The Modern Equine Vet January 2016

The Modern

Equine Vet www.modernequinevet.com

Vol 6 Issue 1 2016

AAEP Meeting:

The State of the Industry Fine tuning doping tests Oxygen before anesthesia?

Technician Update: Standing MRI, stem cells to improve lameness

Table of Contents

Cover story:

State of the equine

4 industry

Cover photo Shutterstock/Makarova Viktoria

sports medicine

Fine tuning doping tests........................................................................................................8 Genetics

Unlocking genetic secrets of the Dunn coat.................................................................10 technician update

Standing MRI, stem cells help put the spring back into jumper's step..............12 News

Horses tolerate preanesthetic oxygen......................................15 Sunshine vitamin linked to improved fertility in wild animals...................................................................15 Controlling mosquitoes? Watch the flowers...........................16 CT proves useful in diagnosing conchal bullae disease............17 UK vets' antibiotic prescribing habits........................................18 BI strengthens position in animal health................................19 advertisers Universal Imaging....................................................... 3 VetStem.......................................................................... 5 Merck Animal Health.................................................. 7

Hallmarq........................................................................ 9 AAEVT............................................................................13

The Modern

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

2

Issue 1/2016 | 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.

UNIVERSAL IMAGING

Universal Imaging See the difference

TM

TRANSFORM THE QUALITY OF CARE Innovative Mobile Solutions For Today’s Equine Practitioner

Ultrasound

Digital Radiography

Cloud & PACS

Leading-edge systems tailored to the equine practitioner.

Ultra-light, fully wireless systems with auto X-ray detection technology.

Comprehensive cloudbased image storage and management.

BUY THIS

Continued Education Focused on improving the quality of care that you offer your patients.

GET THIS FOR $10,000

myRad D-EVO Digital Radiography

ULTRA-LIGHT DIGITAL RADIOGRAPHY FOR TODAY’S EQUINE PRACTITIONER.

ULTRA-PORTABLE ULTRASOUND DESIGNED FOR VETERINARY MEDICINE 15 lbs.

6 lbs.

FujiFilm’s sophisticated imaging technologies and advanced processing bring the image quality of myRad D-EVO to the next level.

Compact, powerful and easily transportable, EXAGO offers veterinary practices exceptional image quality and unparalleled ease-of-use.

ISS Technology improves signal strength and dose efficiency, resulting in images with an unprecedented level of diagnostic content.

Best image quality of any 6-lb. system - B, B+B, B+M modes, Color Flow Mapping, Pulsed Wave-Power Doppler, Cardiac, Video Clips, MSK – All Standard

SmartSwitch (AED) Technology eliminates generator synchronization problems by automatically sensing x-ray photons to initiate image acquisition.

Industry leading battery run time of up to 6 hours enhances the portability by eliminating the need for a power source.

EQUINE PRO PACKAGE SPECIAL

Purchase a myRad-DEVO with a C24i (10x12) or P35i (14x17) detector before February 15, 2016 and get an EXAGO ultrasound with one probe for $10,000, PLUS a free one or two day VetPD Continued Education course held anywhere in the world.

CLICK HERE TO LEARN MORE

800.842.0607 | www.universalimaginginc.com

cover story

tate of the equine industry

Despite a rebound after the downturn, equine veterinarians have not seen a complete recovery.

B y

Shutterstock/prettyboy80

There was a significant

4

downturn in key economic indicators for equine practices from 2008 to 2010, including revenues, invoices and number of active patients and clients. This was followed by a rebound in 2011 and 2012, but not a complete recovery, according to the National Equine Veterinary Economic Study, sponsored by Merck Animal Health and Henry Schein Animal Health, in partnership with the American Association of Equine Practitioners (AAEP).

All measures of economic activity such as total revenue, number of patients, number of clients

Issue 1/2016 | ModernEquineVet.com

P a u l

B a s i l i o

and number of transactions or invoices declined significantly through the Great Recession and rebounded somewhat in 2011 and 2012, according to equine veterinary market research specialist and practice management consultant, Edward L. Blach, DVM, MS, MBA, and assisted by Andrew R. Clark, DVM, MBA, leading equine practice management consultant, who lead the study.

The study was a much-needed snapshot of the industry from 2007–2012. Some of the findings in the study were expected, but much of the data are surprising and, in some cases, sobering, they

said at a press briefing at the 61st AAEP Annual Convention and Trade Show, held in Las Vegas.

Practice owners made very few adjustments to payroll or labor head count through the recession.

Instead, they shouldered much of the impact of the recession by taking less in compensation themselves.

The market has fundamentally changed since the survey began in 2007. The potential pool of clients is smaller, and there are fewer horses to treat. Most practitioners are likely doing more with those clients and those horses, but there are other good expansion oppor-

Stem Cells for Bleeders VetStem has launched an Investigational Clinical Research program for Exercise Induced Pulmonary Hemorrhage (EIPHBleeders) What’s the Problem?

Exercise induced pulmonary hemorrhage (EIPH, aka “bleeders”) occurs in the majority of strenuous exercise performance horses. EIPH has a negative effect on athletic performance. It is defined as the presence of blood in the bronchi and/or trachea that is detected on endoscopic exam after intense exercise.

Preliminary Outcomes We are excited to release the first round of preliminary data for our Bleeders (EIPH Exercise Induced Pulmonary Hemorrhage) Clinical Research Program. We have outcome data on six of the horses, and as we had hoped, the results look very promising.

Below are the results.

Results: Six horses have completed their first competition as of this date, and all six have competed again without any preventative medications after adipose stem cell therapy (ASCs).

I’m interested, what should I do?

Contact Karina Benish, RVT (kbenish@vetstem.com) at VetStem for more details and approval.

VetStem will offer a reduced cost program during the initial data gathering period. We would like to enroll a total of 30 horses during this initial research program.

TEL: 858.748.2004 ▪ TOLL FREE: 1.88.VETSTEM1 ▪ WEB: www.Vet-Stem.com

cover story

The good, the bad, and the slightly embarrassing

13

o f equine practices belong to a study group—a much higher percentage than in companion animal practices.

14 16% 18% 31% 32% 60%

use a practice management consultant.

70 73%

of practices use practice management software.

% %

%

of practices have a formal budget. of equine practices have written practice goals. of practices lock their pharmacy door. of practices have a mission statement. of practices use email communication, but most of those practices do not have anywhere close to a full client e-mail list.

of practices text clients, which may create a problem as there is no record of those texts in the medical record.

Practitioners can create a free account on www.IsMyPracticeHealthy.com, a simple, non-intimidating portal for the results of the National Equine Veterinary Economic Study and other practice management information. The site offers daily, fresh, brief pieces of management education for veterinarians.

6

Issue 1/2016 | ModernEquineVet.com

tunities available, they said.

Too few practices used modern management principles to manage their practices with intent to optimize profit and enterprise value.

Many opportunities exist for most practices to improve profitability and to grow the value of their practices.

“In the past, we have not had access to a lot of economic data in the equine veterinary industry,” explained Dr. Blach. “We went into the study with the assumption that we needed to find a way to get this information out to the practice owners so they could put it to use.”

Dr. Clark noted that while there is some good news in the study, some of the data are unsettling.

“Only 16% of practices use a formal budget,” he explained. “Only 31% of equine practices lock their pharmacy door. That means there are tens or hundreds of thousands of dollars in drugs and supplies sitting in an unlocked room.”

Dr. Clark added that evercrowded curriculum in universities has been squeezing out the opportunity to learn about the business side of veterinary medicine.

“This year’s graduates know more but are good at less than anyone who has ever graduated.

Next year’s class will know even more but will be good at even less,” he said. “The light at the end of the tunnel is the student-driven Veterinary Business Management Association [VBMA]. It has a curriculum, the students receive a certificate at the end, and it’s the primary opportunity to get a business education in veterinary school. However, the necessity of a student club to teach business should be somewhat embarrassing to the universities.”

Prior to the Great Recession, there was a sense that there was enough equine business to go

around for everyone. Many practitioners put their head down, went to work every day and did not worry too much about closely managing their practice.

“They could get by because there was enough work,” Dr. Blach said. “I don’t believe that’s the case now. There is more competition for the available work, and fewer horses among the owners who are there. It’s more important than ever to manage for profitability.

There were practices during the recession that had the most profitable years they’ve ever had, but those are the ones who managed their practices more closely.”

Overall, the study sheds a lot of light on business opportunities that have been overlooked by some veterinary practitioners, according to Brett Whitehead, director of Equine, Merck Animal Health. “In some instances, making a few immediate changes [as a result of the study] will equate to quick wins for the clinic and its customers.”

Jeannie Jeffery, national director of Equine Sales, Henry Schein Animal Health, and one of the early supporters of the study, noted that the study tells a great deal about the issues facing equine practitioners as they navigate the challenges inherent to running a business.

“Through a greater understanding of their needs, we can ensure that we are offering the products, services and solutions for operating an efficient practice and delivering quality care,” she said.

Veterinarians are trained to provide the best possible patient outcomes, Dr. Clark said. “As far as the financial outcome, we’re not trained for that. We would refer a sick horse to a board-certified specialist if the outcome warranted it. If we look at the health of our practice, we should refer it to someone who specializes in pracMeV tice health.”

Some dewormers claim just one dose of their product is the best way to deworm your horse, but that’s simply not true.

Demand Safety: You won’t find a laundry list of warnings and precautions on the PANACUR® (fenbendazole) POWERPAC label, like those other dewormers, because fenbendazole has a unique mode of action that makes it safe for horses of all ages, sizes and body conditions.

Demand Efficacy: PANACUR POWERPAC is the only dewormer FDA approved to treat ALL STAGES of the encysted small strongyle.1 Other dewormers miss a critical stage, EL3, which can account for up to 75% of the encysted small strongyle burden. Plus, it’s the best choice for treating ascarids – which are not just a problem in young horses!

SO WHEN IT COMES TO WHICH DEWORMER TO TRUST, DON’T FORGET THERE’S SAFETY IN NUMBERS. Consult your veterinarian for assistance in the diagnosis, treatment, and control of parasitism.

Do not use in horses intended for human consumption. When using Panacur® (fenbendazole) Paste 10% concomitantly with trichlorfon, refer to the manufacturers labels for use and cautions for trichlorfon.

PANACUR (fenbendazole) POWERPAC Equine Dewormer product label. © 2016 Intervet Inc., d/b/a Merck Animal Health, a subsidiary of Merck & Co., Inc. All rights reserved.

1

sports medicine

Fine tuning

Doping in the horseracing

industry has spurred regulations banning performance-enhancing drugs, as well as calls for an antidoping agency in the United States.

But as in human sports, testing for certain kinds of prohibited substances has been a challenge. Now scientists report in ACS' journal Analytical Chemistry a new detection method that could help anti-doping enforcers determine whether a horse has received certain substances.

To give their animals an edge on the track, some individuals might administer a single substance, a cocktail of hormones, hormone-mimicking compounds or other drugs. Most are

8

Issue 1/2016 | ModernEquineVet.com

prohibited in the racing industry, but catching violators can in some cases be difficult with conventional methods. Existing techniques directly test for the original compounds administered to an animal or their unique metabolites or byproducts. But some of these substances can get processed and eliminated by the animal quickly, making the window for detection very short. George Ho Man Chan, Terence See Ming Wan and colleagues are investigating unconventional ways to increase the chances of catching cheaters.

The researchers have identified seven biomarkers in urine that potentially indicate whether a horse has been given aromatase inhibitors,

a class of compounds also used by bodybuilders to help regulate hormones and get an edge on the competition. Testing for the changes in these naturally occurring biomarkers in horse urine could reveal the administration of the substances for about 95 to 195 hours after injection. That's two to 2.5 times longer than conventional screening methods. Being able to find evidence for the administration of these drugs for two or more days longer than before could increase the chances that ruleviolators will be caught. With further validation studies, this method could be developed into a useful screening tool for detecting the use of aromatase inhibitors in horses.

MeV

Shutterstock/Sukhanova Daria

doping tests

COMPLEX LAMENESS CASE ?

DON’T BE LEFT IN THE DARK, CONSIDER STANDING EQUINE MRI

www.hallmarq.net

Standing Equine MRI

Genetics

Unlocking Genetic Secrets

of the Dun Coat in Horses

Photo courtesy of Freyja Imsland

Although horses come in a

variety of coat colors, most lack the camouflaging coat of their ancestors. However, a trace of that legacy remains in horses with the dun pattern, which is characterized by pale hair covering most of the body, a dark stripe along the back and zebra-like stripes on the legs.

A recent study revealed a new mechanism that explains the genetic roots of the dun pattern and uncovers why the pattern does not appear in most domesticated horses—it’s been bred out. The study is the work of an international team of scientists led by Texas A&M

University Institute for Advanced Study (TIAS) scholar Dr. Leif Andersson and is the result of a collaboration among groups at Texas A&M University, Uppsala University in Sweden, and the Huntsville Institute of Biotechnology in Alabama.

The dun pattern camouflaged ancient wild horses, protecting them from predators. However, domestic horses—like other domestic animals—have been selected over many generations to appear different from their wild counterparts. As a result of selective breeding, most domestic

horses today are not dun and have coat colors that are more intensely pigmented and uniformly distributed across the body.

“Dun is clearly one of the most interesting coat color variants in domestic animals because it does not just change the color but the color pattern,” Dr. Andersson stated. “We were really curious to understand the underlying molecular mechanism of why the dun pigment dilution does not affect all parts of the body.”

“Unlike the hair of most wellstudied mammals, the dilutecolored hairs from dun horses are

Three Dun stallions.

From left: Bay dun, blue dun, and red dun.

10

Issue 1/2016 | ModernEquineVet.com

not evenly pigmented,” explained Freyja Imsland, a PhD student in Dr. Andersson's group. “They have a section of intense pigmentation along the length of the hair, on the side that faces out from the body of the horse, while the rest of the hair has more or less no pigment. The hairs from the dark areas of dun horses are in contrast intensely pigmented all around each individual hair. In spite of scientists having studied hair pigmentation in detail, this kind of pigmentation is novel to science and quite unlike that seen in rodents, primates and carnivores.”

Genetic analysis and DNA sequencing revealed that the dun color is determined by a single gene, which codes for the T-box 3 (TBX3) transcription factor, which controls several critical processes in development that affect bones, breast tissue and cardiac conduction, according to Dr. Greg Barsh, whose group at Huntsville led the tissue analysis. “We were surprised to find that

TBX3 also plays a critical role in skin and hair development.”

Researchers measured TBX3 distribution in individual hairs relative to other molecules known to regulate pigmentation. They suggested that the signals governing where TBX3 is expressed could help to explain zebra stripes. In horses that have lost their dun color, TBX3 mutations do not inactivate TBX3 protein function and instead only affect where—both on the individual hair and on the horse’s body— the gene is expressed.

“In growing hairs, TBX3 mirrors the distribution of melanocytes, the cells that produce pigment,” explained Kelly McGowan, a senior scientist in Dr. Barsh’s lab.

“Our results suggest that TBX3 affects differentiation of specific cells in the hair, creating a microenvironment that inhibits melanocytes from living in the ‘inner’ half of the hair.”

The team also discovered that there are two forms of dark, non-

dun color: non-dun1 and nondun2, which are caused by different mutations. Non-dun1 horses differ from dun horses in that they have a darker coat and less contrast between the stripes and the rest of the body. On the other hand, non-dun2 horses show no stripes at all.

The study results indicated that the non-dun2 variant occurred recently—most likely after domestication. In contrast, the dun and non-dun1 variants predate domestication. Evidence of this conclusion can be found in the DNA of a horse that lived about 43,000 years ago—long before horses were domesticated—which carried both dun and non-dun1 variants.

“This demonstrates that horse domestication involved two different color morphs—dun and non-dun1—and future studies of ancient DNA will be able to reveal the geographic distribution and the abundance of the two morphs,” Dr. Andersson said.

MeV

For more information: Imsland F, McGowan K, Rubin CJ, et al. Regulatory mutations in TBX3 disrupt asymmetric hair pigmentation that underlies dun camouflage color in horses. Nature Genetics 2015 Dec. 21 [Epub ahead of print].

Sign up today * We promise not to bombard you with emails. Just a notice when new information is available.

Send us your email address

ModernEquineVet.com | Issue 1/2016

11

technician update

Standing MRI, stem cells help put the spring back into jumper's step

By Nicole LaGrange, RVT An 11-year-old Warmblood gelding used for hunter jumper competition presented in October 2014 for lameness after jumping the day before. He had been purchased approximately one month prior to the onset of this injury after a thorough prepurchase examination during which no abnormal findings were discovered.

On clinical examination, the horse showed no significant findings upon palpation and inspection of the limbs with the exception of mild left-front proximal suspensory pain upon deep palpation. He was negative to hoof testers. Digital pulses were normal. Neck and back palpations were considered unremarkable.

Examination on the lunge line on soft ground revealed a left forelimb 3/5 lameness on the circle right and 1/5 lameness on the circle left, the lameness was less apparent when lunging on hard ground in both directions.

Flexion tests revealed 2/5 on the left front fetlock, 2/5 right front fetlock, 3/5 left hock, and 3/5 on the right hock.

Distal nerve blocks did not resolve the left front lameness (PD, fetlock, and low 4-point performed).

After local anesthesia infiltration of the proximal suspensory origin, the gelding showed 100% improvement 5 minutes post injection. Advanced imaging was recommended.

November 2014 scintigraphy revealed in the soft tissue phase an “increased radiopharmaceutical uptake in the left distal carpus and proximal metacarpal region, moderate to severe and focal in the region of the palmar soft tissues.” The bone phase of the scan revealed “Left palmar distal carpus and proximal metacarpal region, severe and focal.”

Diagnostic ultrasound was performed and interpreted as normal. Radiography examination of the left metacarpus and carpus was performed and revealed the trabecular pattern of the proximal medial third metacarpus was mildly sclerotic.

Based on these findings, the horse was recommended for standing magnetic resonance imaging (MRI, Hallmarq) of the left front proximal metacarpal region. Findings enumerated on the radiologist report included “moderate fluid of the third metacarpal bone of the left fore and mildly irregular palmar 12

Issue 1/2016 | ModernEquineVet.com

Nuclear scintigraphy

Initial MRI

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

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

Bi-Annual Newsletter Weekly “HoofBeats” Email Newsblast Full access to www.aaevt.org, including the Career Center and the Library Up-to-date information on the AAEVT Discounted registration for AAEVT Regional Meetings and the annual AAEP/AAEVT Convention NTRA, Working Advantage and Platinum Performance Benefits The opportunity to participate in the AAEVT Online Certification Program or to become a member of the AEVNT Academy-Specialty in Equine Veterinary Nursing Scholarship opportunities.

AAEVT’s Equine Manual for Veterinary Technicians (Blackwell Publishing 20% discount on purchase price) Opportunity to attend Purina’s Annual Equine Veterinary Technician Conference - All Expenses paid!

AAEVT Objectives • • • •

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

AAEVT Online Equine Certification Program

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

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

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

*American Association of Equine Veterinary Technicians and Assistants

Proximal suspensory syndrome is a complex of several interrelated pathologies that require careful management.

MRI after treatment

margin, third metacarpal bone, left fore.”

The veterinarian recommended a follow-up MRI in 6 weeks to ensure that the healing was progressing normally and to rule out any soft tissue injury development, as well as to assess the osseous fluid in the third metacarpal bone.

In addition, the veterinarian decided the horse was a good candidate for stem cell therapy. Stem cells are regenerative cells that can differentiate into many tissue types, as well as reduce pain and inflammation thus helping to restore range of motion and stimulate regeneration of tendon, ligament and joint tissues. Stem cell harvest was performed using the bilateral gluteal liposuction technique. The fatty-tissue was sent to Vet Stem lab in San Diego for processing. Once processed, the stem cells are quality checked and then injectable doses of the patient’s stem cells are returned. Two days later, the stem cells were injected periligamentous at the proximal suspensory origin.

The horse received stall rest for 30 days with twice daily NSAIDS, 30-minute hand walks and 20 minutes of ice therapy.

14

Issue 10/2015 | ModernEquineVet.com

Additional stem cells were injected periligamentous at the proximal suspensory origin in December 2014. Follow-up examination showed that the horse was sound at the trot in a straight line and on the lunge line on hard ground without using NSAIDs. He showed mild sensitivity to firm palpation of the proximal suspensory origin of the left front. At this point it was advised to turn the horse out in a small paddock and continue hand walking and cold therapy until his recheck MRI in February.

In February 2015, recheck MRI findings included “resolved fluid, third metacarpal bone, left fore, focal mild to moderate sclerosis, third metacarpal bone, left fore, and mildly irregular palmar margin, third metacarpal bone, left fore.”

March 2015, following the recheck MRI a series of shockwave therapy treatments of the left front proximal suspensory region were begun at monthly intervals for six months. Concurrently, tiludronate disodium (Tildren, Ceva) was administered (1 vial IV) at each shockwave session.

Additionally, it was recommended that the patient be started under saddle walking 20 minutes per day the first week, and beginning the second week, add in trot-work at 2 minutes additional per week. Each afternoon the gelding was walked for 30 minutes. After 6 weeks (12 minutes of trot-work per day) he began the canter-work at 2 minutes per week, adding 2 additional minutes each week. He was allowed turn out daily. Aspirin at one scoop twice daily was started.

As of July 2015, the gelding was in full flatwork and had started jump schooling and remains sound.

Proximal suspensory syndrome is a complex of several interrelated pathologies that require careful management.

MeV

About the author

Nicole LaGrange, RVT, is a veterinary technician with San Dieguito Equine Group in San Diego, Calif. She works in the field as well as performing standing MRI for the clinic. Her primary interests are in sport horse management including lameness and imaging. Ms. LaGrange is a regional contact for AAEVT.

news notes

Horses tolerate pre-oxygenation before general anesthesia

Photo courtesy of the Equine Veterinary Journal

Pre-oxygenation via a nasal cannula before induction of general anesthesia is well tolerated, results in significantly increased arterial oxygen levels in the immediate post-induction period and does not increase intrapulmonary shunting, according to a recent study.

Although performed in other species, there are no reports of the use of oxygen supplementation in horses prior to anesthetic induction. This randomized prospective clinical trial set out to determine whether pre-oxygenation via a nasal cannula raised arterial partial pressures of oxygen following induction of general anesthesia. Nine healthy adult horses were given oxygen at a flow rate of 15 L/min for 3 minutes prior to anesthetic induction. In nine controls, the na-

sal cannula was inserted but oxygen was not given.

All horses received the same premedication and were induced with ketamine and midazolam before being placed in left lateral recumbency. The horses were intubated, attached to a circle breathing system and then received isoflurane and oxygen with an inspired oxygen fraction of 50% at a flow rate of 4–6 L/min. During this time the horses were breathing spontaneously.

Immediately after induction, the PaO2 measured in the oxygenated group was significantly higher than in the control group. Only one animal in the oxygenated group had PaO2 less than the level at which intervention to treat hypoxemia is deemed necessary, in contrast to the control group in which all but one had PaO2 below this cut-off value (8–9.3kPa).

There was no significant difference in PaO2 of the two groups in a 30-minute sample and there was no significant difference in intrapulmonary shunt fraction between groups, indicating it was unlikely that oxygen supplementation results in intrapulmonary shunts via resorption atelectasis. Acceptance of the nasal cannula was scored as “moderate” in two horses and described in all the others as “good.”

More study is required to determine whether using this method results in better clinical outcomes, the researchers said.

MeV

For more information: Van Oostrom H, Schapp MWH, Van Loon JPAM. Oxygen supplementation before induction of general anesthesia in horses Equine Vet J. 2015 Dec 25. [Epub ahead of print] Getting ready for surgery. Should it include pre-induction oxygen?

http://onlinelibrary.wiley.com/enhanced/doi/10.1111/evj.12526/

Sunshine vitamin linked to improved fertility in wild animals High levels of vitamin D are linked to improved fertility and reproductive success, a study of wild sheep has found. The study, carried out on a remote Hebridean island, adds to growing evidence that the sunshine vitamin is associated with reproductive health.

Researchers led by the University of Edinburgh measured vitamin D concentrations of an unmanaged population of Soay sheep. They found that sheep with higher blood levels of vitamin D at the end of the summer had more lambs the following spring. The study offers the first evidence that an animal’s

vitamin D status is associated with an evolutionary advantage.

Vitamin D is essential for healthy bones and teeth and has been linked to other health benefits.

Laboratories have linked vitamin D to reproductive health in domestic animals and humans. This is the first evidence of the link in wild animals. Scientists carried out the research as part of a longterm study on the evolution of Soay sheep, which have lived wild for thousands of years on the islands of St Kilda, a world Heritage site owned and managed by the National Trust for Scotland. MeV

For more information: Handel I, Watt KA, Pilkington JG, et al. Vitamin D status predicts reproductive fitness in a wild sheep population. Scientific Reports 2016 [Epub Jan. 13] http://www.nature.com/articles/srep18986 ModernEquineVet.com | Issue 1/2016

15

news notes

Controlling mosquitos? Watch the flowers Certain mosquitoes are more likely to lay eggs in water sources near flowers than in water sources without flowers, according to an article published in the Journal of Medical Entomology.

Researchers from the Department of Agriculture and the University of Florida studied the Asian tiger mosquito (Aedes albopictus) and its egg-laying preferences. This mosquito transmits West Nile virus and Eastern equine encephalitis, canine heartworm, as well as human diseases, such as yellow fever, dengue and chikungunya, and it has been spreading throughout the United States.

Asian tiger mosquitoes prefer to lay eggs in containers, so the first thing the scientists decided to test was whether the size of the containers made any difference. They were also curious about whether or not the presence of flowers might affect the egg-laying behavior, due to the fact that mosquitoes drink flower nectar.

The researchers studied female mosquitoes that had been fed blood meals and released in large cages with water containers and flowering butterfly bushes (Buddleja davidii).

They found significantly more eggs in the largest containers, and they found more eggs in containers next to flowering bushes than in containers without flowers.

The researchers hope that these findings lead to new methods of controlling the mosquito.

“One of the potential outcomes of this study might be that someone could look at the flower fragrances as a way to lure egg-laying female mosquitoes to some sort of trap,” said Dr. Phil Kaufman, one of the researchers.

“This study provides evidence of the attractiveness of flowering butterfly bushes to ovipositing (i.e., egglaying) Aedes albopictus,” said Dr. Timothy Davis, another author. “Ovipositing mosquitoes are those that have taken a bloodmeal and, in instances where pathogen transmission is occurring, are the potential vectors as they may have acquired the pathogen through the blood meal. Therefore, exploiting the attractiveness of flowering butterfly bushes in developing control techniques could assist in stopping pathogen transmission.”

An Asian tiger mosquito (Aedes albopictus) feeding on the nectar of a flowering butterfly bush (Buddleja davidii).

Credit: Entomological Society of America

The researchers suggested that female mosquitoes lay eggs near flowers for a variety of reasons. Nectar is an important energy source, so pregnant females are obviously attracted to the flowers to feed themselves.

But it could also have something to do with providing food for the next generation in the form of nectar.

“Putting eggs in water near a nectar source may be a way of provisioning for the offspring, which do need sugar upon emergence,” said Dr. Kaufman.

The findings of this study may be used one day to increase the effectiveness of mosquito trapping and monitoring efforts, especially if the attractants from flowers can be isolated and replicated.

“Incorporation of phytochemicals that are produced by butterfly bushes may enhance ovitrap effectiveness, thereby improving surveillance and control efforts,” the researchers wrote.

MeV

For more information: Davis TJ, Kline DL, Kaufman PE. Aedes albopictus (Diptera: Culicidae) oviposition preference as influenced by container size and Buddleja davidii plants. Journal of Medical Entomology, January 2016 DOI: 10.1093/jme/tjv201 16

Issue 1/2016 | ModernEquineVet.com

CT proves useful in diagnosing conchal bullae disease bullae (average 15 cm3) and these were related to head size. In both dorsal and ventral bullae, there were significant differences in the volumes among different age groups (estimated by dentition), with the youngest group (0–5 years) having significantly smaller volumes than those in the oldest (>16 years).

In the case of the ventral conchal bullae, this could be explained by the larger size of cheek teeth alveoli protruding into the nasal cavity in younger horses.

The rostral limit of the dorsal conchal bulla was parallel to Triadan 07s in most horses (81.3%). The caudal limit was parallel to Triadan 10s in 61% and the 09s in 30.5%. The rostral limit of the ventral conchal bulla was parallel to Triadan 07s in 78% and the caudal limit parallel to the 09s in 64.5% and the 10s in 32%.

This anatomical information could help identify which structures are involved in sinus disease, they said.

MeV

Photo courtesy of The Equine Veterinary Journal

Computed tomography (CT) may prove to be a useful tool to diagnose sinus disease in horses, according to recent work from Edinburgh researchers.

Veterinarians are finding infections of the dorsal and ventral nasal conchal bullae, which are causing clinical signs of sinus disease but the anatomy of these two structures has not been well documented.

Diplomats examined CT images of 90 cadaver skulls. Specimens with dental or sinonasal disease (confirmed by skull sectioning and gross examination) were excluded from the study, leaving 60 specimens for investigation. Imaging software (OsiriX) was used to create multidimensional reconstructions and to measure height, length and width of dorsal and ventral bullae, allowing the volume of each bulla to be calculated. Height, length and width of each head also provided a volume for each skull.

The dorsal conchal bullae were found to be greater in volume (average 24 cm3) than ventral conchal

Left image: Ventral multiplanar reconstruction of a cadaver equine head at the level of 08 maxillary cheek tooth. Note white arrows indicating septae formation within the dorsal conchal bulla and ventral conchal bulla. Right: Transverse image of a cadaver equine head <4 years old. Note the small size of the left and right ventral conchal bullae (arrows) due to protrusion of the tall reserve crowns of the erupting 07 maxillary cheek teeth.

For more information: Liuti T, Reardon R, Smith S, Dixon PM. An anatomical study of the dorsal and ventral nasal conchal bullae in normal horses: Computed tomographic anatomical and morphometric findings. Equine Vet J. 2015 Oct 6. [Epub ahead of print]. http://www.ncbi.nlm.nih.gov/pubmed/26440763 ModernEquineVet.com | Issue 1/2016

17

news notes

Antibiotic prescribing habits can help or hinder resistance Antibiotic stewardship in both animal and human medicine is crucial to preserving the efficacy of lifesaving antibiotics, but under-dosing of antimicrobials or inappropriate prescribing are concerns among veterinarians.

U.K. researchers recommended that veterinarians perform a more accurate estimation of bodyweight to prevent further development of resistance.

They evaluated the selection of antimicrobials for traumatic limb wounds prior to referral to a single equine hospital. This was a good area to evaluate because the U.S. Department of Agriculture found that traumatic injuries or wounds were the most common reason for giving antibiotics to horses with 3.9% of those older than 6 months of age receiving antimicrobials for traumatic injuries in a 12-month period.

More than 96% of U.K. veterinary surgeons said that they too would prescribe antimicrobials for a contaminated limb wound, however, no one has investigated if that reflects actual practice, the researchers said.

They classified antibiotics according to the British Equine Veterinary Association (BEVA) guidelines as “first line,” “alternative,” “protected,” (e.g. third- or fourth-generation cephalospo-

rins and fluoroquinolones) or “inappropriate” (formulation is unsuitable for horses). At the referral center, dose rates were calculated using bodyweight measurements and if the dose administered was less than 90% of the reference dose, this was classed as under-dosing using reference doses according to BEVA guidelines.

Of the 113 cases included in the study, 94 (83%) had received antimicrobials prior to admission to the referral center and of these, 88% were given a firstline antimicrobial, 1% an alternative, 9% a protected antimicrobial and 2% an inappropriate choice. The most common drugs were gentamicin (65%), procaine penicillin (54%) and sodium benzyl penicillin (17%). Penicillin plus gentamicin was used in 56 cases. There was no association between use of protected antimicrobials and time since graduation, postgraduate qualifications or equine versus mixed practice. Although the number of horses receiving protected antimicrobials was low (n = 7), there was a significant relationship between use of protected antimicrobials and time since injury of more than 24 hours. The researchers argued that this is unlikely to be justified as first-line antibiotics combined with appropriate wound management are still effective in most chronic wounds.

For cases in which complete dosing information was available, 55% were under-dosed with at least one antimicrobial. For the penicillin and gentamicin combination, 25% of the 52 cases for which in-

To help prevent resistance, make sure bodyweight estimation is correct before prescribing

Pseudomonas aeruginosa Photo courtesy of Janice Haney Carr

antibiotics.

Staphylococcus aureus

Photo courtesy of Frank DeLeo, National Institute of Allergy and Infectious Diseases (NIAID)

18

Issue 1/2016 | ModernEquineVet.com

formation was available had been under-dosed with both drugs. Sodium penicillin was the drug most frequently under-dosed and by the greatest magnitude, with the median dose administered being only 56% of the recommended dose. There was no relationship between frequency of under-dosing and postgraduate qualification or type of practice; however, a significant relationship was found with time since graduation, with the odds of under-dosing increasing with years since graduation. Horses over 561 kg were more likely to be under-dosed than lighter horses. There was no relationship between under-dosing and breed.

“This study demonstrates the use of certain classes of antimicrobials in situations where typically they would not be considered necessary. If these findings reflect more general attitudes, then there is a need for

greater awareness of—and compliance with—recommendations for the controlled use of certain classes of antimicrobials,” the researchers wrote. “The study also provides concerning evidence of widespread under-dosing of antimicrobials in equine practice, even among experienced and equine-focused first-opinion practitioners. This situation could easily be rectified by the use of more objective estimates of horse weight, such as validated weigh tapes or portable weighbridges, which are now easily affordable for equine practices.”

MeV To help veterinarians ensure responsible use of antimicrobials, BEVA has a new program called Protect Me. Go to www.beva.org.uk/useful-info/Vets/Guidance/AMR.

For more information: Ross Se, Duz, M, Rendel DI. Antimicrobial selection and dosing in the treatment of wounds in the United Kingdom. Equine Vet J. 2015 Dec 25. doi: 10.1111/evj.12535. [Epub ahead of print] http://onlinelibrary.wiley.com/enhanced/doi/10.1111/evj.12535/

Boehringer Ingelheim strengthens position in animal health Boehringer Ingelheim and Sonofi have entered into exclusive negotiations to swap businesses. The proposed transaction would consist of an exchange of Merial, the Sanofi animal health business with most of the Boehringer Ingelheim consumer health care (CHC). The transaction would also include a gross cash payment from BI to Sanofi of $5.12 billion.

The animal health industry is an attractive industry in terms of innovation, growth potential and profitability, according to a press release from BI. Combining the two companies’ complementary strengths would create the second largest player in the global animal health market with pro forma sales of approximately $4.14 billion in 2015 with the ability to compete for global market leadership. The combined portfolios and technology platforms in antiparasitics, vaccines and pharmaceutical specialties would place the combined company in the key growth segments of the industry. The species portfolios are highly complementary, building on Merial’s expertise in companion animals and poultry and BI’s expertise in swine.

“Boehringer Ingelheim’s strategic priority is to focus on the company’s core areas of expertise and businesses with an established global scale, or where

a pathway to a global scale can be achieved and prioritized among Boehringer Ingelheim’s portfolio opportunities,” said Prof. Dr Andreas Barner, chairman of the Board, BI. “BI Animal Health is—and will stay—strongly committed to bringing novel, innovation-driven solutions to veterinarians and animal owners. Our combined Animal Health business would be well-positioned for growth and emergence as a leader globally. I am confident that Sanofi will enable our CHC business to fully live its potential supported by highly professional and committed teams.”

Lyon, France, the headquarters of Merial, would be a key operational center of BI’s Animal Health business. BI will commit to maintain business operations, R&D and Manufacturing Centers in France.

As the U.S. market is an important part of Merial’s business, BI would pay particular attention to sustain the momentum of the U.S. operations. the company said. BI will give particular attention to social matters as well as skills and retention sensitivities, the company said.

The execution of definitive agreements is expected in the coming months.

MeV ModernEquineVet.com | Issue 1/2016

19

The Modern

Equine Vet

Reach your veterinarians wherever they are, whenever they want.

FOR ADVERTISING RATES AND INFORMATION, EMAIL Matthew Todd