b'2019 AAEP CONVENTION WRAP-UPlow, but theyre not going to treat the disease, Andrews said. INFECTIOUS DISEASE Influenza Cases on the RiseLow-starch diets In one study out of the U.K., researchers compared ulcerEquine influenza virus (EIV) cases have increased over the past decade, with some years recurrence in two groups of horses onworse than others. Plus, the demographics of affected horses are changing, and more horses omeprazole: one consuming a low-starchvaccinated against the disease are becoming infected. diet and one a normal diet. Reuss saidTo gain a better understanding of EIVs current prevalence and patterns, Wendy Vaala, VMD, the low-starch group experienced fewerDipl. ACVIM, director of life-cycle management equine and companion animal at Merck Ani-recurring ulcers than those on normalmal Health, and a team of colleagues and researchers from the University of California, Davis, diets, whose ulcers recurred within alooked at EIV cases identified through Mercks voluntary biosurveillance study over 11 years.month. The team reviewed data from 239 clinics in 38 states from March 2008 to February 2019. The bottom line Andrews take-homeThe study included 7,809 horses showing respiratory signs and fever. Upon testing their nasal messages for attendees included: swabs using qPCR, which looks for DNA, 9.2% (718 horses) tested positive for EIV, with the 1.Omeprazole is still the mainstay treat- number of cases per year increasing throughout the study period. ment for both ESGD and EGGD. Vaala said equine herpesvirus-4 (EHV-4) is usually the most common respiratory patho-2.Equine glandular gastric disease usu- gen identified in horses displaying these signs. When the incidence of EIV overtakes EHV-4, ally requires multiple therapies, includ- we know its going to be an unusually active year for EIV in general, she said, adding that ing omeprazole with sucralfate and/or2013 marked the first year EIV outranked EHV-4. misoprostol. In the study, Vaalas team found a higher-than-expected percentage of EIV positives in 3.Diet is important for preventing diseasehorses ages 1 through 9. Its no longer a young horse condition, she said. Quarter Horsesrecurrence, especially ESGD; low-carband horses that had recently been transported were also overrepresented.(sugar) approaches are useful. Forty-one percent of infected horses were competition horses, while 37.9% were pleasure 4.To maximize treatment effectiveness,horses, which Vaala said indicates staying home doesnt protect you from influenza. Sixty-one percent were current on vaccination against the virus, meaning vaccination is not always give omeprazole first thing in theprotective. This could be due to antigenic drift or shiftminor and major changes, respectively, morning, followed by a hay meal 60to the viral genes over time. Further, there are various types of EIV vaccines, and not all are minutes later. the same.5.Supplements might improve or main- Equine influenza virus is always changing (drifting), and the strains of EIV in the vaccine tain stomach health but are not effica- may affect the level of protection provided, Vaala explained. It is not just a question of if the cious in treating gastric ulcers. horse has been vaccinated, but did the vaccine used contain EIV strains that provided suf-6.Other omeprazole formulations mightficient cross-protection against the flu strains circulating?become available in the future, whichTo combat this challenge, researchers are constantly monitoring currently circulating stains could improve treatment success. of EIV and comparing them to the strains of flu in currently available vaccine products.While much of the session focused onMost cases occurred in winter and spring. There is an equine flu season, said Vaala, gastric ulcer treatment and prevention,from mid-winter to early spring. This might impact when you choose to vaccinate against EIV. in closing Reuss emphasized the impor- The AAEP vaccination guidelines recommend veterinarians vaccinate at-risk horses (e.g., tance of getting an accurate ESGD orperformance and recreational horses) twice a year. Ideally, horses at increased risk for EIV EGGD diagnosis. should receive a booster vaccination prior to peak exposure, which suggests late fall and late Horses always need to be scoped tospring might be ideal times for booster vaccinations, said Vaala.first provide an accurate diagnosis andIn summary, she said, owners and veterinarians should be aware that EIV prevalence is on then subsequently to monitor responsethe rise, with adult horses at greatest risk in late winter and early spring. to treatment, she said. Without seeingDiscuss vaccination with your veterinarian, she added. The vaccine used and the timing before and after pictures, we cannot pos- both play a role in efficacy.Alexandra Beckstettsibly know what treatments are actually working.Alexandra BeckstettPostoperative reflux can indicate stasismore intense management following Old Horses Arent at Higher Risk of(lack of movement) of the intestinal tract,surgery, and Reflux Post-Colic Surgerymechanical obstruction at an anastomo- 2.Help owners prepare for this expensive, Various complications can develop fol- sis (where intestines have been joinedpotentially fatal complication. lowing colic surgery, some more conse- together after a resection during colicThe perception that older horses have quential than others. While veterinarianssurgery) or adhesion site, or even an in- more complications after colic surgery can treat incisional infections or low- testinal repair breakdown, said surgicalis widespread and extends to postopera-grade fevers with antibiotics, persistentresident Sophie Boorman, BVetMed, oftive reflux, said Boorman. This is likely postoperative gastric reflux (POR, fluidAuburn Universitys College of Veterinarybecause older horses tend to develop accumulation in the stomach) is a moreMedicine.strangulating lipomasa benign fatty serious problem thats more difficult toShe said predicting which horses havetumor that can entrap and strangulate the resolve. And, as a multi-institution re- a higher risk of developing postoperativesmall intestine, causing bowel devitaliza-search team recently found out, POR cangastric reflux might:tion and necessitating surgery. prove more deadly to its victims.1.Help identify horses that will needHorses colicking because of small 44March 2020The Horse|TheHorse.comAAEPWrapUp.indd 44 2/5/20 2:54 PM'