The Modern Equine Vet - March 2022

The Modern

Equine Vet www.modernequinevet.com

5 Ways Ultrasonography Improves Foal Care

Identifying Horses with S. equi Hendra Virus Variant Identified Technician Update: Unresponsive Tachycardia Evaluating Your Practice's Value

Vol 12 Issue 3 2022

TABLE OF CONTENTS

COVER STORY

4 5 Ways Ultrasonography Improves Foal Care

Cover: Shutterstock/Alberto Duran Photography

INFECTIOUS DISEASE

Simple, Serial Lavage Helps ID Horses Carrying S. equi .......................10 Cellular Receptors Identified for EEE ............................................................12 Discovery of New Hendra Virus Variant in Horses ...................................25 CARDIOLOGY

AFib Rate Could Offer Non-Invasive Predictor of Recurrent Arrythmia ..................................................................14 TECHNICIAN UPDATE

Unresponsive Tachycardia in an Equine Patient During Surgical Correction of a Small Intestinal Volvulus...........................................16 NEWS NOTES

AAEP Issues Equine Piroplasmosis Guidelines........................................................................3 USTA Microchips More Than 40,000 Standardbreds..........................................................21 Variation Seen in People Assessing Equine Pain.................................................................21 BUSINESS PRACTICE

Now, Later, or Never: Evaluating Your Practice for Sale or Other Options...........................22 ADVERTISERS EpicurPharma.......................................................................................................3 CareCredit..............................................................................................................7 Merck Animal Health..........................................................................................9 Arenus Animal Health/Assure Gold...............................................................11

American Regent/Adequan.............................................................................13 Arenus Animal Health/Aleira..........................................................................15 Arenus Animal Health/Assure Gold...............................................................17 Arenus Animal Health/Releira........................................................................23

The Modern

Equine Vet SALES: Matthew Todd • Matthew Gerald EDITOR: Marie Rosenthal ART DIRECTOR: Jennifer Barlow CONTRIBUTING WRITERS: Paul Basilio • Adam Marcus Cath Paulhamus COPY EDITOR: Patty Wall Published by PO Box 935 • Morrisville, PA 19067 Marie Rosenthal and Jennifer Barlow, Publishers PERCYBO media  publishing

2

Issue 3/2022 | ModernEquineVet.com

LEGAL DISCLAIMER: The content in this digital issue is for general informational purposes only. PercyBo Publishing Media LLC makes no representations or warranties of any kind about the completeness, accuracy, timeliness, reliability or suitability of any of the information, including content or advertisements, contained in any of its digital content and expressly disclaims liability of any errors or omissions that may be presented within its content. PercyBo Publishing Media LLC reserves the right to alter or correct any content without any obligations. Furthermore, PercyBo disclaims any and all liability for any direct, indirect, or other damages arising from the use or misuse of the information presented in its digital content. The views expressed in its digital content are those of sources and authors and do not necessarily reflect the opinion or policy of PercyBo. The content is for veterinary professionals. ALL RIGHTS RESERVED. Reproduction in whole or in part without permission is prohibited.

NEWS NOTES

AAEP Issues Equine Piroplasmosis Guidelines Comprehensive guidelines to assist veterinarians with identification, control and prevention of equine piroplasmosis (EP), a bloodborne protozoal infection of equids with a mortality rate for infected horses of up to 50%, are now available on the AAEP’s website.

While natural tick-borne transmission of EP in the United States is rare, cases have been recognized in recent years specifically involving iatrogenic transmission in Quarter Horse racehorses. Guidelines author Angela Pelzel-McCluskey, DVM, MS, national epidemiologist for equine diseases at USDA APHIS Veterinary Services, said most of these racehorses had direct ties to unsanctioned racing and unhygienic practices by their owners and trainers.

“Re-use of needles, syringes and IV sets, blood-contamination of multidose drug vials, use of illegal blood products from other countries, and direct blood doping between horses have been identified as common methods of bloodborne disease transmission in this population,” Dr. Pelzel-McCluskey said. “Equine practitioners should be aware of the risk for EP and other bloodborne diseases, such as EIA [equine infectious anemia], in this

high-risk population and provide educational outreach to clients on appropriate biosecurity to prevent disease transmission among horses.”

It is recommended that current Quarter Horse racehorses be routinely tested for EP and EIA during their racing career. Equine practitioners encountering former Quarter Horse racehorses as part of a pre-purchase or routine exam should discuss with owners the risk of previous disease exposure and recommend testing.

EP is considered a foreign-animal disease in the United States. Any detection must be reported to the state veterinarian and/or to USDA APHIS Veterinary Services. Horses infected with EP can be enrolled in a USDA APHIS-approved EP treatment program, which is often successful at permanently eliminating the infection.

The EP guidelines were reviewed and approved by the AAEP’s Infectious Disease Committee and board of directors.

MeV

FOR MORE INFORMATION,

https://aaep.org/document/aaep-infectious-diseaseguidelines-equine-piroplasmosis.

FDA Registered Facility

AVAILABLE FOR OFFICE USE

GUAIFENESIN 50 mg/mL, 1000 mL Bag

INJECTION SOLUTION

TAC OINTMENT 0.03% and 1% (Tacrolimus Ophthalmic)

•

Made under cGMP1; same FDA regulations followed by the pharmaceutical manufacturing industry

•

CONSISTENT QUALITY backed by the FDA manufacturing process 1 cGMP - Current Good Manufacturing Practices

Order Today!

888-508-5032

IMAGING

4

Issue 3/2022 | ModernEquineVet.com

B y

M a r i e

R o s e n

t

h

a

,

M S

WAYS

l

Ultrasonography IMPROVES FOAL CARE

Anyone who manages foals

understands the challenges of treating these young horses whose health can be precarious. A foal that looks fine can be “extremely sick within minutes to hours,” explained William F. Gilsenan, VMD, DACVIM (LAIM), an internal medicine specialist at Rood and Riddle Equine Hospital.

“This poses ambulatory veterinarians with a unique challenge where the situation may be dynamic, the patient might be quite ill, and information that you'd like to have diagnostically—like laboratory work—isn't readily available,” he said.

Portable ultrasonography can

be a useful diagnostic tool in these situations, according to Dr. Gilsenan.

“If you own a portable ultrasonographic machine, and if you treat foals and you're not using this regularly, I think you are missing out on an extremely helpful diagnostic tool,” he said.

The biggest drawback for many veterinarians is that they are uncomfortable with interpreting the image. However, there are so many advantages that it is a tool that is worth mastering, according to Dr. Gilsenan.

“The more you use it, the more you're going to be comfortable with it,” he said. Just like with physical examination done by practitioners, repetition of ultrasound examinations is going to enhance their skill and help them to discern between normal and abnormal.

“And as such, it should be employed as often as you can, if nothing else to give you the comfort level that's going to allow you to really use that information, to interpret it and help you guide treatment decisions and diagnostic decisions going forward,” said Dr. Gilsenan, who offered some tips for using the ultrasound equipment in foals at the 67th AAEP Annual Convention & Trade Show held in Tennessee.

Ultrasonography is not a one-person job. Someone must restrain the foal. He suggested the person who is restraining the foal put his or her hand over the shoulder ModernEquineVet.com | Issue 3/2022

5

Shutterstock/Osetrik

Ultrasonography Handy Tool for Managing Foals

IMAGING

Evaluation of the Thorax

The pleural line seen on ultrasound of the thorax.

Image courtesy of Gilsenan W, AAEP Proceedings 2021 Vol. 67

6

of the foal, instead of the throat area, which will minimize stress and movement, and decrease the amount of chemical restraint that will be needed.

His preference for chemical restraint of foals that are younger than 2 weeks is diazepam by itself, or with butorphanol and xylazine for older foals.

Try to perform the ultrasound in a quiet, dimly lit environment. This allows the veterinarian to focus and see the screen better and the foal will be less stressed.

“We're going to want to get this examination done as rapidly as possible and the dim light is going to allow you to look at the screen as best as you can, and to interpret the image that you're getting from the ultrasound as rapidly as possible,” he said.

There are advantages and disadvantages to each probe. A large-curve linear probe will generate signals to the lowest frequency, meaning it will penetrate quite deeply. Although that could be an advantage for certain structures, it compromises details.

A micro convex or small-curved linear probe will generate signals at a higher frequency, which enhances detail.

A rectal probe also will generate signals at a much higher frequency than the large-curve linear probe, which will give better detail, but will not penetrate that deeply. A rectal probe can be useful when looking at certain structures, however, such as a neonatal rib when a fracture is suspected.

Using the correct conductive medium, either isopropyl alcohol or ultrasound coupling gel, is critical.

Dr. Gilsenan prefers isopropyl alcohol because it's readily available, dries rapidly and requires less cleanup.

He recommends that veterinarians develop a routine and always perform the ultrasonography in the same order, so nothing is missed. “There's no order that's right.

It's just to help you figure out what works for you and helps you anticipate what to see and ensures that you don't miss any structures,” Dr. Gilsenan explained.

Issue 3/2022 | ModernEquineVet.com

For instance, when evaluating the thorax, Dr. Gilsenan takes a dorsal-to-ventral direction from the intercostal spaces in the dorsum until he can visualize the diaphragm or abdominal viscera. Then he moves caudally to cranially to the lung, which usually occurs before the 17th intercostal space.

Common ultrasonographic findings of the lung include: • Comet-tail artifacts, which represent irregularities on the pleural surface that indicate that some disease is present, but the lung is still receiving air.

• Pulmonary consolidation is another abnormality that can occur when the lung is not aerated. The consolidation appears isoechoic with the liver, which means it produces an echo similar to surrounding structures. This so-called "hepatization of the lung" makes the lung difficult to isolate, It is often a sign of pneumonia, possibly bacterial.

“You can distinguish this from the liver because you can see some parts of the lung that are aerated through which the ultrasound signal is not passing through,” Dr. Gilsenan explained.

• A lung with a pulmonary abscess tends to be well aerated.

• Plural effusion is another common ultrasonographic finding on the thoracic exam in foals.

When plural effusion is present, you can often see the diaphragm or liver, which are not present when the lung is well aerated. “And that's because there is some sort of liquid or effusion in the plural space,” Dr. Gilsenan explained.

To find out what is causing the effusion, the ultrasound would typically be followed up with a thoracocentesis.

Evaluating the Abdomen

When evaluating the abdomen, Dr. Gilsenan looks at the left flank, then the right flank. He prefers to start his examination in the caudal abdomen, starting at the caudal aspect of the paralumbar fossa and working dorsally to ventrally along the paralumbar fossa until he reaches the ribs. At that point, he works on each intercostal space ventrally to the thoracic cavity, then cranially until the elbow, to finish the exam.

On the left flank of the abdomen, a veterinarian will see the spleen, left kidney, stomach, large colon and liver. The size of the stomach will vary depending on the amount the foal has ingested.

“Ultrasonographic evaluation of the stomach is an extremely important part of the foal abdominal ultrasonic examination, especially in foals that are showing signs of colic,” Dr. Gilsenan said. A thick-

Wherever you’re working, we work to keep you at the heart of care.

CareCredit has always provided clients a flexible, budget-friendly way to pay over time.* But your job is unique. So we developed a contactless, all-digital financing experience to support all the ways (and places) you provide care, and it’s customized for your practice. Clients can learn, see if they prequalify, apply and pay* with the CareCredit credit card, anytime from anywhere on their smart device. And you get paid in just two business days.

It’s a payment solution as versatile and flexible as you. To learn more, visit carecredit.com/mycustomlink.

Experience how it works. Simply scan the QR code with your mobile phone.

Get started today for free. Mention code MES2022VA when you call to enroll and receive a $30 Amazon® gift card.** 844-812-8111.

Offer valid through 05/31/2022.

*Subject to credit approval. **Offer expires 05/31/2022. Offer valid for one (1) $30 Amazon.com Gift Card per practice while supplies last. Offer is non-transferable. For newly enrolled providers only. Please allow 6-8 weeks for delivery. Restrictions apply, see amazon.com/gc-legal. Use of the Amazon name does not imply partnership, endorsement or sponsorship.

©2022 Synchrony Bank MES2022VA

IMAGING

HOW DOES ULTRASONOGRAPHY WORK? Diagnostic ultrasonography is a non-invasive diagnostic technique used to image soft tissue inside the body. Ultrasound probes, called transducers, produce sound waves that echo off tissues and are returned to the transducer. When these echoes hit the transducer, they generate electrical signals that are sent to the ultrasound scanner, which displays an image. The sound waves are reflected back to the transducer by boundaries between tissues in the path of the beam, such as the boundary between fluid and soft tissue or tissue and bone. Areas that appear dark or black mean that the waves go through them without emitting a return echo.

Image courtesy of Gilsenan W, AAEP Proceedings 2021 Vol. 67

ened, turgid stomach wall, or a stomach that is abnormally enlarged are important signs.

He showed an ultrasound where the stomach was markedly round and could be imaged all the way to the 14th intercostal space. To him, this suggested that something was impeding gastric flow, such as a mechanical obstruction or a functional obstruction like ileus, indicating the need to pass a gastric tube “because the foal is certainly going to be at risk of gastric rupture,” he explained.

On the right flank, one can see the right side of the abdomen, the right kidney, the duodenum, the liver and the large colon. When he evaluates the right flank, again, he starts caudally in the paralumbar fossa and works his way in increasingly cranial planes until he reaches the ribs, then he works ventrally to the lung fields. He evaluates every part of the abdominal cavity until the elbow.

“Ultrasonographic evaluation of the duodenum is another extremely important component of the abdominal ultrasound exam in the foal,” he said.

“When you're looking at the duodenum, you want to look at wall thickness. So again, this is the duodenal wall—and for a foal—normal wall thickness is about 2 or 3 millimeters,” he said.

If it’s turgid or distended, that will signal a problem, possibly an obstruction.

“There's no hard sciences about how distended is ‘too distended,’ to signal a surgical intervention,” heexplained, so serial images might be useful.

“Personally, if I see an internal diameter in a young foal greater than 2 or 3 centimeters, I get very concerned about the potential for a mechanical obstruction, but even with the severe functional obstruction like ileus, you may see some pretty marked distention of the duodenum,” he said.

Evaluation of the Ventrum

One typically will see the ventrum, large colon, the bladder, the internal umbilical remnant, the small intestine and peritoneal effusion. Dr. Gilsenan prefers to start in the most medial plane cranially and then work his way caudally and into progressively 8

Issue 3/2022 | ModernEquineVet.com

lateral planes working outward toward the flanks.

It’s helpful to look at colonic ingestions. A normal large colon will show shadowing that indicates gaseous and solid feed ingest that probably has some liquid in it. If the foal has colitis or diarrhea, the image will likely have no gas or solid feed, and instead be filled with liquid and echogenic material.

The small intestines are a little tricky to visualize because they can be anywhere in the abdominal cavity. Even in the normal foal there may be "a certain amount gas or solid feed in the large colon. If a foal is colicky, fluid-filled small intestinal loops tend to sink eventually. They are often quite turgidly distended, and the walls tend to be thick. Normal wall thickness in a small intestine should be less than 3 mm in a foal.

Evaluation of the Internal Umbilicus

Evaluation of the internal umbilical remnant should be performed in any foal with fever of unknown origin. It should be performed on farms, or if the horse has a history of an internal umbilical remnant.

“It's extremely important to remember that the presence of a normal, external umbilical remnant does not preclude the presence of severe internal remnant infection,” he said.

When evaluating the internal remnant, Dr. Gilsenan typically identifies the stalk--the external umbilical remnant--and then uses the ultrasound probe to come up from it caudally and then looks cleanly onto the internal remnant itself, and then moves in a transverse plane, fanning caudally.

By the time the foal is about 5 or 6 weeks of age, the internal remnant should mostly be gone. In a newborn, the internal remnant can be up to 2.5 cm in diameter. The diameter of each umbilical artery should be less than 1 cm, and the umbilical vein should be less than 7 mm. Larger remnants may be an indication for antimicrobial therapy.

As the saying goes, practice makes perfect, and the more the ultrasonography is used during a foal examination, the more it can improve one’s diagnosis. MeV

There’s a Fine Line in Influenza Protection Only PRESTIGE® Contains Florida ‘13 PRESTIGE® flu-containing vaccines deliver advanced influenza protection against the most relevant flu strains circulating today, meeting OIE and AAEP guidelines for Clade 1 & Clade 2 protection.

1

Data on file. Merck Animal Health.

Copyright © 2022 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved.

US-PRT-210800001

Discovered through the Equine Respiratory Biosurveillance Program Proven relevant through Genetic Sequencing1 From the Influenza Innovators at Merck Animal Health Talk to your Merck Animal Health representative today to learn more about the PRESTIGE® line of influenza vaccines or visit PrestigeVaccines.com

INFECTIOUS DISEASES

Simple, Serial Lavage Helps ID Horses Carrying S. equi

By Adam Marcus Identifying horses at risk for spreading strangles may have gotten significantly more efficient, thanks to research from Sweden that shows that repeated negative samples of wash from the animals’ nasal passages almost always indicates they no longer carry harmful microbes.

“Before this publication it was reported that carrier state detection required expensive and invasive use of an endoscope and sampling from the guttural pouches for Streptococcus equi,” John Pringle, DVM, PhD, a professor emeritus at the Swedish University of Agricultural Sciences, in Uppsala, and the lead author of the study, told Modern Equine Vet. “This work showed that a far simpler, and easily repeated use of sampling from the nasopharynx may be used to show carrier-free status.”

Dr. Pringle and his colleagues stressed that the findings came from horses involved in a single outbreak of strangles, and they require validation.

Although S. equi generally is not fatal to horses and responds well to treatment, outbreaks carry substantial morbidity for horses and headaches for stables. Moreover, S. equi often lies effectively dormant in the upper respiratory tract of previously infected animals, who become symptomless carriers of the germs.

As a result, stables generally isolate horses known to have been infected with S. equi for many weeks following clinical recovery. Yet, a proportion of the horses will carry the bacteria far longer after the isolation period.

Although the American College of Veterinary Internal Medicine recommends testing previously infected horses to see if they’re carriers of S. equi, the society is split about how best to do so. A 2005 consensus statement advised using PCR testing from nasopharyngeal swabs or lavage—3 clean weeks in

a row is considered a passing grade. However, more recent guidance said a single, endoscopically guided guttural pouch lavage (GPL) was a superior method of surveillance.

“Unfortunately, neither of these publications provided evidence-based studies to support the statements. Although clearly important in carrier detection, GPL is more invasive and costly. Also, use of an endoscope can result in false positives,” the authors of the new study noted.

For the prospective, observational analysis, Dr. Pringle’s group tracked 41 Icelandic riding horses struck by an outbreak of strangles associated with S. equi. All of the animals had developed symptoms of the infection and all recovered.

Starting at 18 weeks after the index case of infection, the researchers took regular samples of nasopharyngeal lavage fluid, ending sampling 27 weeks later with sampling of both nasopharyngeal and guttural pouches by lavage.

According to the researchers, of the 24 horses that tested negative for S. equi at week 45 of the study, only 4 also tested negative on each of 3 consecutive weekly lavages taken between weeks 28 and 30. However, 10 of the 11 horses with at least 3 negative lavage tests taken at weeks 18, 28, 29, and 30 remained free of the microbes at week 45 (P=0.03), they reported.

Dr. Pringle noted that “a very important finding was that sampling from the guttural pouch, on a single occasion, can be falsely negative for true carriers of S. equi and should not be relied upon to determine carrier status.”

A pressing question, Dr. Pringle added, is how infectious these “silent carriers” are. “We are currently examining this with experimental exposure studies—that await our analyses—which will be vital to put more pieces into the puzzle of managing of strangles,” he said.

MeV

Outbreaks of Streptococcus equi carry substantial morbidity for horses and headaches for owners.

For more information: Pringle J, Aspán A, Riihimäki M. Repeated nasopharyngeal lavage predicts freedom from silent carriage of Streptococcus equi after a strangles outbreak J Vet Intern Med. 2022;1–5 2022 Jan. 24. https://doi.org/10.1111/jvim.16368 https://onlinelibrary.wiley.com/doi/10.1111/jvim.16368 10

Issue 3/2022 | ModernEquineVet.com

SO INNOVATIVE...

IT’S LIKE MAGIC

Assure Guard Gold ®

AND

The Ultimate Digestive Aid

®

THE REAL MAGIC IS IN THE RESULTS Together, Assure Guard Gold-NG And Assure Guard Gold Create A Powerhouse Against Your Most Challenging Digestive Cases.

Use Assure Guard Gold-NG For Fast Relief And Maintain Excellent Digestive Health With Assure Guard Gold.

Replace your mineral oil, electrolytes, adsorbents, or other treatment options with Assure Guard Gold-NG the only effective and easy to administer slow gelling quick relief formulation including 2 cups of ultra pure psyllium, 72 billion CFU of probiotics, prebiotics, antacids, L-glutamine, electrolytes and energy.

For continued support, consider a 10 day supply of Assure Guard Gold after treatment.

Ask your Arenus Veterinary Solution Specialist how Assure Guard Gold-NG and Assure Guard Gold can help your equine patients quickly and effectively recover from the digestive upsets you treat daily.

Arenus Animal Health | 866-791-3344 | www.arenus.com

INFECTIOUS DISEASES

Under a magnification of 83,900X, this digitally colorized transmission electron microscopic (TEM) image depicts a salivary gland tissue section that had been extracted from a mosquito, which was infected by the eastern equine encephalitis (EEE) virus. The viral particles have been colorized red. Image

by Fred Murphy; Sylvia Whitfield/ CDC.

Cellular Receptors Identified for EEE Harvard Medical School researchers identified a set of cellular receptors for at least 3 related alphaviruses shared across mosquitoes, animals and people. This information could lead to better diagnosis and treatment.

The researchers tested a decoy molecule that successfully prevented infection and slowed disease progression in a series of experiments in cells and animal models— an important first step toward developing preventive and curative medicines against these highly pathogenic virus' with pandemic potential.

Understanding the basic biology of a virus's life cycle is crucial to finding a way to prevent an illness, senior author Jonathan Abraham, MD, MPH, assistant professor of microbiology in the Blavatnik Institute at Harvard and an infectious disease specialist at Brigham and Women's Hospital.

“Understanding how a virus enters and infects a cell is as basic as it gets,” he said, adding that viral entry marks the beginning of infection, making it a good place to look for preventive strategies and treatments.

The alphaviruses the researchers studied, including eastern equine encephalitis (EEE), have a history of causing deadly, if short-lived, outbreaks, but little is known about how the virus attacks host cells. Only a few other receptors related to infection from alphaviruses have been identified, which limits treatment options.

Infected mosquitoes

EEE, western equine encephalitis (WEE) and Venezuelan equine encephalitis (VEE) are caused by alphaviruses. Birds and rodents are the primary reservoirs, but unvaccinated horses are particularly susceptible and often serve as sentinels. Since these diseases are zoonotic, they are a public health concern. EEE is the most common of the 3 and is found widely in several regions of the United States, especially where there are high mosquito populations, according to the Department of Agriculture.

New screening tools and techniques in molecular biology, protein biochemistry, biophysics and structural biology provide unprecedented power to learn more than ever about the basic biology of viruses before they emerge as global threats, Dr. Abraham said.

“The time to prepare for these uncertain but potentially catastrophic scenarios is not when they occur, but well before they do,” "he explained.

For the current study, the researchers first used a CRISPR-Cas9 gene-editing screen to identify a receptor for Semliki Forest virus (SFV) on human cells. SFV is an alphavirus that can cause severe neurologic disease and death in rodents and other animals.

The receptors that the researchers found for SFV were also compatible with EEE and another related virus called Sindbis, which can cause fever and severe joint pain in humans and causes neurological disease in animals and rodents “That's why it's important to study these viruses as families,” Dr. Abraham said. “You can end up studying a virus like SFV and discover something really exciting about the biology of related viruses that has the potential to unlock novel ways to treat new categories of viruses that are capable of causing serious disease and outbreaks.”

Identifying a receptor for multiple viruses would give the scientists, physicians and veterinarians a running start on developing tools to prevent, control and treat infections should an outbreak of one of the viruses occur, Dr. Abraham said.

As a means of verifying that the receptors in question were important in causing infection, the researchers conducted experiments with a decoy protein, a molecule with a structure that mimics the receptor and can trick the virus into binding to the drug instead of to the host cell it aims to infect. The molecule, in effect, disables the virus and averts entry into the host cell, preventing infection.

The team's experiments demonstrated that blocking the virus from interacting with the host cell receptor prevented infection of human and mouse neurons. They also found that the decoy molecule protected infected mice from developing rapidly fatal alphavirus encephalitis—a finding that the researchers said suggests this pathway could be targeted by drugs or antibodies to treat alphavirus encephalitis.

This research was supported by the U.S. Department of Health & Human Services, the National Institutes of Health, the Burroughs Wellcome Fund, the William Randolph Hearst Foundation, the Brigham and Women's Hospital Harvard Milton Fund , the Vallee Scholar Award, and the Howard Hughes Medical Institute.

MeV

For more information: Clark LE, Clark SA, Lin CY, et al. VLDLR and ApoER2 are receptors for multiple alphaviruses. Nature. 2021;602:475-480. https://www.nature.com/articles/s41586-021-04326-0

12

Issue 3/2022 | ModernEquineVet.com

There’s nothing else like it.

For more than 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 over a 2, 4, 5 lifetime. Discover if Adequan is the right choice. Visit adequan.com/Ordering-Information to find a distributor and place an order today.

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 1-888-354-4857 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. © 2021, American Regent, Inc. PP-AI-US-0629 05/2021

CARDIOLOGY

AFib Rate Could Offer Non-Invasive Predictor of Recurrent Arrythmia

By Adam Marcus convert to sinus rhythm, and these Noninvasive cardiac testing can horses had higher AFR than did accurately predict which horses the horses that responded successare likely to experience relapses of fully to the drug (383 vs. 351 fpm; atrial fibrillation (AFib) after treatP<0.01), according to the researchment for the arrhythmia, researchers. All but 1 horse that underwent ers found.

TVEC successfully achieved norAs with humans, AFib is prevamal sinus rhythm. lent in equids—particularly larger Over the next 6 months, 12% of breeds—affecting as many as 2.5% horses given quinidine, and 34% of of animals, depending on the those that received TVEC, experibreed, and can significantly imenced recurrent atrial fibrillation. pair exercise tolerance. Although Although AFR did not appear to —Dr. Rikke Buhl (above) treatment with drugs and devices predict risk of recurrence in horses can correct the abnormal heart treated with quinidine, the marker rhythm, relapse is common, ocwas strongly associated with relapse curring in as many as about 40% of cases. Predicting in the animals that underwent TVEC, the researchers rewhich animals are most at risk of relapse could help ported. In this group, an AFR above 380 fpm was linked clinicians better manage atrial fibrillation, according with a 2.4-fold greater likelihood of recurrence (95% to Rikke Buhl, DVM, PhD, a professor in the Departconfidence interval 1.2–4.8; P=0.01), they found. ment of Veterinary Clinical Sciences at the University “Horses with high AFR had a higher risk of getof Copenhagen, in Denmark, and the first author of the ting AF again after a successful cardioversion to new study. sinus rhythm,” Dr. Buhl told Modern Equine Vet. One method for predicting relapse that has gained “Therefore, it seems that high AFR had a poor progrecent attention is the atrial fibrillation rate (AFR), nosis for keeping the heart in normal sinus rhythm. which is obtained by surface electrocardiography This can be helpful for the practicing vet as they can (ECG). AFR is thought to reflect electrical remodeling add this value to the other clinical parameters that in the heart. The higher rate of fibrillations per minassist in prognostication.” ute—expressed as the number of waves per minute The researchers noted that the TVEC group in(fpm)—the greater the remodeling. cluded more older, and especially Warmblood animals, For the new study, Dr. Buhl and her colleagues at which are known to be more prone to recurrent AFib institutions in the United States, Europe and Dubai and a higher prevalence of mitral regurgitation. “These sought to learn if AFR could be used to predict relapse factors may increase the complexity of AF and the atria of AFib in 195 horses. Of those, 74 received nasogasbecomes more remodeled. Whether this remodeling tric administration of the drug quinidine, a standard occurred before AF or as a consequence of AF is diftherapy for AFib, and 121 received an intervention ficult to answer,” Dr. Buhl said. called transvenous electrical cardioversion (TVEC), an At the moment, she added, ECG analysis occurs invasive procedure in which 2 catheters are introduced post-processing, but in the future the technology may through a vein in the neck and positioned in the heart, evolve to calculate AFR instantaneously. “That would and the organ is pulsed with electricity until normal siprovide the clinician with information that can assist nus rhythm returns. not only in treatment selection, but also for prognostiOf the animals treated with quinidine, 10 did not cation of the risk of AF recurrence,” she said.

MeV

AFib is prevalent in equids.

For more information: Buhl R, Hesselkilde EM, Carstensen H, et al. Atrial fibrillatory rate as predictor of recurrence of atrial fibrillation in horses treated medically or with electrical cardioversion. Equine Vet J. 2021 Dec. 27. https://doi.org/10.1111/evj.13551 https://beva.onlinelibrary.wiley.com/doi/10.1111/evj.13551 14

Issue 3/2022 | ModernEquineVet.com

IN A WORLD OF ITS OWN

Researched Respiratory Support Researched and Proven as an aid in controlling IAD and RAO Recommended in the ACVIM Consensus Statement on Respiratory Disease (1)

(2)

Not all Omega 3’s are the same; use the Researched and Recommended 1500mg Purified DHA formulation.

Your Clients Deserve The Best in a Non-Pharmaceutical Solution.

– Using the Best Matters References: [1] Nogradi N, Couetil LL, Messick J, Stochelski MA, Burgess JA. Evaluation of an Omega-3 Fatty Acid Containing Feed Supplement in the Management of Horses with Chronic Lower Airway Inflammatory Diseases. J Vet Intern Med 2015; 29:299-306.

[2] Couetil LL, Cardwell J.M, Gerber V, Lavoie J.-P, Leguillette R, Richard E.A. Inflammatory Airway Disease of Horses. ACVIM Consensus Statement J of Vet Intern Med 2016; 30:503-515 p. 508-510.

Check with Arenus on how Aleira can help your equine patients effectively cope with respiratory and immune function disorders. See how Aleira can help you to reduce or eliminate pharmaceutical interventions.

Arenus Animal Health | 866-791-3344 | www.arenus.com

TECHNICIAN UPDATE

Unresponsive Tachycardia in an Equine Patient During Surgical Correction of a Small Intestinal Volvulus

By Lori Dressel CVT, BSP, VTS (AVTAA) Lg Animal, and Jane Quandt DVM, MS, DACVAA, DACVECC 24-year-old, 340-kg gelding pony was admitted to the University of Georgia Veterinary Teaching Hospital for evaluation of small intestinal colic. According to the owner, the patient became lethargic and depressed for 12 hours before the referring veterinarian was called. The patient was referred because the pony was nonresponsive to treatment and had previous colic surgery, an exploratory celiotomy 3 years prior for a strangulating lipoma. At that time 8 feet of necrotic bowel were removed, and a jejunocecostomy was performed.

Clinical Examination

Clinical Findings

Over the next few days the patient seemed to gradually improve until the evening of the 5th night. The patient required several doses of IV xylazine and butorphanol due to uncontrollable pain with violent rolling. The patient underwent an exploratory celiotomy that evening. The surgical diagnosis was a distended small intestine and colon displacement. Biopsies were taken of the intestine and histopathologically diagnosed as lymphocytic plasmacytic enteritis with eosinophils.

Following surgery, the patient was maintained on IV fluids, IV lidocaine CRI, IV anti-inflammatories such as flunixin meglumine, oral gastrointestinal protectant omeprazole and sucralfate, IV dimethyl sulfoxide (DMSO), and IV antibiotics gentamicin sulfate and penicillin G potassium. There were intermittent bouts of tachycardia, fever, and tachypnea.

The patient was passing feces, and food was slowly being rein-

A 24-year-old gelding was lethargic and depressed for 12 hours before the referring veterinarian was called.

Images courtesy of Lori Dressel

Upon arrival at the teaching hospital, the patient was dull, lethargic and depressed. He had a body condition score of 5/9, heart rate of 40 bpm, respiration rate of 20 bpm, and a rectal temperature of 99.3° F. The mucus membranes were hyperemic and moist with a prolonged capillary refill time of 3 seconds. No abnormalities were heard on auscultation of the heart and lungs. Borborygmi were auscultated in all abdominal quadrants. The blood work showed a PCV of 22% and TS of 6.0 g/dL (range PCV 26–45%, TS 4.6-6.9 g/dL). Abnormal CBC findings

were a fibrinogen of 500 mg/dL (range 100-400), and lymphopenia of 1.118x10 ^3/µL (range 5.7-11.7x10 ^3/µL). There was no net reflux; the rectal exam was normal, and the abdominal ultrasonography results showed a thickened small intestine. The patient was placed on IV fluids and taken to a stall for observation.

The horse is sedated and awaiting transfer to the induction stall. While the sedation takes effect, the patient is cleaned and clipped, and his mouth is rinsed.

16

Issue 3/2022 | ModernEquineVet.com

The patient is in right lateral with his head extended. A bite block was placed in between the front teeth and a 26mm endotracheal tube was placed before the patient is hoisted and placed in the OR in dorsal recumbency.

ALL OTHERS

FALL SHORT.

Assure Guard Gold ®

The Ultimate Digestive Aid

®

The Trusted Solution of Equine Veterinary Professionals.

Researched and Patented for the treatment of Recurrent Colic, Chronic Diarrhea, Dysmotility and Ulcers.

Ask one of our Veterinary Solutions Specialists how Assure Guard Gold and the new Assure Advisor Mobile App can help you guide your patients to improve digestive health.

Arenus Animal Health | 866-791-3344 | www.arenus.com

TECHNICIAN UPDATE

TABLE 1 Results of an arterial blood gas performed in a pony that developed respiratory and metabolic acidosis with an elevated lactate.

BLOOD SAMPLES NO. Variables

1

2

3

4

pH

7.365

7.270

7.330

7.451

pC02 (mmHg)

37.0

45.4

35.5

29.1

p02 (mmHg)

44.0

364.8

317.4

90.6

HC03 (mmol/L)

21.4

21.0

19.3

20.5

BE(mmol/L)

–3.0

–5.3

–5.3

–2.3

Lactate (mEq/L)

4.4

4.9

4.1

3.3

iCa (mmol/L)

1.5

1.5

1.24

1.39

Glu (mg/dl)

263.0

221.0

187.0

205.0

Sample 1 was a venous sample collected the morning of anesthesia. Sample 2 was a baseline arterial sample collected shortly after the horse was hoisted and placed on inhalant. Sample 3 was an arterial sample collected 70 minutes after sample 2. Sample 4 was a venous sample collected 160 minutes after the anesthetic was discontinued.

troduced. The patient had a lymphopenia of 1.001x10 3̂ , and fibrinogen of 600 mg/dL. The pony seemed to be recovering until 7 days later, when over a 15-hour period, he became more painful.

The patient received several doses of IV xylazine, detomidine hydrochloride, and butorphanol for pain control. The patient produced 6 L of gastric reflux overnight, a nasogastric tube was placed, and fluids were increased to keep up with the fluid loss. Surgery was recommended, the patient was given 22,000 IU/ kg IV penicillin G potassium, 6.6 g/kg IV gentamicin sulfate, and 1.1 mg/kg IV flunixin meglumine preoperatively.

Clinical Procedure

At this point, the anesthesia technician was called in to manage the anesthesia for the surgical celiotomy. The author was in charge of the anesthesia and analgesia,

Once placed in dorsal recumbency, the patient is put on inhalant, oxygen and a ventilator. Also, all measuring parameters are placed and recorded every 5 mins.

18

Issue 3/2022 | ModernEquineVet.com

with an anesthesiologist available for consultation if needed. After a thorough exam and being brought upto-date on the case, an anesthetic plan was devised for the patient.

Pre-medication was 0.29 mg/kg IV xylazine and induction behind a swing door with 0.08 mg/kg diazepam and 1.73 mg/kg ketamine given IV. A 26 mm endotracheal tube was introduced to the trachea with the pony in lateral recumbency. The cuff was inflated to 20 cm H2O to prevent inhalant leaking from around the endotracheal tube. Anesthesia was maintained with isoflurane in 100% oxygen delivered at a concentration of 1% to 3%.

Monitoring consisted of ECG, inhalant gas analysis, capnography, pulse oximetry, direct blood pressure, blood gas analysis, body temperature, pulse rate, and respiratory rate. Blood pressure was monitored via an arterial catheter placed in the facial artery and measured with a pressure transducer. Intermittent positive pressure ventilation was initiated at 2 breaths per minute, 4 L tidal volume and a peak inspiratory pressure (PIP) of 20 cmH20. Plasma-Lyte, was administered at 10 mL/kg/hr IV and a baseline blood gas analysis was preformed.

The initial MAP was 55 mmHg and IV dobutamine was started at 2 µg/kg/min or to effect. The baseline blood gas revealed a mild metabolic and respiratory acidosis (Table 1) and an elevated lactate of 4.9 mmol/L. The mechanical ventilator rate was increased to 8 bpm with a tidal volume of 5 L and a PIP of 23 cmH20. It was observed that the patient’s blood pressure decreased during the inspiratory phase of ventilation.

Mechanical ventilation causes positive pressure in the thorax which decreases blood pressure due to decreased venous return. This hypotension will be exacerbated by hypovolemia. Once MAP was above 70 mmHg an IV lidocaine bolus of 1.3 mg/kg was given

Recovery was important, as the horse had spontaneous reflux. And endotracheal tube was taped in with two nasopharyngeal tubes placed in each nostril. Once standing, the endotracheal tube was removed, but the horse will still have an airway with the nasopharyngeal tubes.

Cardiac output is determined by stroke volume (SV) and heart rate (HR) (CO= HR x SV). The heart rate affects the cardiac output, CO, which affects blood pressure. In horses, the largest change in cardiac output is usually attributable to HR change. The normal resting heart rate of a horse is 24–40 bpm and 220–240 bpm in an exercising horse.

Inhalant anesthesia also causes changes in the cardiovascular system. The factors that affect the cardiovascular system during anesthesia are:

surgery. A lidocaine CRI was added to the protocol to improve analgesia, improve gastrointestinal motility, provide antiinflammatory effects and provide MAC-sparing effects.

As the procedure progressed and the HR continued to increase, isoflurane was discontinued, and sevoflurane was started. Although isoflurane and sevoflurane have similar cardiovascular effects, the change in inhalants was done to determine if this may have minimized the continued increase of the HR. No change in HR was subsequently observed.

• anesthetic drug doses, • changes of PaC02, • mechanical ventilation, • noxious stimulation/pain, • procedure duration, • drugs and inhalant used • vascular fluid volumes.

All of which can potentially affect an anesthetic episode in horses undergoing surgery for GI lesions. The horse in this report had a heart rate 50–55 bpm prior to surgery, which is considered tachycardic for the equine patient.

The anesthetic drug doses that this patient was given for pre-medication and induction were titrated to effect due to his compromised condition. The premedication given was xylazine which is an alpha-2 agonist. Xylazine, which produces excellent sedation and analgesia, can produce increased blood pressures, followed by decreases in BP, HR, CO, and second degree atroventricular block and ileus.

The inhalant anesthetic isoflurane was used. The vaporizer setting was kept at 1% to 3% and the end tidal gas never exceeded 1% at the beginning of

Oxygenation is impaired by respiratory-depressant drugs, recumbency and positioning in a normal patient. Gas exchange, whether it is oxygen or carbon dioxide, is even more compromised by the horse’s size and weight. When a compromised patient is placed in dorsal recumbency for a colic procedure, gas exchange is generally impaired. This is due to compression of the dependent lung lobes by the GI tract pushing on the diaphragm, causing the blood flow to the compressed lobes to be less oxygenated due to ventilation/perfusion mismatch.

Procedures lasting longer than 61 minutes have a decreased complication and death risk compared with those lasting longer than 241 minutes. The anesthesia time for this patient was 152 minutes, which may have increased risk.

The patient’s high heart rate was not a complication in any of the previous surgeries. The unresponsive tachycardia throughout this surgical procedure was hypothesized to be due to a sympathetic response caused by stomach distention that resolved by spontaneous gastric reflux and relief of gastric distention.

Gastric distention should be considered ruled out for tachycardia, in anesthetized patients with small intestinal disease, if no other cause of tachycardia is found.

over a 5-minute period and a CRI of 0.05 mg/kg/min was started.

The patient was given 0.02 mg/kg of butorphanol IV for analgesia. The patient’s HR started at 30 bpm for the first 40–45 minutes, then the HR began to increase. Surgery found a non-strangulating volvulus of the small intestine. The HR continued to progressively increase, and when it reached 65 bpm, the inhalant was switched to sevoflurane delivered at a concentration of 2% to 4%. Two liters of IV heta-

Shutterstock/nelelena

Teaching Points

starch were given to support the cardiovascular system and treat volume depletion.

A second blood gas was performed, which revealed that the metabolic acidosis (Table 1) was still present, lactate was 4.1 and the calcium had decreased from 1.5 to 1.299 mmol/L. The sevoflurane was increased due to the high HR. Dobutamine was discontinued at 1 hour and 30 minutes into the procedure due to a HR of 75 bpm. An additional 0.02 mg/kg of IV butorphanol was given for analgesia. The HR continued ModernEquineVet.com | Issue 3/2022

19

TECHNICIAN UPDATE

Distended small intestine seen with small intestinal issues

to increase to 85 bpm at 2 hours post-induction. Lidocaine and all other drugs had been discontinued except for the heta-starch and inhalant.

Surgery had progressed to closing of the linea alba. At this time, the author called Dr. Jane Quandt—the on-call anesthesiologist—due to the HR, as it could not be lowered. It was suggested to try an alpha-2 agonist drug.

Xylazine at 25 mg was administered for the analgesic and bradycardic effect. The HR decreased to 55–60 but the blood pressure dropped to 60 MAP and dobutamine was re-instituted. The HR began to increase again after 15-20 minutes. The hetastarch

infusion was complete, and fluids were discontinued after a total of 15 L. The respiratory rate was decreased to 5 bpm to wean the patient off the ventilator. Since there had been no reflux throughout the surgery, the nasogastric tube was removed, and was found to be patent.

Upon removal of the nasogastric tube, 4 to 6 L of spontaneous reflux came from both nostrils and the mouth of the patient. The HR subsequently dropped to 45-50 bpm.

The patient began trembling, 2 hours and 45 minutes post induction, so the following drugs were administered IV to provide sedation and analgesia: 0.38 mg/kg ketamine, 0.17mg/kg xylazine and 0.02 mg/kg butorphanol. The patient began spontaneous respirations, was hoisted into the recovery stall and placed in left lateral recumbency. Another 1 to 1.5 L of reflux came from the mouth and nostrils while the pony was being hoisted to the recovery stall. While the patient was still in the hoist with the head down, the mouth was rinsed to remove any remaining reflux.

In recovery, the patient was given 0.17 mg/kg of xylazine IV. A nasopharyngeal tube was placed to maintain an open airway, as there was nasal edema present.

Extubation was delayed until the patient was actively swallowing to prevent aspiration of fluid into trachea.

The patient’s recovery was assisted via head and tail ropes. Recovery was excellent: the patient was held down for the first several attempts and then allowed to stand on the first strong attempt. The pony walked back to the stall 60 minutes after discontinuation of the inhalant.

MeV

About the Authors:

Lori Dressel graduated in 1998 from St. Petersburg College with a degree in Veterinary Technology. From there, she completed a 6-month internship at Littleton Equine Clinic. She then joined the technical staff of the large animal and neonatal Intensive Care unit at The University of Pennsylvania for 3 years. She earned her Bachelors in Equine Business Management from Cazenovia College. For the following years, Lori held a position as a large animal anesthesia technician at the University of Georgia until 2013. In September of 2011, Lori earned her specialty in Large Animal Anesthesia and analgesia from the Academy of Veterinary Technician Anesthetists (AVTAA). As of 2015 she has been on medical leave.

Jane Quandt, DVM, MS, DACVAA, DACVECC, graduated from Iowa State University College of Veterinary Medicine in 1987. After doing small animal practice for 1 year, she did anesthesia residency. She completed an anesthesia residency and received a Masters in anesthesia at the University of Minnesota and became boarded in anesthesia in 1993. To improve her ability to manage critical cases she did a second residency in small animal emergency and critical care and became boarded in small animal emergency and critical care in 2007. She was on faculty at the College of Veterinary Medicine at the University of Minnesota for 10 years. She joined the faculty at The University of Georgia College of Veterinary Medicine in 2011 and is currently a tenured full professor in comparative anesthesia. She has published several journal articles and book chapters and has presented at national and international conferences on topics related to anesthesia and analgesia in both small and large animal species. Dr. Quandt was awarded the Carl Norden-Pfizer Distinguished Veterinary Teacher Award and the Zoetis Distinguished Veterinary Teacher Award.

20

Issue 3/2022 | ModernEquineVet.com

NEWS NOTES

USTA Microchips More Than 40,000 Standardbreds The United States Trotting Association (USTA) has microchipped more than 40,000 Standardbred racehorses in the U.S. using Merck Animal Health BioThermo microchips. USTA partnered with Merck in 2018 to become the first horse registry to formally incorporate temperature scanning into its microchip identification program. USTA is one of the largest users of Merck Animal Health’s Bio-Thermo microchips.

The USTA embraced the Bio-Thermo microchip because of its ability to serve not only as a dependable means of identification but also as an effective way for caretakers to record the horse’s body temperature at the scan of a microchip reader. This saves a significant amount of time over rectal thermometers and helps identify febrile horses sooner.

“We remain firm on the declaration that Bio-Thermo microchipping continues to provide the safest, most efficient and reliable means of identification that is also the most advantageous to the horse,” said TC Lane, chief operating officer, USTA. “This brings USTA in line with the international standard for equine identification. As an industry, we recognize that microchip technology is here to stay and view it as a win-win for our Standardbreds.”

Winbak Farm, one of the largest Standardbred breeding farms in the industry, has used the temperature-sensing microchip technology to keep track of its annual crop of more than 330 foals. Bio-Thermo microchips measure a horse’s temperature in seconds within one-tenth of a degree. With rectal thermometer readings estimated to take at least three minutes per horse,

this saves Winbak Farm more than 16 hours of labor.

Coupling the Bio-Thermo microchip with the new EquiTrace® horse health management app automates daily temperature charting and consolidates equine health record keeping—from managing mare ovulation status and logging therapeutic medications to estimating withdrawal times prior to race day. The USTA and its members are helping define the use cases and user experience for this innovative combination of the Bio-Thermo microchip and the app.

“I’m also excited about the EquiTrace technology, a tool that Winbak would love to integrate into its current systems,” said Jack Burke, farm manager. “The ability to pull up a horse’s complete history and add procedures in the field from your phone seems like something that anyone could get excited about.”

The Bio-Thermo microchip provides a 15-digit identification number, is about the size of a grain of rice, will not wear out and lasts the life of the horse. Both the EquiTrace app and Bio-Thermo microchips work with the Global Pocket Reader Plus and the HomeAgain® UWSR+ microchip readers. The secure, cloud-based, subscription-based EquiTrace app is available to download at the App Store or Google Play.

“USTA has become a beacon to the industry by embracing this unique identification technology to advance health and well-being in Standardbred racing,” said Ron McDaniel, director of U.S. equine sales, Merck Animal Health. For more informataion, visit www.merck-animal-health-usa.com/species/equine.

MeV

Variation Seen Among People Assessing Equine Pain Owners and veterinarians do not always agree about the degree of pain a horse might be in, according to a new study.

Researchers conducted a cross-sectional study to compare the estimates of pain experienced by horses by veterinarians and horse owners to determine what factors were associated with their perceptions of equine pain.

Owners and veterinarians completed internet-based questionnaires, which included questions related to recognition of pain in horses, estimated degree of that pain and demographic information. The researchers used logistic regression to assess the variables associated with perception of a high or low degree of pain based on the responses of 553 owners and 263 veterinarians.

Pain scores varied widely, and differences in median scores from horse owners and veterinarians were small.

Horse owners providing high pain ratings were more likely to own fewer than 10 horses, and they tended not

to hold a college degree. Those providing low pain ratings tended to own more horses than those who gave animals higher ratings.

Veterinarians providing high pain ratings were more likely to be employed in a mixed-animal practice and to lack board-certification in a veterinary specialty. Those giving low pain ratings were more likely to be men.

An important step toward improving communication between veterinarians and horse owners is to understand the factors that influence attitudes and beliefs about pain severity so that communication and consensus-building may be facilitated.

MeV

For more information: Sellon DC, et al. Pain severity scores for common as provided by horse owners and equine veterinarians.

Equine Vet. J. 2022 Jan. 16. https://beva.onlinelibrary.wiley.com/doi/10.1111/evj.13559

ModernEquineVet.com | Issue 3/2022

21

BUSINESS OF PRACTICE

Now, Later, or Never: Evaluating Your Practice for Sale or Other Options

By Cath Paulhamus Business has been booming for equine veterinary practices during the pandemic, according to Mike Pownall, DVM, MBA, a partner at McKee-Pownall Equine Services.

Working from home and unable to vacation, clients are spending more time with (and money on) their horses, Dr. Pownall said at the 67th AAEP Annual Convention. The profession is busier than normal, but

often working with fewer staff—and not enough graduating veterinarians are joining practices.

In this environment, older or long-term practice owners are facing burnout as they work to keep up with the demands of treating patients and running a business.

At the same time, corporate groups have stepped up their offers to acquire equine practices. As Dr. Pownall explained, these groups have been making exceptionally high offers, sometimes in the range of 15 times EBITDA (earnings before interest, taxes, depreciation, and amortization). These attractive offers are prompting practice owners to consider exit strategies earlier than they planned. Would it be better to sell to a corporate consolidator now, in this market, before these opportunities pass? If the owner is not ready, what are some alternative business models that can help ease workload, improve cash flow and ensure the practice (and its reputation) will endure?

22

4

Issue 3/2022 | ModernEquineVet.com

When considering the financial impact of selling (or merging) one’s practice, it’s critical to understand how veterinary practices are valued—and how to prepare for it. Sometimes it’s a better strategy to postpone a few years with the goal of positioning the practice for a higher valuation.

Dr. Pownall explained that offers are usually based on multiples of EBITDA. In the past, it was usually 4 or 5 times, but in the current competitive market, it’s now up to 10- or 15-times EBITDA. A higher multiple indicates a lower perceived risk for the buyer. Before selling, owners can improve their position, not only by increasing their EBIDTA, but also by ameliorating aspects of the practice that appear “risky.”

WAYS TO INCREASE THE VALUE OF YOUR PRACTICE

The greater the cash flow, the greater the value. If possible, practice owners should work to increase EBITDA and reduce debt before selling by: 1. INCREASING REVENUE (for example, raising fees) 2. LOWERING EXPENSES by controlling inventory, employee turnover, etc.

3. AVOIDING CASH PAYMENTS or bartering from clients (which reduces the documented revenue of the practice) 4. CONTROLLING owner’s expenses.

Shutterstock/Visual Generation

Valuation Factors

DON’T LEAVE YOUR BREEDING PROGRAM UP TO CUPID

REDUCE THE STRUGGLE.

The only product researched to improve conception rates in difficult to breed mares.

Take your breeding program to the next level with this research-backed Omega-3 formula providing reproductive health benefits for mares, stallions, and foals. Releira addresses common fertility issues with a readily absorbed, vegetarian algae source.

Not only reduce the cycles to conception for your difficult mares but improve semen quality in those stallions with morphology and motility issues. Research proven to improve cognitive abilities in the newborn foal.

References: [1] Brendemuehl JP, Kopp K, Altman J. Uterine Inflammatory Response to Frozen Semen is attenuated by Oral Supplementation of a Blend of Omega-3 Fatty Acids (Algal DHA and Flax Seed) in Susceptible and Resistant Mares. Submitted to Theriogenology. [2] Brendemuehl JP, Altman J, Kopp K. Influence of dietary algal N-3 fatty acids on breeding induced inflammation and endometrial cytokine expression in mares bred with frozen semen. J Equine Vet Sci. 2014; 34(1): 123-124. [3] A.M. Adkin, A.V. Muniz, C.J. Mortensen, L.K. Warren. Maternal fatty acid supplementation influences memory and learning ability in yearling and 2-year-old horses. J Equine Vet Sci. 2015; 35: 418-436. [4] A.M. Adkin, L.K. Warren, C.J. Mortensen, J. Kivipelto.

Maternal supplementation of docosahexaenoic acid and its effect on fatty acid transfer to the foal (longitudinal study). Equine Vet Sci. 2013; 33: 321-329. [5] A.M. Adkin, L.K. Warren, and C.A. McCall. Effect of maternal docosahexaenoic acid supplementation on behavior and cognitive development in nursing foals. J Equine Vet Sci. 2013; 33: 321-399.

Ask your Veterinary Solution Specialist how Releira can take your patient’s breeding program to the next level.

Arenus Animal Health | 866-791-3344 | www.arenus.com

ModernEquineVet.com | Issue 3/2022

23

BUSINESS OF PRACTICE

ALTERNATIVE BUSINESS MODELS If the owner doesn’t need the assurance of selling quickly in the current environment, there are new business models evolving in the industry, such as a management company, shared ownership, franchise, and merger. “These are not just hypothetical models we thought of,” Dr. Mike Pownall said. “These are actually being used in the real world right now.” Choosing between the options depends on an owner’s career stage, amount of control one wants to retain, and how one views collaboration—and whether one is looking for expanded business opportunities.

Unfortunately, currently, there are few options to bring in young veterinarians or staff into ownership positions. Therefore, stakeholders want to see practice management move forward at the highest professional level, for all those committed to equine care.

According to Dr. Pownall, a partner at McKee-Pownall Equine Services, important features of these options include: • the ability to attract and retain staff • economies of scale (shared purchasing, administrative support) • increased profitability (EBIDTA) • decreased risk • options for an exit strategy.

Management company. Practices that decide to work collaboratively may create a management company to handle administrative burdens, such as payroll, marketing and insurances. The assets and value remain with the management company, which can be owned by the veterinarians or even staff members, and it has a contract with each of the practices stating that most of the combined profit flows to the management company. This pool of resources allows for better health insurance, purchasing power and other services.

Shared ownership. In this model, there is also a management company, but with shared ownership among all the participating practices (each one owns shares of each entity). For example, there could be a central hospital hub, surrounded by satellite clinics. “By owning a little bit of each other, we’re incentivized to make sure that other clinics and the hub are doing well,” Dr. Pownall said. “You don’t mind referring because you have a stake in it, and when they do well, you do well.”

Franchise. Practices that have developed something special or innovative may want to replicate that idea and expand to areas with untapped opportunities. Owners can scale and monetize what they’ve established. Or provide an associate with a way to jump start a new practice. With franchise models, owners can sell their concept for an initial fee plus ongoing royalties The parent company handles equipment, marketing and brand management, along with other core support systems.

Merger. Multiple practices with synergies can merge, working together and sharing resources such as equipment, but functioning independently under a management company. They can be sold eventually as one company.

When reviewing financials, corporations will “normalize” the practice’s EBITDA by comparing it with industry norms in the area. For example, if the practice is underpaying staff, the numbers will be adjusted to be in line with average salaries (thereby, lowering the practice valuation), he explained. In addition, buyers prefer consistent revenue growth and EBITDA, over 3 years, rather than extreme changes in either direction.

Corporations are essentially buying future cash flow, which depends on a number of factors—not all of them financial, according to Dr. Pownall. For example, is the practice losing or gaining clients?

Are there enough veterinarians in the practice to maintain its reputation? A practice with a reputation based on 1 owner-veterinarian might not retain loyal clients when the owner retires.

24

Issue 3/2022 | ModernEquineVet.com

Another factor to consider is staff retention—are they likely to stay and provide consistent, personalized service to help retain clients if ownership changes?

Once an owner has considered how the practice will be valued, personal/professional goals come into play.

Is she or he close enough to retiring? How will this decision affect personal relationships with clients and staff?

Is corporate ownership of equine practices a positive model for the profession? Corporate owners are in the business of selling at a higher value, Dr. Pownall said.

“For veterinarians, making money is helpful, but we’re also there to take care of pets. Sometimes we make decisions on what’s best for the pet as opposed to what’s best for the business financially. Maybe it’s better for the reputation of the business, or we want to take care of a particular client . . . we need to make money, but we have other goals, too.”

MeV

INFECTIOUS DISEASES

Discovery of New Hendra Virus Variant in Horses a Lesson in Emerging Disease Surveillance A new variant of the Hendra virus was identified by Sydney-led research as a cause of fatal illness in Australian horses, and of risk for virus spillover into humans.

Hendra virus circulates among flying foxes and is fatal to horses and people. All flying-fox species in Australia are capable of being infected with the virus and may transmit it to people through spillover infection of domestic animals through exposure to infected fluids, such as urine. Flying foxes are a protected species, critical to the environment because they pollinate native trees and spread seeds.

Since 1994, there have been 7 human cases, 4 of which were fatal, and all had been exposed to horses infected with Hendra virus.

The new variant of the Hendra virus was found in a laboratory sample from a Queensland horse that died an unexplained death in September 2015.

Although the veterinarian suspected Hendra virus, routine screening and diagnostic tests were unable to confirm any diagnosis, as they were designed to test for already known Hendra virus strains.

Samples from the Queensland horse were stored in a state laboratory, alongside samples from horses that were routinely tested for disease. In 2021, using next generation sequencing, the team confirmed the Queensland horse's cause of death as a previously unrecognised Hendra variant.

The researchers alerted veterinarians and Australian laboratories and collaborated with U.S. partners to confirm that the current treatments would be equally effective in protecting against the new Hendra virus strain.

The researchers said the discovery demonstrates the importance of extensive biosecurity and surveillance programs that mirror the complexity of emerging viruses, such as examining areas and scenarios where new viruses are likely to come into contact with susceptible domestic animals and people, such as veterinarians. This is the foundation of the “Horses as Sentinels” program, which led to the detection of this variant.

Detection of the new variant resulted from a 7-year effort to create a network of frontline veterinarians, molecular biologists and virologists aiming to detect new viruses in domestic species. This One Health network also included researchers in the United States. Researchers

share field and clinical observations and combine multiple laboratory techniques in parallel.

“This virus was different enough to avoid the established routine testing and screening,” said Edward Annand, BVSc (Hons), MANZCVS (Equine Surgery/ Epidemiology), CertAVP (ESM), PgCert VPS, MRCVS, from the Sydney School of Veterinary Science.

The researchers found that more than 93% of horses that were tested for Hendra virus were in regions where spillover had previously been detected (eastern Queensland and Northeastern New South Wales), meaning there was reduced scope for detection outside these areas.

There has been a general misconception that Hendra virus cases only occur in these areas, and that has served as a barrier to investigating this disease, according to Dr. Annand, adding that the new variant was detected near Newcastle, central New South Wales, and it reinforces the need for broader testing.

“The good news is that the scientific findings support our understanding that the current equine vaccine will be equally effective against this strain, meaning reliable mitigation of human health risk is available via immunization of horses,” Dr. Annand said.

The new Hendra variant is not the only novel spillover that the collaborative team has uncovered. Previously, Dr. Annand facilitated detection of spillover of Australian bat lyssavirus to horses.

MeV

For more information: Annand EJ, Horsburgh BA, Xu K, et al. Novel Hendra Virus Variant Detected by Sentinel Surveillance of Horses in Australia. Emerg Infect Dis. 2022;28(3):693. https://wwwnc.cdc.gov/eid/article/28/3/21-1245_article

ModernEquineVet.com | Issue 3/2022

25

The Modern

Equine Vet Reach your veterinarians wherever they are, whenever they want.

FOR ADVERTISING RATES AND INFORMATION, EMAIL Matthew Todd or Matthew Gerald