mares. Treated mares received 2 mL Regu-Mate® (altrenogest) Solution 0.22% /110 lb body weight (2x dosage recommended for estrus suppression) from day 20 to day 325 of gestation. This study provided the following data: 1. In filly offspring (all ages) of treated mares, clitoral size was increased. 2. Filly offspring from treated mares had shorter interval from Feb. 1 to first ovulation than fillies from their untreated mare counterparts. 3. There were no significant differences in reproductive performance between treated and untreated animals (mares & their respective offspring) measuring the following parameters: • •

• • • • • • •

interval from Feb. 1 to first ovulation, in mares only. mean interovulatory interval from first to second cycle and second to third cycle, mares only. follicle size, mares only. at 50 days gestation, pregnancy rate in treated mares was 81.8% (9/11) and untreated mares was 100% (4/4). after 3 cycles, 11/12 treated mares were pregnant (91.7%) and 4/4 untreated mares were pregnant (100%). colt offspring of treated and control mares reached puberty at approximately the same age (82 & 84 weeks respectively). stallion offspring from treated and control mares showed no differences in seminal volume, spermatozoal concentration, spermatozoal motility, and total sperm per ejaculate. stallion offspring from treated and control mares showed no difference in sexual behavior. testicular characteristics (scrotal width, testis weight, parenchymal weight, epididymal weight and height, testicular height, width & length) were the same between stallion offspring of treated and control mares.

REFERENCES: Shoemaker, C.F., E.L. Squires, and R.K. Shideler. 1989.Safety of Altrenogest in Pregnant Mares and on Health and Development of Offspring. Eq. Vet. Sci. (9); No. 2: 69-72. Squires, E.L., R.K. Shideler, and A.O. McKinnon. 1989.Reproductive Performance of Offspring from Mares Administered Altrenogest During Gestation. Eq. Vet. Sci. (9); No. 2: 73-76. WARNING: Do not use in horses intended for food. HUMAN WARNINGS: Skin contact must be avoided as Regu-Mate® (altrenogest) Solution 0.22% is readily absorbed through unbroken skin. Protective gloves must be worn by all persons handling this product. Pregnant women or women who suspect they are pregnant should not handle Regu-Mate® (altrenogest) Solution 0.22%. Women of child bearing age should exercise extreme caution when handling this product. Accidental absorption could lead to a disruption of the menstrual cycle or prolongation of pregnancy. Direct contact with the skin should therefore be avoided. Accidental spillage on the skin should be washed off immediately with soap and water. INFORMATION FOR HANDLERS: WARNING: Regu-Mate® (altrenogest) Solution 0.22% is readily absorbed by the skin. Skin contact must be avoided; protective gloves must be worn when handling this product. Effects of Overexposure: There has been no human use of this specific product. The information contained in this section is extrapolated from data available on other products of the same pharmacological class that have been used in humans. Effects anticipated are due to the progestational activity of altrenogest. Acute effects after a single exposure are possible; however, continued daily exposure has the potential for more untoward effects such as disruption of the menstrual cycle, uterine or abdominal cramping, increased or decreased uterine bleeding, prolongation of pregnancy and headaches. The oil base may also cause complications if swallowed. In addition, the list of people who should not handle this product (see below) is based upon the known effects of progestins used in humans on a chronic basis. PEOPLE WHO SHOULD NOT HANDLE THIS PRODUCT. 1. 2. 3. 4. 5. 6. 7. 8.

Women who are or suspect they are pregnant. Anyone with thrombophlebitis or thromboembolic disorders or with a history of these events. Anyone with cerebral-vascular or coronary artery disease. Women with known or suspected carcinoma of the breast. People with known or suspected estrogen-dependent neoplasia. Women with undiagnosed vaginal bleeding. People with benign or malignant tumors which developed during the use of oral contraceptives or other estrogen-containing products. Anyone with liver dysfunction or disease.

ACCIDENTAL EXPOSURE: Altrenogest is readily absorbed from contact with the skin. In addition, this oil based product can penetrate porous gloves. Altrenogest should not penetrate intact rubber or impervious gloves; however, if there is leakage (i.e., pinhole, spillage, etc.), the contaminated area covered by such occlusive materials may have increased absorption. The following measures are recommended in case of accidental exposure. Skin Exposure: Wash immediately with soap and water. Eye Exposure: Immediately flush with plenty of water for 15 minutes. Get medical attention. If Swallowed: Do not induce vomiting. Regu-Mate® (altrenogest) Solution 0.22% contains an oil. Call a physician. Vomiting should be supervised by a physician because of possible pulmonary damage via aspiration of the oil base. If possible, bring the container and labeling to the physician. CAUTION: For oral use in horses only. Keep this and all medication out of the reach of children. Store at or below 25°C (77°F). NADA# 131-310, Approved by FDA. HOW SUPPLIED: Regu-Mate® (altrenogest) Solution 0.22% (2.2 mg/mL). Each mL contains 2.2 mg altrenogest in an oil solution. Available in 1000 mL plastic bottles. * US Patents 3,453,267; 3,478,067; 3,484,462 Manufactured by: DPT Laboratories, San Antonio, TX 78215 Distributed by: Intervet Inc., Millsboro, DE 19966

EIA reported in West Tennessee The Tennessee state veterinarian confirmed four cases of equine infectious anemia (EIA) in West Tennessee. Four horses stabled at three locations in Henderson T. stygius is a vector of equine infectious County recently tested positive for EIA. By May 14, no new anemia also known as swamp fever. EIA cases were reported. is transmitted through the fly’s bite, and “We take EIA very seriously,” said Charles Hatcher, symptoms include fever, anemia and DVM, the state veterinarian. “Early detection and contain- could result in death. An equine vaccine is available. ment are critical to preventing the spread [of this disease].” EIA is a viral disease most commonly transmitted by biting insects. At this time, there is no vaccine or treatment. Although an infected horse can run a low-grade fever or become lethargic, often there are no clinical signs. A horse remains infected throughout its lifetime and can pass the disease to other horses. Owners of EIA-positive horses have two options: lifetime quarantine of the animal or euthanasia. Tennessee state law requires any horse that is transported from its home farm to any event or other location have a negative Coggins test to screen for EIA antibodies. Veterinarians should advise owners to makes sure their horse’s Coggins test is current and that the animal does not have close contact with any horses that are not up-to-date. Cleanliness in and around the barn and a manure management plan can also help reduce the fly population. Tennessee normally experiences a few cases of EIA each year. For more information, contact the state veterinarian’s office at 615-837-5120. MeV

Shutterstock/irin-k

ACTIONS: Regu-Mate® (altrenogest) Solution 0.22% produces a progestational effect in mares.

Oregon reports equine herpes virus 1 Four Oregon horses showed neurological signs of equine herpes virus (EHV-1), according to the Oregon Department of Agriculture (ODA). In addition, another five horses exposed to EHV-1 developed fevers, but did not develop neurological signs. Eight farms are under quarantine, six in Marion County and two in Polk County, Oregon. By May 14, no new cases were reported, and two hospitalized patients responded to treatment and were sent home by their veterinarian. The exposed horses attended several recent events, including an Oregon High School Equestrian Team (OHSET) meet at the Linn County Fairgrounds on April 16–19, and rodeo events at Branton Arena, in Jefferson, Ore., April 19–20, as well as at the High Prarie Area in Eugene, Ore., from April 25–26. ODA continues to investigate the potential of any additional exposures. In addition, ODA has notified Oregon equine veterinarians and is working to notify horse owners. “All horses that attended the OHSET Willamette district meet on April 16–18 should refrain from any further shows or gatherings for the next 28 days and impose a self quarantine. Owners of stable 4

Issue 5/2015 | ModernEquineVet.com

mates of these OHSET horses should consult with their veterinarian to assess risk of exposure. High-risk horses should also refrain from shows or gatherings. The responsible thing for OHSET Willamette District attendees to do at this time is to stay home and monitor their horses. Call your veterinarian if you suspect any signs of illness,” recommended State Veterinarian Brad LeaMaster, DVM. The virus is widespread among the equine population. It is a common virus and may lie dormant for long periods and then reactivate during a period of stress, which can result in clinical disease. The most common way for EHV-1 to spread is by direct horse-to-horse contact. The virus can also be transmitted through contaminated equipment, clothing and hands. EHV-1 can cause respiratory disease, abortions in pregnant mares, neurologic disease, and in severe cases, death. Symptoms include fever, decreased coordination, nasal discharge, urine dribbling, loss of tail tone, hind limb weakness, leaning against a wall or fence to maintain balance, lethargy, and the inability to rise. While there is no cure, the symptoms of the disease may be treatable. MeV

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Available through your veterinarian There are no known contraindications to the use of intramuscular Adequan® i.m. brand Polysulfated Glycosaminoglycan in horses. Studies have not been conducted to establish safety in breeding horses. WARNING: Do not use in horses intended for human consumption. Not for use in humans. Keep this and all medications out of the reach of children. Caution: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Each 5 mL contains 500 mg Polysulfated Glycosaminoglycan. Brief Summary Indications: For the intramuscular treatment of non-infectious degenerative and/or traumatic joint dysfunction and associated lameness of the carpal and hock joints in horses. See Product Package Insert at www.adequan.com for Full Prescribing Information Adequan® is a registered trademark of Luitpold Pharmaceuticals, Inc. ©2015 Luitpold Pharmaceuticals, Inc., Animal Health Division Shirley, NY 11967. AHD110 Iss. 3/2015

cover story

Protecting

the horse’s pearly whites A systematic approach to equine dentistry

first started practicing equine dentistry, the oral examination focused mainly on whether the horse’s teeth needed to be floated. Malocclusions were identified and adjustments were made, and soft tissue was examined with an eye toward preventing trauma. Looking back, that narrow focus may have allowed other pathology to go overlooked and untreated, which can lead to progressive problems in the oral cavity.

B y 6

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“It is important to go through each patient systematically and place a check in the box for each issue that you find,” said Dr. Henry, owner of Midwest Equine Services in Elkhorn, Wis. “Examine each horse in the same manner and utilize your mirror and the other small, inexpensive instruments in your arsenal.” Dr. Henry boiled down his systematic approach into five components here at the 60th annual AAEP Convention in Salt Lake City. He

P a u l

examined dentistry practices for several other species, including humans, and incorporated the process as part of a thorough examination of the equine oral cavity.

1. Extraoral findings

Dr. Henry often looks for extraoral findings while the horse is sedated. If he finds some nasal discharge, he will ask the owner how long it has been occurring and whether it has smelled foul. A follow-up endoscopic examination

B a s i l i o

©shutterstock/gumbao

When Travis J. Henry, DVM,

a ed fd Ov r pp

(Sulfadiazine/trimethoprim) Oral Suspension

contains 400 mg combined active ingredient (333 mg sulfadiazine and 67 mg of trimethoprim)

“EQUISUL-SDT has been a welcome addition to my antimicrobial options. The spectrum of activity of sulfadiazine is very good, and the drug profile in the horse is favorable. Client feedback regarding EQUISUL-SDT has been overwhelmingly positive. Like me, they appreciate the convenient packaging, stability of the product over time, and the ease of application of a uniform oral suspension. Client compliance with prescribed treatment plans is improved. EQUISUL-SDT is therefore an excellent choice for use where susceptible organisms are present.” Dr. Peter Morresey Rood & Riddle Equine Hospital, Lexington, Kentucky

prOduct featureS • EQUISUL-SDT safety was demonstrated in a controlled study in horses at 1X, 3X and 5X the recommended dose for 30 days. • Apple flavored, easy-to-use liquid formulation. • Available to veterinarians in 280 mL, 560 mL and 900 mL bottles.

Evidence-based medicine with research to back it up. See prescribing information for EQUISUL-SDT in this issue. Aurora Pharmaceutical, LLC 1196 Highway 3 South Northfield, MN 55057 888-215-1256 • Fax 507-650-7250 www.aurorapharmaceutical.com info@aurorapharmaceutical.com

MaNufactured iN the uSa ad000016 05/2015

cover story

will be performed to see whether the discharge is related to the guttural pouch or sinusitis secondary to a potential tooth root abscess. “Bony swellings are common in dentistry,” he said. “We have to determine whether it is related to a left mandibular abscess or a 309 apical abscess or something else.” Epiphora, changes in musculature, discrepancy in temporomandibular joints, and enlargement of the lymph nodes are all extraoral findings that can affect the horse’s oral and overall health.

2. Occlusion

“Part of the occlusion examination has to be done with the speculum off, and part of it has to be performed with the speculum in

EQUISUL- SDT

(Sulfadiazine/Trimethoprim) Oral Suspension For use in horses only. NADA 141-360 CAUTION Federal law (USA) restricts this drug to use by or on the order of a licensed veterinarian. DESCRIPTION EQUISUL-SDT is a broad-spectrum antimicrobial from the potentiated sulfonamide class of chemotherapeutic agents. These two drugs block different sequential steps in the biosynthesis of nucleic acids. Sulfadiazine inhibits bacterial synthesis of dihydrofolic acid by competing with paraaminobenzoic acid. Trimethoprim blocks the production of tetrahydrofolic acid from dihydrofolic acid by reversibly inhibiting dihydrofolate reductase. The effect of the dual action is to reduce the minimum inhibitory concentration of each agent (synergism) and to convert a bacteriostatic action to a bactericidal action. Sulfadiazine is the non-proprietary name for 4-amino-N2-pyrimidinylbenzenesulfonamide. Trimethoprim is the non-proprietary name for 5-[(3,4,5¬trimethoxyphenyl)methyl]-2,4-pyrimidinediamine. Figure 1. Structure of sulfadiazine

Figure 2. Structure of trimethoprim

Part of the occlusion examination has to be done with the speculum off, and part with it in place. place,” Dr. Henry noted. The American Veterinary Dental College (AVDC) has identified two different types of malocclu-

known sensitivity to sulfonamides or trimethoprim should avoid exposure to this product. If an allergic reaction occurs (e.g., skin rash, hives, difficulty breathing, facial swelling) seek medical attention. PRECAUTIONS Prescribing antibacterial drugs in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to treated animals and may increase the risk of development of drug-resistant animal pathogens. The administration of antimicrobials, including sulfadiazine and trimethoprim, to horses under conditions of stress may be associated with acute diarrhea that can be fatal. If acute diarrhea or persistent changes in fecal consistency are observed, additional doses of EQUISUL-SDT should not be administered and appropriate therapy should be initiated. The safe use of EQUISUL-SDT has not been evaluated in breeding, pregnant, or lactating horses. Potentiated sulfonamides should only be used in pregnant or lactating mares when the benefits to the mare justify the risks to the fetus. Use of potentiated sulfonamides during pregnancy has been associated with an increased risk of congenital abnormalities that may be related to folate deficiency. In humans, sulfonamides pass through the placenta, are excreted in milk, and may cause hyperbilirubinemia-induced neurotoxicity in nursing neonates. Decreased hematopoetic activity and blood dyscrasias have been associated with the use of elevated doses and/or prolonged administration of potentiated sulfonamides. EQUISUL-SDT should be discontinued if prolonged clotting times, or decreased platelet, white blood cell or red blood cell counts are observed. Sulfonamides should be used with caution in horses with impaired hepatic function. Although rare, sulfonamide use has been associated with fulminant hepatic necrosis in humans. Neurologic abnormalities have been reported in several species following administration of potentiated sulfonamides. In horses, potentiated sulfonamides have been associated with gait alterations and behavior changes that resolved after discontinuation of the drug. The safe use of EQUISUL-SDT has not been evaluated in horses less than 1 year of age.

Each mL of EQUISUL-SDT contains 400 mg combined active ingredients (333 mg sulfadiazine and 67 mg trimethoprim) in an aqueous suspension. INDICATION EQUISUL-SDT is indicated for the treatment of lower respiratory tract infections in horses caused by susceptible strains of Streptococcus equi subsp. zooepidemicus. DOSAgE AND ADmINISTRATION Shake well before use. Administer EQUISUL-SDT orally at the dosage of 24 mg combined active ingredients per kilogram body weight (10.9 mg/lb) twice daily for 10 days. EQUISUL-SDT can be administered by volume at 2.7 mL per 45.4 kg (2.7 mL/100 lb) body weight. CONTRAINDICATIONS EQUISUL-SDT is contraindicated in horses with a known allergy to sulfadiazine, sulfonamide class antimicrobials, or trimethoprim. WARNINg Do not use in horses intended for human consumption. HUmAN WARNINgS Not for use in humans. For use in animals only. Keep this and all drugs out of the reach of children. Consult a physician in the case of accidental human exposure. Antimicrobial drugs, including sulfonamides, can cause mild to severe allergic reactions in some individuals. Avoid direct contact of the product with the skin, eyes, mouth, and clothing. Persons with a

ADvERSE REACTIONS Adverse reactions reported during a field study of 270 horses of various breeds, ranging from 1 to 25 years of age, which had been treated with either EQUISUL-SDT (n = 182) or with a saline control (n = 88) are summarized in Table 1. At least one episode of loose stool of varying severity was observed in 69 of 182 (38%) of the EQUISUL-SDT-treated horses, and 29 of 88 (33%) saline control horses. Of those animals experiencing loose stool, 2 of 182 (1.1%) of the EQUISUL-SDT-treated horses and 0 of 88 (0%) placebo-treated horses were removed from the study due to diarrhea (defined as at least one episode of watery stool). Both cases of diarrhea in this study were self-limiting and resolved without treatment within 5–10 days after discontinuation of EQUISUL-SDT. Table 1. Number of Horses with Adverse Reactions During the Field Study with EQUISUL-SDT Adverse Reactions Loose stool (including diarrhea)

Equisul-SDT (n=182)

Saline control (n=88)

69 (38%)

29 (33%)

Colic

3 (1.6%)

2 (2.2%)

Diarrhea

2 (1.1%)

0 (0%)

To report suspected adverse events, for technical assistance or to obtain a copy of the mSDS, contact Aurora Pharmaceutical LLC at 888-215-1256 or www.aurorapharmaceutical.com. For additional information about adverse drug experience reporting for animal drugs, contact FDA at 1-888-FDA-vETS or online at http://www.fda.gov/ Animalveterinary/SafetyHealth. CLINICAL PHARmACOLOgy Following oral administration, EQUISUL-SDT is rapidly absorbed and widely distributed throughout body tissues. Sulfadiazine levels are usually highest in the kidney, while the tissue concentration in other tissues is only slightly lower than plasma concentrations. Concentrations of trimethoprim are usually higher in the lungs, kidney, and liver than in the blood. Sulfadiazine

Issue 5/2015 | ModernEquineVet.com

sions. A skeletal malocclusion is an anatomic discrepancy in the relationship between the mandible and maxilla, and a dental malocclusion is a discrepancy between the position of an individual tooth within an otherwise normal jaw. Dr. Henry said that understanding which malocclusion is present in the horse can bring a better understanding of how to address the issue. A skeletal malocclusion cannot be corrected, but serial occlusal adjustments can be made for maintenance. On the other hand, a dental malocclusion may lead the clinician down the path to finding additional pathology that may need to be addressed in addition to the malocclusion itself.

and trimethoprim are both eliminated primarily by renal excretion, both by glomerular filtration and tubular secretion. Urine concentrations of both sulfadiazine and trimethoprim are several-fold higher than blood concentrations.1 Sulfadiazine and trimethoprim are 20% and 35% bound to plasma protein, respectively. Administration of sulfadiazine and trimethoprim with food has no apparent effect on the absorption of sulfadiazine but the absorption of trimethoprim is decreased. Based on a study in fed horses, trimethoprim concentrations following repeat oral administration of 24 mg/kg EQUISUL-SDT to 6 horses reached peak concentration in 0.5 to 12.0 hours. The median plasma elimination half-life was 3 hours, with a range of 2.31 to 4.96 hours. Peak sulfadiazine concentrations were reached within 1.0 to 12.0 hours in the same study. The median plasma elimination half-life for sulfadiazine was approximately 7.80 hours, with a range of 6.78 to 10.39 hours. Only minor accumulation of both drugs was observed following repeat oral administration of EQUISUL-SDT and both drugs reached steady state by day 3. Sulfadiazine and trimethoprim key steady state parameters associated with administration in 6 fed horses over a period of 7 days are found in Table 2. Table 2. median (Range) of sulfadiazine and trimethoprim pharmacokinetics parameters following repeat dosing of 24 mg/kg bid EQUISUL-SDT for 7 days to six horses in fed condition Drug

Sulfadiazine

Trimethoprim

Tmax (hr)

4.75 (1.00–12.00)

8.50 (0.50–12.00)

Cmax (µg/mL)

17.63 (10.10–31.15)

0.78 (0.60–1.14)

AUC 0–12 (last dose) (hr*µg/mL)

159.35 (73.90–282.54)

5.47 (3.31–10.91)

7.80 (6.78–10.39)

3.00 (2.31–4.96)

T 1/2 (hr)

mICRObIOLOgy EQUISUL-SDT is the combination of the sulfonamide sulfadiazine and trimethoprim. These two drugs block sequential steps in nucleic acids biosynthesis. Sulfadiazine inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid. Trimethoprim blocks the production of tetrahydrofolic acid from dihydrofolic acid by reversibly inhibiting dihydrofolate reductase. The two drugs act synergistically, reducing the minimum inhibitory concentration of each, while enhancing the bacteriostatic action of each separately to a bactericidal action when combined. EQUISUL-SDT administered as a combined sulfadiazine-trimethoprim dose of 24 mg/kg body weight twice daily for 7 days provided concentrations of sulfadiazine and trimethoprim with T>MIC90 (%T) values of 100% and 98% respectively. The minimum inhibitory concentration (MIC) values for EQUISUL-SDT against indicated pathogens isolated from lower respiratory tract infections in horses enrolled in a 2010–2011 effectiveness field study are presented in Table 3. All MICs were determined in accordance with the Clinical and Laboratory Standards Institute (CLSI) Approved Standard M31-A3 using a broth microdilution system and 3% lysed horse blood. Table 3. Trimethoprim/sulfadiazine minimum inhibitory concentration a (mIC) values of isolates recovered from horses with lower respiratory infection caused by Streptococcus equi subsp. zooepidemicus treated with EQUISUL-SDT in the U.S. (2010–2011) Treatment Outcome Number of Isolates Time of Sample Collection

Success c 65

Failure

Table 4 summarizes the statistical analysis results on the overall success rate. Table 4. Overall Clinical Effectiveness Results

Least Square Means

Equisul-SDT

Saline

P-value*

61%

13.1%

0.0123

* P-value and estimated success rates are based on back-transformed mean estimates from the statistical analysis. ANImAL SAFETy In a target animal safety study, EQUISUL-SDT was administered orally to 32 healthy adult horses at 0 (0X), 24 (1X), 72 (3X), or 120 (5X) mg/kg twice daily for 30 days. Loose stool was the most common abnormal observation. Observations of loose stool (pellets with liquid or unformed/cowpile stool) occurred more often in horses treated with EQUISUL-SDT with the incidence of loose stool increasing in a dose related manner. All incidents of loose stool were self-limiting and resolved without treatment. Horses in all EQUISUL-SDT groups demonstrated statistically significantly higher mean serum creatinine concentrations, and those in the 3X and 5X groups demonstrated statistically significantly higher mean serum albumin concentrations. Statistically higher mean neutrophil counts and mean serum gamma glutamyl transferase (GGT) activity were seen in the 1X and 5X groups. Individual animal creatinine, GGT, and albumin concentrations remained within the reference range. Individual animal elevations in absolute neutrophil counts ranged up to 7.09 x 103/mcL (reference range: 1.96-5.31 x 103/mcL). Based upon blood concentrations obtained during the study, it was noted that the sulfadiazine and trimethoprim plasma concentrations did not increase in proportion to dose. For sulfadiazine, a 3X and 5X dose resulted in an average exposure of 2.0X and 2.6X the concentrations observed following a 1X dose. For trimethoprim, the corresponding values were 2.5X and 3.5X as compared to the 1X dose. Furthermore, marked intersubject variability, particularly with sulfadiazine, resulted in substantial overlap of individual subject blood levels across the three dosing groups. STORAgE CONDITIONS Store at 59°– 86° F (15°– 30° C). Brief periods up to 104° F (40° C) are permitted. Protect from freezing. HOW SUPPLIED EQUISUL-SDT is available in the following package sizes: 135 mL 280 mL 560 mL 900 mL

Pre-Treatment

MIC 50b (µg/mL)

0.25/4.75

MIC 90b (µg/mL)

0.25/4.75

0.12/2.4 to 0.5/9.5

MIC Range (µg/mL)

EFFECTIvENESS A negative control, randomized, masked, field study evaluated the effectiveness of EQUISUL-SDT administered at 24 mg/kg body weight, orally, twice daily for 10 days for the treatment of lower respiratory tract infections in horses caused by Streptococcus equi subsp. zooepidemicus. In this study, a total of 182 horses were treated with EQUISUL-SDT, and 88 horses were treated with saline. One hundred seventy-three horses (112 EQUISUL-SDT and 61 saline) were included in the statistical analysis. Therapeutic success was characterized by absence of fever and no worsening of clinical signs at Day 5 and Day 10, and significant clinical improvement or resolution of clinical signs of lower respiratory tract infection by Day 17. The observed success rates are 58.9% (66/112) and 14.8% (9/61) for the EQUISUL-SDT and saline-treated groups, respectively.

a The correlation between in vitro susceptibility data and clinical effectiveness is unknown. b The lowest MIC to encompass 50% and 90% of the most susceptible isolates, respectively. c One isolate of S. equi subsp. zooepidemicus was not tested.

[footnote] 1 Kahn CM, Line S, eds. The Merck Veterinary Manual. 10th Ed. Merck & Co. 2010.

3. Oral soft tissues

Keep an eye out for lesions associated with the mucosa of the lips, the commissure of the lips, the bars of the oral cavity, or lesions associated with hardware that show or sporting horses wear for performance. Lesions should also be cross-checked with the type of tissue involved. “I recently saw a horse with a full-thickness lesion through the dorsal surface of the tongue,” Dr. Henry said. “That’s keratinized tissue. It’s very tough. If I see something that’s causing significant trauma [to that type of tissue], then I am going to be concerned. It turned out that the horse had been eating grain off of the ground in a place that had a lot of broken glass lying around.” For common lesions of the less rugged buccal mucosal tissue, the problem can often be resolved by removing the source of the trauma.

4. Periodontal status

The periodontia includes the gingiva, gingival sulcus, periodontal ligament, the cementum of the tooth, and the alveolar bone. Periodontal disease is often painful for the horse, so local anesthesia may be needed to complete the examination. An eagle eye is also helpful for this portion of the examination, Dr. Henry said. “You really have to use your mirror and look closely at the tooth, because you can’t get your head where it needs to be to see everything. I once removed some calculus with a scaler in a patient and noticed a small entrance to a draining tract. The horse had an abscess at the apex of this tooth that drained back into the periodontia and into the mouth. That tract probed to about 50 mm.”

5. Endodontic status

The crux of the endodontic evaluation is the determination

Patient Prep and a Trusty Bucket “I have been performing oral examinations for more than 20 years, but it still scares me,” Travis J. Henry, DVM, said. “Every time I sedate a horse, I need to look in the mouth and I need to find everything that I can.” Dr. Henry emphasized that it is important to remember that there is a body connected to the horse’s mouth, so a physical examination is mandatory. “Many of my patients are elderly, so I need to make sure it is safe to sedate them,” he said. “You need a full mouth speculum and you need to rinse debris from the oral cavity. A lot of the things we are looking for are small, subtle changes that can lead to future problems, so you need to see what’s behind the debris.” Dr. Henry’s chosen disinfectant is a bucket of chlorhexidine gluconate that is diluted until it is light blue. The chlorhexidine does not irritate oral tissue and it provides sanitization for the instruments between horses. It also keeps things in focus. “Mouth mirrors often fog in the oral cavity,” he said. “When you buy a new mirror, put it in the chlorhexidine gluconate solution and then let it dry. Every time you place the mirror back in that bucket, it’s going to keep that film on the mirror and prevent it from fogging.” Shutterstock/Nata-Lia

The crux of the endodontic evaluation is the determination of crown integrity and the search for fractures or any changes on the occlusal services. of crown integrity and the search for fractures or any changes on the occlusal surfaces of the teeth. Dr. Henry recommended performing this part of the examination systematically. Start with the same

quadrant in each horse, and move in a repeatable pattern. Dr. Henry’s practice uses a standardized chart that holds all of the oral findings. Every finding has a box to check. There is an area to draw malocclusions, an area for periodontal and endodontal status, and a space to formulate the list of oral problems. “For years I would look in a horse’s mouth and stop the examination when I found something wrong,” he said. “It is important to go through each patient in the same manner. Early in my career, I saw a horse with left-sided nasal discharge. I found a large, complicated crown-root fracture, and I stopped the examination. That horse had problems after a few months, and I ended up finding an exposed pulp horn of the second premolar that I missed on the first examination. Even though you find the big one, you should keep looking systematically and keep checking those boxes.” MeV ModernEquineVet.com | Issue 5/2015

infectious disease

Nothing to

sneeze at Low dose TMP/SDZ effective against Strep zoo

B y 10

Issue 5/2015 | ModernEquineVet.com

and it has a fairly broad spectrum, so it is an important part of the veterinarian’s armamentarium. However, to maintain effective minimum inhibitory concentrations (MICs) that fight infection, it is best to dose the product twice a day, which could increase the likelihood of diarrhea using the original paste, he explained. The FDA approval of the new formulation was based on several safety and bioequivalency studies, Dr. McClure said. A bioequivalency study found that with the oral suspension, SDZ CMAX serum concentration was 176% of the oral paste and the TMP CMAX serum concentration was 127% of the oral paste when both were dosed equally at 30 mg/kg.

K a t h l e e n

“Subsequently it was identified that with this suspension, the dose could be decreased 20% and obtain the same serum concentration of the active ingredients,” he said, adding, “with the benefit of less exposure of the intestinal flora to the antimicrobials.”

Safety study

To study the safety of the TMP/ SDZ oral suspension, horses were treated with one, three and five times the 24 mg/kg dose for 30 days, which is three times the recommended 10-day dosing. The study, which was published last year in the Journal of Veterinary Sciences, showed that the oral suspension was

O g l e

Photo credit: bob@boblangrish.co.uk

Trimethoprim/sulfadiazine is a common treatment for respiratory infections among horses; however, the side effect most often reported after using TMP/SDZ is diarrhea, which has its own set of problems. A new oral suspension (EquisulSDT, Aurora Pharmaceutical) has an improved bioavailability, which means that horses can receive lower doses. The lower doses, which still effectively treat lower respiratory tract infections caused by Streptococcus zooepidemicus, are associated with less diarrhea, according to Scott McClure, DVM, PhD, DACVS, associate professor at Iowa State University, at the 60th annual convention of the American Association of Equine Practitioners. “We are all familiar with trimethoprim sulfa. We are all using trimethoprim sulfa. But this is a new solution that has some different pharmacokinetics,” Dr. McClure said. “This is dosed differently than the trimethoprim sulfas we are used to using and the advantage of that, is having more absorption and less of the material getting by into the large colon.” TMP/SDZ is one of the few oral antibiotics available for the horse

well tolerated at up to five times the recommended 24 mg/kg dose. Noting that diarrhea is a major concern when using antimicrobials, Dr. McClure reported loose feces was the most common observation related to TMP/SDZ treatment, and the incidence of loose feces was greater in groups treated with the three and five times dosages of TMP/SDZ. “However, all episodes were mild and self-limiting, and no horses were treated for loose feces,” he said.

Efficacy study

To study the efficacy of the TMP/SDZ oral suspension in horses with lower respiratory tract infections caused by S. zooepidemicus, Dr. McClure and his colleagues conducted a randomized, blinded, placebo-controlled multicenter study of naturally occurring bronchopneumonia in investigator-owned horses. As the horses developed respiratory disease they were evaluated daily until they met the criteria for enrollment (temperature ≥ 101⁰ F, respiratory rate ≥ 24 breaths/min, abnormal auscultation without rebreathing, and an intermittent, spontaneous cough). Horses that met the clinical criteria underwent a trans tracheal wash to confirm the presence of S. zooepidemicus. Then the horses were started on 24 mg/ kg of the oral suspension twice a day for 20 treatments (67 mg/mL TMP and 333 mg/mL SDZ = 400 mg/ kg). After 10 days, the horses were followed for another seven days to see if they would relapse before they reached the end of the study period. Horses in the placebo group were administered saline, equivalent volume and timing, and blind-

A horse with respiratory issues. Source: Courtesy of Dr. S. McClure

ing was maintained by differences in personnel and observers,” Dr. McClure said. “Any material that may have been left on the mouth or lips was wiped off.” Complete physical exams were done on days 0, 5, 10 and 17 with twice daily observations of feed intake and feces through day 17. Blood samples were taken initially and at the completion of the study, or when the horse reached a failure criteria. The trans tracheal wash was repeated when the horse failed or reached the end of the study, Dr. McClure said. Treatment was considered a success when there was a temperature drop of 2⁰ or the temperature was < 101⁰ F, the respiratory rate was < 24 breaths/min and auscultation was normal within five days of treatment. A horse was allowed to have an intermittent cough at days 5 and 10 but no cough by day 17, he said.

Of the 270 horses enrolled in the study, 180 horses underwent the trans tracheal wash: 119 received treatment and 69 were considered successes (59%); 61 received placebo, of which 9 were considered successes (15%), Dr. McClure reported. “Treatment failures occurred early on,” Dr. McClure said, with most of the treatment failures in the TMP-SDZ group (5/119 or 6%) occurring by day 5 (25/61 or 41% in the control group), with a few more occurring by day 10 (28/61 or 46% in the control group; 11/112 or 9.2% in the TMP/SDZ group). “Overall, the elimination of strep zoo was 66% in the treated group (75/116) compared with only 21% (12/56) in the untreated group so the antimicrobial was effective in eradicating the strep zoo organism,” Dr. McClure said. He reported a total of 17 adverse events with 10 in the 182 treated horses and 7 in the 88 control horses. There was no significant difference in diarrhea between the two groups with 38% of the treated horses having loose stool at some point in the study period compared with 33% of the saline-treated horses. “So what we found in this study was 24 mg/kg administered twice a day was effective in treating S. zooepidemicus bronchopneumonia in this group of horses. I think it was stringent from the standpoint that they had to meet the improvement criteria at days 5 and 10 and no relapse by day 17,” Dr. McClure concluded. “The other thing that was good was we didn’t see diarrhea in these horses. We didn’t have any complications or adverse events. So we can decrease the dose, have less in the large colon and maintain our effectiveness.” MeV

For more information: Reinemeyer C, Koenig R, Hawkins PA. A Controlled safety study of elevated dosages of trimethoprim plus sulfadiazine in mature horses. J Equine Vet Sci. 2013 2014;34:626-631. http://www.j-evs.com/article/S0737-0806(13)00929-5/abstract ModernEquineVet.com | Issue 5/2015

dermatology

Encapsulated Stem Cells A c c e l e r at e W o u n d H e a l i n g M e r r y

R .

B u c k l e y

Stem cells confined inside tiny capsules secrete substances that help heal simulated wounds in cell cultures, opening up new ways of delivering stem cells to locations in the body where they can hasten healing. 12

Issue 5/2015 | ModernEquineVet.com

The capsules need to be tested to see if they help healing in animals and humans, but they could eventually lead to “living bandage” technologies: wound dressings embedded with capsules of stem cells to help the wound regenerate,

according to the researchers. “The encapsulation seems to increase the stem cells’ regenerative potential,” said Gerlinde Van de Walle, DVM, PhD, assistant professor of viral pathogenesis, the Baker Institute for Animal

Source: Cornell University

Mesenchymal stem cells captured in microcapsules. Each microcapsule is roughly 40 µm across.

Health at the Cornell University College of Veterinary Medicine, adding that the reasons why are not yet known. “It's possible that putting them in capsules changes the interactions between stem cells or changes the microenvironment.”

Sharing similarities to humans

To her knowledge, Dr. Van de Walle said, this is the first time encapsulated stem cells have been used to treat wounds. Her team used equine stem cells and cell cultures because, unlike mice, the healing process in horses shares important similarities with the healing process in humans and because wound healing in horses is a particularly difficult problem in veterinary medicine. Mesenchymal stem cells are adult stem cells that can be isolated from different parts of the body, and it’s long been known that they secrete substances that aid in tissue healing. Problems arise when trying to use these stem cells in real patients, Dr. Van de Walle said, because they often won’t stay put in the healing area and can occasionally form tumors or develop into unwanted cell types. She and her team began exploring the possibilities of encapsulating these cells as a way of avoiding these pitfalls. The capsules help cells stay in place while they secrete substances into the wound and can be removed easily if the stem cells would develop in an adverse way. The researchers collaborated with Mingling Ma, PhD, of the Department of Biological and En-

vironmental Engineering and his laboratory to create the coreshell hydrogel microcapsules around the stem cells. Dr. Van de Walle said she was excited to see that the capsules did not abolish the stem cell properties but instead appeared to enhance the beneficial effects the stem cell secreted products have on tissue cultures. This suggested that encapsulating the stem cells for wound healing not only avoids certain problems, it can boost the effectiveness of treatment.

to back up many of these uses are lacking. Dr. Van de Walle hopes to shed some light on an area that is poorly understood. This new work shows microencapsulated stem cells have a great deal of promise, said Ms. Harman, but there’s a lot to do before they could be embedded in bandages and used in hospitals or veterinary clinics. Since skin is a complex organ, the approach needs to be studied in a variety of cell culture systems before testing on humans or horses.

Encapsulating the stem cells for wound healing appears to boost the effectiveness of treatment. With their mesenchymal stem cell work, Dr. Van de Walle and her colleagues are trying to understand the basic science behind the regenerative abilities of these cells. The researchers found that the MSCs stimulated the migration of healing equine dermal fibroblasts, increasing their gene expression. “Currently many equine veterinarians are using stem cells for therapy, but the mechanisms in which they work—and their potential—haven’t been fully explored,” said co-researcher Rebecca Harman, a graduate student at the Baker Institute. Stem cells can be used in horses without much regulatory oversight, but studies

“Going in vivo is the ultimate goal, but there’s still work to be done in vitro. We're expanding our cell culture experiments to include other cell types present in MeV skin,” Ms. Harman said.

About the author: Merry R. Buckley is education and outreach program coordinator for the Baker Institute for Animal Health and the Cornell Feline Health Center. Read more about Cornell University at www.vet.cornell.edu

For more information: Bussche L, Harman RM, Syracuse BA, et al. Microencapsulated equine mesenchymal stromal cells promote cutaneous wound healing in vitro. Stem Cell Research & Therapy 2015;6:66. http://stemcellres.com/content/6/1/66 ModernEquineVet.com | Issue 5/2015

AAEV T M E M b E r s h i p Membership in the AAEVT is open to all veterinary technicians, assistants, support staff and those employed in the veterinary health care industry worldwide. Student membership is open to those currently enrolled in an AVMA/CVMA accredited veterinary technology program.

AAEVT Membership • • • • • • • • • • •

Bi-Annual Newsletter Weekly “HoofBeats” Email Newsblast Full access to www.aaevt.org, including the Career Center and the Library Up-to-date information on the AAEVT Discounted registration for AAEVT Regional Meetings and the annual AAEP/AAEVT Convention NTRA, Working Advantage and Platinum Performance Benefits The opportunity to participate in the AAEVT Online Certification Program or to become a member of the AEVNT Academy-Specialty in Equine Veterinary Nursing Scholarship opportunities. AAEVT’s Equine Manual for Veterinary Technicians (Blackwell Publishing 20% discount on purchase price) Opportunity to attend Purina’s Annual Equine Veterinary Technician Conference - All Expenses paid!

AAEVT Objectives • • • •

Provide opportunities for CE, training, communication, and networking Educate the equine veterinary community and the public about our profession Inform Members of issues affecting our profession Assist in providing the best medical care to improve the health and welfare of the horse

AAEVT Online Equine Certification Program

• A three course, 10 module, equine-only online program offered through ACT • Geared toward Credentialed Veterinary Technicians, Assistants, Support staff, & Students • Areas of study include: equine medical terminology, anatomy and physiology, parasitology, laboratory, diagnostics, equine basics (breeds, wellness, husbandry,) diagnostic procedures, emergency medicine, restraint, pharmacology, surgical assistance and anesthesia, equine office procedures • A certificate of completion is awarded to those who: Successfully complete required courses Complete the list of required skills (per a supervising DVM who is an AAEP member) Attend an AAEVT regional CE symposium and participate in the we labs • Those individuals who successfully complete the programs will be recognized as AAEVT Certified Equine Veterinary Technicians / AAEVT Certified Equine Veterinary Assistants depending on their current designation. The certificate is recognized by the AAEVT and the AAEP but does not grant the credentialed status by the AVMA • For more information go to www.aaevt.4act.com or call 800-357-3182

AAEVT Mission Statement: To promote the health and welfare of the horse through the education and professional enrichment of the equine veterinary technician and assistant.

Fo r m o re i n f o r m a t ion v ist w w w.a ae vt.or g

*American Association of Equine Veterinary Technicians and Assistants

technician update

By Deborah Reeder, RVT, VTS-EVN There is little doubt that equine practitioners face some unique challenges in their practices that small animal veterinar-

ians do not face. For instance, the critical issue of obtaining the consent to treatment from the owner becomes blurred when the equine clinician regularly accepts instructions from a trainer or stable manager. It is important for the proper management of the equine practice to make sure that the actual owner of the horse is both identified and provides specific instructions that the trainer is authorized to act on the owner’s behalf. Too often the equine practice is compromised when the owner refuses to pay for services on the basis that the instructions to provide service were never actually authorized by the owner. During the initial engagement, the veterinarian should ensure that the trainer or other designated party can provide authorization. This is particularly important when the ownership of the animal may be held by a number of entities through a form of syndication. Communication is the key factor in the success of any service business. Veterinary medicine is no exception and the clients’ interactions with the practice can be the most important factor in the success or failure of a practice. Every day there are communications with the backyard owner of a single horse, multiple owners of million-dollar racing Thoroughbreds, buyers, sellers, agents, referring veterinarians, barn managers, trainers, riders, insurance companies, an export agent, a show

office, the Department of Agriculture or a farrier. To protect the practice and the individuals working for the practice, all of these communications must be documented. Consistent and timely communication among staff is a challenge, which must be met if the practice is to run smoothly. Make sure that complete and correct messages are delivered promptly to the appropriate person and are followed up quickly. This will go a long way toward reassuring clients that their requests are being well-handled. Confidentiality when dealing with client information is an absolute necessity, which, if not strictly adhered to, can result in the loss of a client or practice reputation at the minimum or a lawsuit attacking professional ethics. Medical Records are the practice’s communication between staff and the client. Creating and maintaining correct, accurate and timely medical records is the single most important responsibility of the equine technician in a practice. Accurate medical records, completed in a timely fashion, are a legal necessity and the only protection against successful malpractice litigation. The challenges associated with obtaining and recording this information must be met. Ethically, the information within veterinary medical records is considered privileged and confidential.

Shutterstock/Rob Byron

Medical Records in the Equine Practice— How to Reduce RISK

ModernEquineVet.com | Issue 5/2015

technician update It must not be released except by court order or consent of the owner of the patient. This is especially true when horses change owners or are presented for a prepurchase examination, as the absolute confidentiality of information must be maintained and prior medical history cannot be included in the medical record or communicated to a second owner or potential buyer without the express written permission of the original owner. It is important to note that the physical images (radiographs, ultrasound images or bone scan images for instance) are the property of the practice, which created them. The information contained in these images is the property of the client who paid for them to be made. Release of this information requires a signed release from that client. Absolute adherence to this law is essential. The length of time that patient records, including imaging, must be maintained by a practice, regardless of the status of the patient, varies from state to state; however, a minimum of 10 years provides a good rule-of-thumb. Medical Records should contain the minimum standards of information collected and documented, including a complete and thorough description of the horse, it’s age and weight, its use, identifiable markings or tattoos, breeding history if relevant, and any medical history, such as medications, feed and supplements. Complete client information should be documented, and information collected that indicates the practice has done due diligence in assuring ownership/ agency authorization of the horse. The physical examination should be recorded and should include notations on normal findings as well as any abnormalities. In addition, the following should always be included in any medical record for any visit or examination and noted as to day, time and person performing the procedure: • Presenting complaint(s) • Diagnostic recommendations

• Treatment provided • Prognosis, if indicated • Written and oral client communication • Authorizations to treat as well as the declining of any recommended procedures • Notation of any educational materials given to clients All conversations need to be noted in the medical record, whether it be in person, via the phone, email, fax, text or a voicemail message. Time and day should be noted and include the initials of the person who was involved in the communication. The saying that often comes up in a court case is “If it is not in the medical record….it did not happen.” The records should be consistent in the information collected, the format, and they should be legible. If they cannot be easily read or deciphered, they will be thrown out in any court or State Board case. Do not include any editorial comments and make sure that any corrections done are noted that they are a correction and why. The more information collected the better. Have your practice perform a records audit at least twice a year and discuss ways you can reduce your risk through better management of your medical records. MeV Thanks to Doug Jack—Solicitor/Legal Counsel AVMA and Dr. Andrew Clark, DVM, MBA for source information.

About the author

Deborah Reeder, RVT, VTS-EVN, is the executive director of the American Association of Equine Veterinary Technicians and the Academy of Equine Veterinary Nursing Technicians. For information about joining these organizations, click on the ad on page 14.

Issue 5/2015 | ModernEquineVet.com

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news notes

Sarcoids remain most common tumor among horses Sarcoids remain the most commonly identified tumor type among horses, according to a recent study out of the United Kingdom. Increasing age was significantly associated with the odds of lymphoma, melanoma, gonadal stromal tumor, mast cell tumor and in particular squamous cell carcinoma. Some interesting breed and sex associations were identified in an observational study that surveyed equine tumor samples submitted to The University of Bristol diagnostic pathological laboratory over a period of 29 years (1982â&#x20AC;&#x201C;2010).

with mares. A wider range of breeds were represented in later study years. Some breed associations were found, namely Arab/Arab X with mast cell tumors, ponies with melanomas and Cobs/Cob X with squamous cell carcinoma and mast cell tumors. MeV

Study looks at horse tendons ability to recover

Older age increased the odds of certain tumors. The survey included 964 cases and examined changes in odds of diagnosis, breed or gender associations and any changes in tumor types diagnosed over time. The most commonly diagnosed tumor type was the sarcoid (24% of tumor samples), squamous cell carcinoma (19%), lymphoma (14%), melanoma (6%), gonadal stromal tumor (6%) and mast cell tumor (4%). The relatively low proportion of sarcoids diagnosed may be due to population factors or clinician habits. For example, confidence in clinical diagnosis alone could reduce the numbers referred for laboratory confirmation, the researchers said. Over the period, the proportion of tumors diagnosed as sarcoids and lymphoma decreased. There was no significant difference in the proportions of the other four main tumor types over time, although less common tumor types appeared to be overrepresented in later years of the study. The mean age of horses from which samples were submitted was significantly higher in the 2000s than in the â&#x20AC;&#x2122;80s or â&#x20AC;&#x2122;90s, indicating a general trend toward increasing age in the population studied. For all of the main tumor types except sarcoids, age increased the odds of diagnosis, particularly in squamous cell carcinoma. Geldings were found to be at a significantly increased risk of squamous cell carcinoma compared

For more information: Knowles EJ, Tremaine WH, Pearson GR, Mair TS. A database survey of equine tumors in the United Kingdom. Equine Vet J 2015 Jan 15. doi: 10.1111/evj.12418. [Epub ahead of print]. http://onlinelibrary.wiley.com/doi/10.1111/evj.12421/abstract

This is a histology image showing the interfascicular matrix. Photo courtesy of C Thorpe/QMUL

Stiffening in aging tendons contributes to increased injuries in tendons. New research shows that the responsibility lies in the decreased resistance to repetitive loading of the tissue that holds tendon fiber bundles in place. Researchers from Queen Mary University of London (QMUL), University of East Anglia, University College London and University of Liverpool, repeatedly stretched samples of horse tendons, which are similar to human ones, to test their elasticity and ability to recover. Tendon fiber bundles are surrounded by the interfascicular matrix (IFM), made up of tissue which enables the fiber bundles to slide past each other and stretch independently. In horses, the superficial digital flexor tendon (SDFT), which is used to store energy for propulsion, requires greater stretching of the IFM, than in the common digital extensor tendon (CDET) which aids the positioning of the leg. While the IFM is more elastic, recovering better after loading in the SDFT, it is prone to injury in older age because of the greater strain it is put under, and the stiffening and decreased ability to recover that results after use. The SDFT is very similar to the human Achilles tendon and so the results of this study can be directly applied to Achilles injury in humans, the researchers explained. This new discovery implies that injuries to different tendons could be treated differently and that new treatments could be MeV developed to prevent injuries in older individuals.

For more information: Thorpe CT, Godinho MSC, Riley GP, et al. The interfascicular matrix enables fascicle sliding and recovery in tendon, and behaves more elastically in energy storing tendons. J Mech Behav Biomed Mater 2015; DOI: 10.1016/j.jmbbm.2015.04.009

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