The Modern Equine Vet - July 2020 by The Modern Equine Vet

The Modern

Equine Vet www.modernequinevet.com

When to Refer a Colic

Vol 10 Issue 7 2020

Ask the Nutritionist? Best Diet for Horse with Chronic Colic Valcyclovir and Heparin for EHM Smarter Smart Phone: Stall-Side ECG

CHECK OUT: ASK THE NUTRITIONIST? YOUR NUTRITION QUESTIONS ANSWERED

TABLE OF CONTENTS

COVER STORY

4 When to Refer a Colic Cover: Shutterstock/Marie Charouzova

ASK THE NUTRITIONIST

What Nutritional Strategies Can Be Used to Support Horses Experiencing Chronic Colic?........................................................................... 3 INFECTIOUS DISEASES

Valacyclovir and Heparin May Improve Survival in Horses with EHM ........................10 CARDIOLOGY

Smarter Smart Phone: Stall-side ECG .....................................................................................13 MORE THAN A HITCHING POST

Find Your Passion!...........................................................................................................................14 NEWS NOTES

Cannabinoid Receptors Present in Equine Nerve Cells ....................................................... 9 Antibiotic Alternative for R. Equi Prophylaxis.......................................................................12 ADVERTISERS Purina Sponsored Content.........................................3 American Regent Animal Health/Adequan...........5 iStat Zoetis....................................................................7

AVMA PLIT......................................................................9 Epicur Pharma............................................................11 AAEVT............................................................................13

The Modern

Equine Vet SALES: Matthew Todd • Lillie Collett EDITOR: Marie Rosenthal ART DIRECTOR: Jennifer Barlow CONTRIBUTING WRITERS: Paul Basillo • Adam Marcus 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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Ask the

Nutritionist DR. ROBERT JACOBS, PH.D., EQUINE INNOVATION MANAGER, PURINA ANIMAL NUTRITION

Ask the Nutritionist is a monthly column featuring questions answered by PhD equine nutritionists and sponsored by Purina Animal Nutrition. Have a nutrition question you want to see featured? Email Marie Rosenthal. For clinics looking for specific nutritional advice, visit purinamills.com/ask-an-expert.

What nutritional strategies can be used to support horses experiencing chronic colic symptoms? Dealing with horses experiencing chronic colic or repetitive colic episodes can be highly frustrating for both owners and veterinarians. Many conditions—including gastric ulcers, enteroliths, uroliths and others—may result in frequent bouts of colic. Horses should be screened for these conditions and treated appropriately. However, many cases of chronic colic require changes to the horse’s diet. Nutritional management can help to reduce or even eliminate chronic colic episodes. These guidelines can serve as a starting point for managing each unique case: • Consistent feeding practices • Slow dietary changes • High-quality forage • Complete feeds • Gastric support

chronic, colic-like symptoms may require a longer transition than other horses. The average transition period between the old feed or forage and the new feed or forage should be at least 5 to 7 days. An even more conservative rule of thumb for sensitive horses is to make the change at a rate no faster than 1 pound of new feed per day. COMPLETE FEEDS In some cases, replacing all or a portion of longstemmed hay with an easily digestible complete feed, like Purina® Equine Senior® horse feed can reduce the frequency of colic bouts. If a more calorically dense complete feed is needed, try Purina® Omolene 400® horse feed. When fed as a complete feed, these feeds should be supplied at 1.5 – 2.0% of bodyweight daily and offered in small, frequent meals.

CONSISTENT FEEDING A stable and consistent diet is crucial in maintaining gastrointestinal health. Consistently feeding small, frequent meals is important to support optimal gastrointestinal function. Feeding a high-quality concentrate can also help. FORAGE QUALITY Forage consistency, whether hay or pasture, is often a critically overlooked component of the diet. Pasture and hay analyses allow you to fully understand the forage’s nutritional contribution to the diet. A good-quality grass hay can decrease the risk of digestive upset, so look for hay with a relative feed value (RFV) > 87, an acid detergent fiber (ADF) < 42 (as fed basis) and a neutral detergent fiber (NDF) < 60 (as fed basis). If quality forage is not available, forage alternatives such as hay cubes, hay pellets or hay stretcher products like Purina® Impact® Hay Stretcher can offer more nutritional consistency and serve as a full or partial forage replacement. DIETARY CHANGES Changes to the diet should occur slowly over time for both the concentrate portion of the diet as well as the forage component. Horses that experience

GASTRIC SUPPORT Gastric discomfort can also be a cause of chronic colic. Continual access to forage that includes some alfalfa can help to manage gastric discomfort and mitigate the risk of developing or worsening gastric ulcers. Feeding Purina® Outlast® Gastric Support Supplement supports gastric comfort by promoting optimal gastric pH, and it can be offered with meals and as a snack prior to exercise and stressful events. Ensuring the pH of the horse’s stomach remains at an optimal level for prolonged periods can help to support overall gastric health and comfort in the horse. Contact a Purina PhD nutritionist for a complimentary consultation through Purina Customer Service, 800-227-8941 or send us a message at www.purinamills.com/ask-an-expert.

UPCOMING TOPICS August: Lameness September: Cardiology October: Reproduction

Have a question you want to see featured? Send them to modernequinevet@gmail.com.

ABOUT THE AUTHOR Dr. Robert Jacobs, Ph.D., is the Equine Innovation Manager at Purina Animal Nutrition. He is responsible for conducting research aimed at better understanding how nutrition impacts various areas of equine physiology. SPONSORED BY PURINA ANIMAL NUTRITION

ModernEquineVet.com | Issue 7/2020

COLIC

When to

Refer a Colic? Shutterstock/gibleho Shutterstock/Marie Charouzova

Early Referral, Faster Intervention Improves Colic Prognosis

A standardized work up that leads to a faster referral greatly increases a horse’s survival from colic, according to Barbara L. Dallap Schaer, VMD, DACVS, DACVECC, professor of emergency medicine and critical care and medical director at the University of Pennsylvania’s School of Veterinary Medicine (Penn Vet) New Bolton Center, Kennett Square, Pa. “It is a really important thing to explain to your clients that the survival for surgical colic has indeed changed dramatically,” she said. B y

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In the early ’80s, survival from a surgical colic “was less than a coin toss,” Dr. Dallap Schaer admitted. “Today, most institutions that offer colic surgery see around a 90% survival rate. But the opportunities to help a colicking horse can only begin when the client picks up the phone and says, ‘I have a problem,’” she said. The standard colic work up in the field usually consists of a careful physical examination focused on how toxic the horse appears; abdominal palpation per rectum and passing a nasal gastric tube to check for reflux. Ultra-

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There’s nothing else like it. Over the past 30 years, Adequan® i.m. (polysulfated glycosaminoglycan) has been administered millions of times1 to treat degenerative joint disease, and with good reason. From day one, it’s been 2, 3 the only FDA-Approved equine PSGAG joint treatment available, and the only one proven to. Reduce inflammation Restore synovial joint lubrication Repair joint cartilage Reverse the disease cycle When you start with it early and stay with it as needed, horses may enjoy greater mobility 2, 4, 5 over a lifetime. Discover if Adequan is the right choice. Talk to your American Regent Animal Health sales representative or call (800) 458-0163 to order. BRIEF SUMMARY: Prior to use please consult the product insert, a summary of which follows: CAUTION: Federal law restricts this drug to use by or on the order of a licensed veterinarian. INDICATIONS: Adequan® i.m. is recommended for the intramuscular treatment of non-infectious degenerative and/or traumatic joint dysfunction and associated lameness of the carpal and hock joints in horses. CONTRAINDICATIONS: There are no known contraindications to the use of intramuscular Polysulfated Glycosaminoglycan. WARNINGS: 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. PRECAUTIONS: The safe use of Adequan® i.m. in horses used for breeding purposes, during pregnancy, or in lactating mares has not been evaluated. For customer care, or to obtain product information, visit www.adequan.com. To report an adverse event please contact American Regent, Inc. at (800) 734-9236 or email pv@americanregent.com. Please see Full Prescribing Information at www.adequan.com.

www.adequan.com 1 Data on file. 2 Adequan® i.m. Package Insert, Rev 1/19. 3 Burba DJ, Collier MA, DeBault LE, Hanson-Painton O, Thompson HC, Holder CL: In vivo kinetic study on uptake and distribution of intramuscular tritium-labeled polysulfated glycosaminoglycan in equine body fluid compartments and articular cartilage in an osteochondral defect model. J Equine Vet Sci 1993; 13: 696-703. 4 Kim DY, Taylor HW, Moore RM, Paulsen DB, Cho DY. Articular chondrocyte apoptosis in equine osteoarthritis. The Veterinary Journal 2003; 166: 52-57. 5 McIlwraith CW, Frisbie DD, Kawcak CE, van Weeren PR. Joint Disease in the Horse.St. Louis, MO: Elsevier, 2016; 33-48. All trademarks are the property of American Regent, Inc. © 2020, American Regent, Inc. PP-AI-US-0372 02/2020

COLIC

common. “Typically if you reach over top and you trace the dorsal column mostly to your right, you're going to be able to feel cecal distension often far on the right. It can be difficult in some cases to DIAGNOSIS OF: actually palpate the cecum,” she • Right dorsal displacement advised. • Small intestinal distension It can also be difficult to distin• Nephrosplenic entrapment guish between cecal and colonic distension, although this is imporRectal Palpation EVIDENCE OF: tant, “because we treat the cecum Rectal palpation is extremely use• rupture or very differently than we treat the ful for assessing a horse in the field. • hemoabdomen colon. The cecum has a few very “It helps to visualize in your mind's specific anatomical features that eye what it is that you're looking Quick fluid check for abdominocentesis don't occur in the large colon; for. You might have a high index of Careful evaluation of foals and smaller probably the most important of suspicion of a particular lesion, and patients which is the dorsal body wall atthat might inform what you're feeltachment.” ing when you do your palpation,” “So if you can trace the distended viscous that you're Dr. Dallap Schaer suggested. She gave a couple of points palpating all the way, dorsal and palpate, that dorsal to consider when doing a rectal palpation. body wall attachment, you can pretty confidently say Nephrosplenic entrapment might be one of the that that is not the large colon.” most misdiagnosed lesions on rectal finding. “The Small colon impaction typically is not a diagnostic most salient feature on rectal palpation of nephrochallenge, but it is important to distinguish between splenic entrapment is a very large gas descending coa solid, very turgid distention versus a flaccid distenlon. It literally feels like someone has hung off the dortion. Most often it feels like an Anaconda snake runsal body wall,” she said. ning through the abdomen; it’s very solid, very turgid With a true nephrosplenic entrapment, it will be difand the diameter that you would expect from a small ficult, if not impossible, to feel the spleen, she warned. colon. “If you're palpating really thick and small intesRight dorsal displacement can come in “a few flatine on rectal exam, you can be pretty sure the horse is vors,” she said. There might be a 180° twist with colonic probably going to end up somewhere near a 10 blade at bands running transversely across the caudal aspect of some point,” she said. the abdomen. A moderate amount of gas distension is

What is Practical Sonographically in the Field?

Images courtesy of Penn Vet New Bolton Center

sonography and abdominocentesis can also provide diagnostic clarity and confirm the palpation results. There is an art to creating a siphon to collect reflux. “Although horses are very magical, spontaneous reflux is rare, and they cannot typically defy gravity,” added Dr. Dallap Schaer.

Dr. Louise Southwood, a veterinarian at PennVet New Bolton Equine Center in Pennsylvania, checks a horse after a successful colic surgery.

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COLIC

Another serious finding on palpation is intussusception, an invagination of the intestine, which frequently involves the ileum, although jejunal intussusceptions also occur.

Ultrasonography in a FLASH

mFLASH Simplified 1 . T he ventral abdominal window 2. The gastric window

To overcome this, Dr. Dallap Schaer suggested following that colon cranially for 5 to 6 intercostal spaces. 4. The duodenal window can help visualize small intestinal distention, distended vasculature and right dorsal displacement (RDD) of the large colon. 5. R DD will also be seen in the right middle third abdomen window. “If you see that running the whole way down the length of the course of the right body wall, both in window 4 and window 5, you can be pretty confident that you've got a right dorsal displacement,” she said.

3. The nephrosplenic Ultrasonography can help confirm window the palpation findings and can be performed quite readily in the field. 4. T he duodenal window She recommended an mFLASH, which is a modified fast localized 5. T he right middle third abdominal sonographic evaluation abdomen window of the horse. It is a simplified protocol that can be completed in about This modified mFLASH protocol can 10 minutes. The mFLaSH techbe completed in about 10 minutes, nique excludes the middle field simplifying the ultrasonography to get and thoraxic windows, simplifying a horse referred faster. the procedure to target surgical lesions to save time and refer a horse Abdominocentesis more quickly, if needed. Some veterinarians will perform abdominocentesis, “We wanted to try and help make a decision in which has some benefits, especially if one is trying to disthe middle of the night,” Dr. Dallap Schaer said. “The tinguish a proximal duodenitis/jejunitis from a strangumFLASH simplified the protocol and made it relalating small intestinal lesion. It is incredibly useful if there tively easy to complete in about 10 minutes so in a is a suspicion of peritonitis or ruptured viscus. practical field setting, this is certainly something that Perionteal lactate can be an important indicator. you could do.” Handheld lactate meters are fairly accurate and read1. The ventral abdominal window will help visuily available. “Certainly, if you have a peritoneal lactate alize a distended small intestine to find a stranthat's much higher than your peripheral lactate in your gulating versus a non-strangulating small intespatient, that's a reason to be concerned,” she said. tinal obstruction. It will be the most likely area But there are risks to abdominocentesis, most notaone would see a big thickened loop of a distended bly enterocentesis or splenic laceration. small bowel. One can also see a large colon volvu“I think some of the most salient things about when lus or a GI rupture. to refer a colicky horse relate to how sick your horse 2. The gastric window will help visualize a gastric is and what type of physiologic decline you have,” Dr. distension that would indicate a small intestinal Dallap Schaer said. obstruction. If there is physiologic decline and the horse looks re3. The nephrosplenic window is looking for nephroally toxic with tachycardia, tachypnea, hyperemic musplenic entrapment. Beware, however, if it is percous membranes, large volumes of reflux and clearly formed after a rectal palpation, there might be gas palpable abnormality on rectal exam, “You really need to start thinking about referring that patient. It's going in the colon, and it may give a false appearance of to be difficult to manage on the farm,” she said. MeV a distended gas filled viscus sitting on the spleen. For more information: Busoni V, De Busscher V, Lopez, D, et al. Evaluation of a protocol for fast localized abdominal sonography of horses (FLASH) admitted for colic. Vet J 2011;188(1):77-82. https://www.sciencedirect.com/science/article/abs/pii/S109002331000078X?via%3Dihub Setlakwe E. Prospective evaluation of the accuracy of the MFlaSh ultrasound protocol and transrectal abdominal palpation for predicting specific surgical diagnoses in cases of equine acute colic. 2015 ACVIM Forum Research Abstract Program J Vet Intern Med. 2015 Jul-Aug; 29(4): 1122–1256. Published online 2015 May 27. doi: 10.1111/jvim.12609. https://onlinelibrary.wiley.com/doi/10.1111/jvim.12609 8

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Shutterstock/StudioMolekuul

Cannabinoid Receptors Present in Equine Nerve Cells The use of medical marijuana and cannabinoid creams and ointments are gaining popularity in human medicine for their abilities to help alleviate some pain. The same might someday be true for horses. Researchers found cannabinoid receptors are present in the sensory neurons and glial cells of the dorsal root ganglia, which could be relevant for future functional studies assessing the effects of cannabinoids in horses to manage pain. A study out of Italy investigated the expression and location of cannabinoid receptors in the dorsal root ganglia, which could be a therapeutic target for pain. The cervical (C6-C8) dorsal root ganglia were collected from 6 horses (1.5 years old) at an abattoir and processed to obtain cryosections. Immunohistochemistry was used to localize the cellular distribution of cannabinoid receptors 1 (CB1R) and 2 (CB2R), and 3 other putative cannabinoid-related receptors: nuclear peroxisome proliferator-activated receptor alpha (PPARα), transient receptor potential ankyrin 1

(TRPA1) and serotonin 5-HT1a receptor (5-HT1aR). Cannabinoid and cannabinoid-related receptors were widely distributed in the sensory neurons and satellite glial cells of the dorsal root ganglia. The neurons showed immunoreactivity for CB1R (100%), CB2R (80±13%), PPARα (100%), TRPA1 (74±10%) and 5-HT1aR (84±6%). The neuronal satellite glial cells showed immunoreactivity for CB2R, PPARα, TRPA1 and 5-HT1aR. MeV

For more information: Chiocchetti R, Rinnovati R, Tagliavia C, et al. Localisation of cannabinoid and cannabinoid-related receptors in the equine dorsal root ganglia. Equine Vet J. 2020 Jun 11 [Epub ahead of print]. https://beva.onlinelibrary.wiley.com/ doi/10.1111/evj.13305

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INFECTIOUS DISEASES

Valacyclovir and Heparin

Shutterstock/acceptphoto

May Improve Survival in Horses with EHM

In recent naturally occurring outbreaks in Virginia of equine herpesvirus myeloencephalopathy (EHM), all horses that received treatment with valacyclovir and heparin survived, while horses that did not receive this combination were euthanized. Veterinarians from Marion duPont Scott Equine Medical Center, VA-MD Regional College of Veterinary Medicine at Virginia Tech, in Leesburg, performed a retrospective review of medical records collected from 3 EHM outbreaks in which this novel treatment combination was used. Megan Marchitello, DVM, a resident at the Marion duPont Scott Equine Medicine Center, described the case findings at the B y

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AAEP 65th Annual Convention in Denver. The first outbreak occurred on a small residential farm that held 4 horses; 2 of the horses had a recent history of travel and 1 had been recently introduced without a quarantine period. The second farm held 41 horses with no history of travel, but the horses had multiple shared water sources. The third facility held 66 horses with a much higher incidence of travel than the other 2 farms, and had recently held a horse show on the premises. â&#x20AC;&#x153;All 3 outbreaks occurred in a 6 month period between 2017 and 2018, and veterinarians from the Marion duPont Scott Equine Medical Center, 6 ambulatory

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practices and the Virginia Department of Agriculture and Consumer Services (VDACS), worked together to create a uniform quarantine and treatment protocol,” Dr. Marchitello said. The horses were considered positive for equine herpesvirus-1 (EHV-1) if they had a positive PCR test result or developed acute neurologic deficits. During the outbreak period, horses were considered negative if they had a negative PCR, even if they developed a fever. A horse was considered exposed if it shared “airspace” or husbandry staff with a known infected horse. Nasal secretions and blood were collected from all horses at facility 1 and only symptomatic horses at facilities 2 and 3. The samples were submitted to the VDACS to for testing. The farms quarantined the horses for 21 days after the last fever, and daily temperature checks were recommended at least twice a day. Any horse with a fever of 101.5° F, nasal discharge, lymphedema or acute neurologic deficits, was isolated from the general population. A standard treatment protocol was recommended at all facilities. After EHV-1 infection was confirmed, prophylactic valacyclovir was recommended for all ex-

posed horses. “Metaphylactic” heparin was then recommended for all horses that displayed clinical signs of disease. Additional treatments were recommended by the supervising veterinarian on a case by case basis, including anti-inflammatories and anti-oxidants. All horses showing neurologic deficits were given corticosteroids, mostly dexamethasone. Among all 3 outbreaks, 111 horses with a mean age of 11 were exposed to the virus; 23 horses developed clinical signs leading to a morbidity rate of 20%, according to Dr. Marchitello. “Four horses exhibited recurrent fever, however, repeatedly tested negative on PCR. So for the purpose of this study, they were considered unaffected. However, they were isolated from the general population and did receive our treatment protocol,” she said. The sick horses displayed a variety of clinical signs, including fever, lymphedema and nasal discharge. Ten horses aged 5 to 22 were diagnosed with EHM after developing neurologic deficits, including ataxia (10 horses), asymmetric vestibular deficits (2) and encephalopathy (1). “Heparin was administered at the onset of fever or other clinical signs of EHV-1 and always in conjunc-

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INFECTIOUS DISEASES

tion with valacyclovir,” she said. “Seventeen horses with clinical disease received heparin metaphyactically, 2 at the onset of neurologic disease and 15 at the onset of fever. Of these 15 horses, 4 went on to develop EHM.” Only 4 horses with clinical signs of EHM did not receive heparin and were euthanized for the development of 5/5 ataxia. “When evaluating the population of horses that developed clinical signs, targeted treatment was significantly associated with a decreased incidence of EHM. The 4 horses that did not receive our targeted treatment did receive other treatments like anti-inflammatories and antioxidants. However, they did not receive valacyclovir and heparin, and they failed to survive,” Dr. Marchitello said. “So overall, the take-home message is that all horses that received valacyclovir and heparin survived and all horses that did not receive this targeted treatment were euthanized,” she said. Understanding how EHV-1 infection occurs can help explain how this combination could be effective for infected horses, according to Dr. Marchitello. The virus enters the respiratory tract, infects the lymph nodes and then moves to the bloodstream. In the case of EHM, the virus can then disseminate to the lining of the blood vessels of the central nervous system, causing damage to the spinal cord or brain.

Heparin blocks thrombin production, which can decrease the viral load; valacyclovir decreases viremia and nasal shedding, she explained. The study had several limitations, Dr. Marchitello admitted. “Because of the retrospective nature of this study, our referral hospital was introduced to these outbreaks at different times of infection. And it was also difficult to enforce a standard treatment protocol due to varying client compliance,” she said. In addition, financial constraints limited the number of horses that were tested, so they did not know the true prevalence of infection. “Lastly, our reliance on qualitative rather than quantitative PCR may have decreased our sensitivity in detecting EHV, especially in the horses that experienced fevers and may have been low shedders,” she said. She said a case-control study is needed to evaluate this treatment plan, as well as other therapeutics that could block viral fusion or endocytosis. These studies would be worthwhile, because EHV-1 is one of the most prevalent infections among U.S. horses. Equine herpesvirus is ubiquitous in horse populations with prevalence ranging from 60% to 80%. “So, for practical purposes, the veterinarian should presume that most horses are latently infected,” Dr. Marchitello said. MeV

New Treatment May Prevent Overprescribing of Antibiotics Researchers at Texas A&M University and the University of Georgia found that gallium maltolate (GaM), a semimetal compound with antimicrobial and anti-inflammatory properties, could be a viable alternative to overprescribed antibiotics for Rhodococcus equi pneumonia. Current methods to screen for R. equi are imprecise and many foals are given prophylactic antibiotics, such as the combination of a macrolide with rifampin (MaR), even though they would not have developed pneumonia. For the study, the team screened 57 foals from 4 farms in central Kentucky for subclinical pneumonia, then divided the foals into 3 equal groups. Two groups contained foals with subclinical pneumonia, meaning ultrasounds found lesions on their lungs but the foals had no clinical signs. The foals also all lived on farms with positive cases of R. equi pneumonia that year. Those groups were given either MaR or GaM for 2 weeks. The third group served as a control group and was made up of similar aged, healthy foals, which were monitored and not given any treatment. After 2 weeks, researchers analyzed fecal samples from each foal. DNA tests revealed that the MaR treated group had an increase in both the number and diver12

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sity of antibiotic-resistant genes in the bacteria. Most alarming was the discovery that the bacteria were resistant to multiple drugs and antibiotics. The GaM-treated and control groups showed no change in the number or diversity of resistance genes, a positive finding. The team also experimentally infected soil plots with resistant and nonresistant strains of R. equi to see how foals might contaminate their environment with their excrement that can contain unabsorbed and metabolized antibiotics. MaR tended to reduce the number of bacteria in a plot's soil but increase the proportion that were resistant. MeV The research was funded by Morris Animal Foundation.

For more information: Alvarex-Narvaez S, Berghause LI, Morris ERA, et al. A common practice of widespread antimicrobial use in horse production promotes multi-drug resistance. Scientific Reports. 2020 Jan 22 [epublished]. https://www.nature.com/articles/s41598-020-57479-9

CARDIOLOGY

Smarter Smart Phone: Stall-side ECG A smartphone app that measures electrical activity in the heart is accurate enough to provide stall-side screening for arrhythmias, researchers have found. Previous studies have supported the utility of smartphone electrocardiograms (SpECG) for detecting rhythm and heart rate in horses. The new work, from a group at CEU Cardenal Herrera University in Valencia, Spain, shows that the apps appeared to be as effective as conventional ECGs at identifying atrial fibrillation and other anomalies—provided users take measurements from both sides of an animal’s thorax. “Electrocardiography has been mostly reserved for referral centers, and for most clinicians the costs and the training required to interpret ECGs has prevented a wider use in the general equine population. Now, every equine vet has the possibility to have an ECG in their pocket at a very affordable cost,” said Ignacio Corradini, MV, MSc, DipECEIM, who led the study. The app takes about 5 minutes to use and requires little training. “Another exciting thing for veterinarians is that the ECG could be included in regular health checks or even prepurchase examinations,” Dr. Corradini added. “We believe that this opens the door for earlier detection, increasing the chances of successful outcomes in the treatment of equine arrhythmias in the near future.” For their study, Dr. Corradini and his colleagues tested an SpECG app (AliveCor Veterinary Heart Monitor AC-002) on 50 horses ranging in age from 1 month to 31 years. As the investigators noted, the electrical sensors designed for mobile phones cannot be separated, as they can with conventional ECGs, so to compensate they took measurements on both sides of the animals’ thoraxes. They also compared the readings with those from a traditional ECG. Of the 50 horses, 15 were found to have a spontaneous arrhythmia on traditional ECG, including atrial fibrillation, sinus pause and atrioventricular block. The

Image courtesy of Dr. Ignacio Corradini

By Adam Marcus

A Smartphone app appears to be as effective as conventional ECGs at identifying atrial fibrillation.

SpECG detected all of those, they reported, although in one case, the anomaly appeared only when the app was used on the right side of the thorax. To use the app optimally, veterinarians should take 1-minute measurements from each side of the thorax, according to Dr. Corradini. “That’s because according to our study, recording an ECG from the right side provided additional information that was useful to help pick-up and characterize arrhythmias,” he said. Dr. Corradini said that, for the moment, the app is appropriate only as a screening tool. “The smartphone ECG is a good screening method, meaning that once an arrhythmia is picked up, the tracings should be sent to a specialist for evaluation,” Dr. Corradini told Modern Equine Vet. “If the arrhythmia is believed to be clinically important, it will most likely require the use of specialized equipment to make a definitive diagnosis. For the time being, no specific antiarrhythmic treatments should be attempted based solely on the information obtained by a smartphone ECG.” MeV

For more information: Corradini I, Fernandez-Ruiz A, Barba M, et al. Stall-side screening potential of a smartphone electrocardiogram recorded over both sides of the thorax in horses. JAVMA. 2020 April 28 [Epub ahead of print] https://onlinelibrary.wiley.com/doi/epdf/10.1111/jvim.15795 Kraus MS, Rishniw M, Divers TJ, et al. Utility and accuracy of a smartphone-based electrocardiogram device as compared to a standard base-apex electrocardiogram in the horse. Res Vet Sci. 2019;125:141-147. doi: 10.1016/j.rvsc.2019.05.018. Epub 2019 Jun DOI: 10.1016/j.rvsc.2019.05.018 https://pubmed.ncbi.nlm.nih.gov/31228737/#:~:text=Conclusions%3A%20The%20smartphone%2Dacquired%20 ECG,ECGs%2C%20resulting%20in%20a%20misdiagnosis. ModernEquineVet.com | Issue 7/2020

The Modern Equine Vet - July 2020

Articles inside

Valacyclovir and Heparin May Improve Survival in Horses with EHM

ASK THE NUTRITIONIST

MORE THAN A HITCHING POST

Smarter Smart Phone: Stall-side ECG

Antibiotic Alternative for R. Equi Prophylaxis

NEWS NOTES