Stomach Ulcers: A Threat to Horses of All Ages

Megan Green, DVM, manager of Merial Large Animal Veterinary Services, responds to a question about equine stomach ulcers.

Q. I have several young horses in my care that aren’t in training yet. Is it possible for them to get equine stomach ulcers?

A. You’re smart to ask that question. We often think our young horses are immune to equine stomach ulcers because they aren’t exposed to the stressors that we know can contribute to ulcer development. Those stressors are more often associated with the kinds of activities we do with actively competing horses such as training, traveling, and trailering.

Unfortunately, even though young horses generally aren’t exposed to stressful activities, they can develop stomach ulcers. In fact, the presence of ulcers in foals has been reported as ranging between 25% and 51%.

Part of what contributes to the development of ulcers in such young horses is the functioning of the stomach itself. A horse’s stomach secretes acid 24 hours a day, seven days a week. Foals have been documented to secrete gastric acid as early as two days of age. When the acid builds up in the stomach, it can lead to the development of ulcers, regardless of the foal’s or adult horse’s age.

Diagnosing ulcers in a horse or foal can be done conclusively with the use of an endoscope. However, a presumptive diagnosis can also be made based on clinical signs, which can include teeth-grinding, salivation, interrupted nursing, and colic. However, these signs have only been observed in a minority of foals.

Besides the build-up of acid possibly leading to ulcers, all foals undergo the stressful process of weaning, usually between four and six months of age. That stress can contribute to the formation of ulcers.

Should you suspect your foal or young horse has ulcers, consult a veterinarian. He or she will determine, based on the clinical signs, what course of action to recommend. For the treatment of ulcers in foals over four weeks of age, your veterinarian might prescribe GastroGard. The active ingredient, omeprazole, works to suppress acid secretion. To prevent ulcers from developing during time of stress, talk to your veterinarian about the possibility of using omeprazole (marketed as UlcerGard) on horses that weigh at least 600 pounds.

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