Preventing Ulcers Is A Matter Of Timing
Antibody tests help practitioners diagnose gastrointestinal health conditions in equine patients.
Photos Courtesy of ULCERGARD (omeprazole) and Michael J. Murray, DVM, MS, Dipl. ACVIM
Succeed Equine Fecal Blood Test, which was taken off the market early this year because of manufacturing difficulties, will be relaunched this month. The new antibody test helps practitioners diagnose gastrointestinal health conditions in equine patients.
Freedom Health LLC voluntarily stopped making the product because of inconsistencies in the delivery method for results. Changes have been made in manufacturing the test strips, which previously did not wick up the solution and activate properly.
“The science used in the test is accurate and highly reliable,” said Patrick Warzcak, Freedom Health’s vice president of marketing. “The use of novel antibodies to detect specific components of equine blood in feces as an indication of GI tract conditions is supported by several studies and our own testing.”
The kit consists of Test A to detect albumin and Test H to indicate the presence of hemoglobin. Together, they can help differentiate foregut from hindgut conditions, the company says.
The test can be performed in the barn in a few minutes with only a fecal sample, 3 ounces of clean tap water and a single kit. Results appear within five minutes.
‘My horse isn’t nervous. How can it have an ulcer?”
Horse owners often pose that question to veterinarians, says James Christensen, DVM, of East Valley Equine Practitioners in Mesa, Ariz.
Dr. Christensen, who operates a mobile equine practice, says horse owners need to understand that many backyard horses have ulcers.
“Ulcers cause a vast range of problems—bad behavior, irritability, loss of performance, poor coat, weight loss and recurrent colic,” he says.
The key to staving off equine ulcers, Christensen says, is frequent feeding, which ensures that horses have adequate long-stem forage in their stomachs most of the day to keep the pH level acceptable.
“We’ve domesticated these animals,” he says. “We only feed them twice a day, which generally includes grains or pelleted feed. So due to this, horses can’t buffer the acid levels in their stomachs, which then leads to chronic gastric irritation.”
Lutz Goehring, DVM, MS, Ph.D., Dipl. ACVIM, says many racehorses develop stomach ulcers because of a low-fiber, high-grain diet.
“Fiber from hay or grass builds a barrier in the stomach which keeps acid in the lower but better protected part of the stomach,” says Dr. Goehring, assistant professor of equine medicine at James L. Voss Veterinary Teaching Hospital at Colorado State University.
Performance horses don’t always get reasonable amounts of roughage because they are traveling or in competition. Often they are fed irregularly. Gastric acid is manufactured in the stomach continuously, even when horses don’t eat, Goehring says. Without roughage, this amount of acid is not buffered or neutralized.
Adult horses develop ulcers more often in the front of the stomach. Foals are more likely to get ulcers in the front and back of the stomach. The back of the stomach is covered with a thick, protective mucus layer. This barrier can break down when a foal gets sick or is treated with non-steroidals such as phenylbutazone.
Whenever stomach emptying is delayed, food and acid are not transported properly into the small intestine, where the acid mixes and neutralizes. Colic, and in particular any disease of the large colon, or hind gut, decreases gastric emptying.
The only way to truly diagnose equine gastric ulcer syndrome is to use an endoscope to peer inside the stomach, Goehring says. A 3.5-meter endoscope passed down the esophagus allows practitioners to see both areas of the stomach.
Studies and experience have shown Goehring that it is not an uncomfortable procedure for the horse, unlike stomach endoscopy in humans. It’s still a good idea to sedate the horse and put it in stocks in case the horse resents the procedure.
Studies have shown, he says, that horses can develop ulcers during the 12 hours they fast before a scope, mainly because their stomachs are still producing gastric acid. However, lesions should be minimal.
“Depending on the grade of the disease, there could be minor ulcerations and erosions along the margo, which are starting to bleed,” Goehring says. A grade of zero means normal, 1 is for tiny, superficial erosions, and 2 and 3 are much more severe.
“In our mobile practice we used to not look for ulcers due to the lack of quality portable video endoscopy equipment,” Christensen says.
“The majority of the specialty hospitals now have video endoscopes. We’ve just acquired one and our ability to diagnose and treat horses is vastly improved.
“We are not just treating symptoms and we are no longer guessing what the problem is,” he says. “We see it right on the screen.
Seeing Is Believing
“Clients love seeing what the doctor is seeing,” he says. “It helps them visualize the source of the problem and makes it an interactive learning experience for horse owners.”
In today’s economy, Christensen says, some owners want the ulcer treated in a cost-effective way first. That means using sucralfate, ranitidine or cimetidine to try to solve the problem before moving on to video endoscopy and anti-ulcer drugs such as omeprazole.
For an adult horse with a grade 3 ulcer, both Christensen and Goehring suggest that practitioners begin aggressive treatment to block acid production. A grade 1 or 2 ulcer can make a horse uncomfortable enough to stop eating, and these ulcers need to be treated, too.
“With the introduction of the gastric acid pump-inhibitor omeprazole, we can increase the pH in the stomach and promote healing,” Christensen said.
Sucralfate, ranitidine and cimetidine are administered three times a day, Christensen said. He finds them less effective in healing gastric ulcers than omeprazole, now marketed in two strengths as Merial’s GastroGard and UlcerGard.
In regular transport, motility pushes food and acid into the small intestine, where the acid mixes and neutralizes. If the horse gets distracted or stressed, the movement is slowed. Colic results when GI motility and stomach emptying time are disrupted.
Goehring and Christensen agree the best treatment after scoping and verifying that the stomach is ulcerated is to use omeprazole, which inhibits and buffers gastric acid production, allowing tissue to heal and restoring the integrity of the stomach wall.
Christensen says about 80 to 90 percent of the ulcers heal satisfactorily. He recommends that owners continue administering a decreased dose of omeprazole to minimize recurrence.
If horses will be traveling or performing in shows or speed events, Goehring suggests strict adherence to a feed schedule and that the horses get regular exposure to hay or forage. An anti-ulcer medication can help, too, to prevent them from “going into a downward spiral and not eating,” Goehring says.
Glandular lesions from overdoses of non-steroidal anti-inflammatory drugs, including flunixin meglumine and phenylbutazone, may create ulcers in the back of the stomach and large intestine.
“If the correct dosage of non-steroidals is managed, horses are typically safe,” Goehring says.
Omeprazole has no influence on large intestine or colonic ulcers, Goehring and Christensen agree.
Sucralfate will help coat the ulcerated areas in the stomach and the small intestine but won’t work on ulcers in the large intestine, Goehring says.
Frank Hurtig, DVM, MBA, director of Large Animal Veterinary Services at Merial, held scoping events in 2007 at the University of Pennsylvania’s New Bolton Center and at Colorado State University to promote understanding of equine gastric ulcer syndrome.
Twenty-six horses, ranging from Thoroughbreds to Quarter Horses and used for dressage, eventing and trail riding, were scoped. Only four showed no sign of ulcers.
Dr. Hurtig says the owners and veterinarians provided excellent care of the horses during his visits, yet the animals still experienced equine gastric ulcer syndrome.
“This follows earlier findings that EGUS can develop in horses exposed to stress in as little as five days,” Hurtig says.