Today's Horse - Ask the horse expert: Stomach Ulcers in Foals

Stomach Ulcers in Foals
Dr. Jennifer MacLeay is an author and lecturer who is currently based in Fort Collins, Colorado. Dr. MacLeay was born and grew up in Northern New Jersey. Her interest in horses began early and she participated in hunt seat equitation and eventing for many years. Dr. MacLeay has a Bachelor of Science degree from the University of New Hampshire and received her Doctor of Veterinary Medicine from the Ohio State University.
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Question
I just had a friend lose a foal to peritonitis caused by a ruptured stomach ulcer. The foal was a month old, and appeared healthy until just before it died. Last year I had a month old foal get colic, attributed by the UGA Vet school to the same problem.

How do we diagnose ulcers in young horses? Why do some foal get them? What can we do to help avoid them?

Barbara Bendzunas

Answer
Dear Barbara, This is an excellent and timely question for this time of year. Stomach and, to a lesser extent, intestinal ulcers are a big problem in both adult horses and foals. While we do not know everything there is to know about why horses get ulcers we know much more than we used to.

First we should talk about the horse's stomach. The horse's stomach is similar to ours except there are two regions. One region is coated with a thicker type of lining than the other, which is largely lined with glandular cells. This glandular portion is most similar to our own stomach. The stomach lining produces both acid and mucus. The mucus protects the lining cells from being damaged by the acid which is necessary to help digest food. Horses produce small amounts of acid all of the time compared to other species which produce acid primarily when they eat. This makes sense when we consider that horses are "designed" to eat most of time since they are grazing animals. Similarly, foals nurse small amounts throughout the day.

Stress increases the amount of acid being produced in the stomach. In addition, certain commonly used anti-inflammatory medications (NSAIDs) such as phenylbutazone ("bute"), banamine or ketofen may decrease the amount of mucus produced in the stomach. Stress or NSAIDs alone or in combination set up a situation where stomach ulcers may develop. In adult horses, feeding diets rich in grain compared to hay have also been implicated.

In foals, some small ulcers in the stomach appear to be normal in the first week of life. These ulcers appear to be a normal developmental process in foals and do not cause disease. But, some foals do develop severe ulcers. The foals that most often get ulcers are those that have an underlying disease such as pneumonia, diarrhea or angular limb deformity. Other times the foal may have been moved around a lot with it's mare as she is sent to other farms to be bred. More rarely, we do not have a specific reason why the foal has developed a clinically relevant ulcer and it is the ulcer itself that is the primary problem.

Ulcers can be treated by 1) treating the underlying disease and 2) placing the foal on anti-ulcer medications. The main ones we use are cimetidine and ranitidine and omeprazole. All 3 work well but cimetidine and ranitidine work in a slightly different way than omeprazole. Foals in our hospital that are being treated for other problems are typically placed on anti-ulcer medications as a preventative long before we suspect they have an ulcer.

At the farm, common use of anti-ulcer medications is probably not indicated unless the foal is under stress from a disease such as pneumonia, diarrhea or is stall bound due to angular limb deformities, joint contraction, joint laxity or some other problem. It is always a good idea to discuss with your veterinarian whether anti-ulcer medications are indicated whenever you are concerned about a foal's stress level.

Complications related to ulcers in foals are not uncommon and include from the most mild symptoms such as ill-thrift and poor appetite to colic, rupture of the stomach and peritonitis (bacterial infection of the abdominal cavity), pyloric obstruction due to scarring (stomach cannot empty normally), aspiration pneumonia or mega-esophagus. The earlier any of these complications are treated the more likely it will be that the foal may survive.

While some anti-ulcer medications are expensive, their cost pales in comparison to hospitalization for any of the complications I listed above or the death of the foal. Therefore, you should consult with your attending veterinarian about whether a foal should be placed on an anti-ulcer medication. I would not recommend treating any and all foals simply to "cover your bases" as no medication is without some side effects.

Thanks for your question, I am sure it was one shared by many of your fellow Todayshorse.com readers.

Question I just had a friend lose a foal to peritonitis caused by a ruptured stomach ulcer. The foal was a month old, and appeared healthy until just before it died. Last year I had a month old foal get colic, attributed by the UGA Vet school to the same problem.

How do we diagnose ulcers in young horses? Why do some foal get them? What can we do to help avoid them?

Barbara Bendzunas

Answer Dear Barbara, This is an excellent and timely question for this time of year. Stomach and, to a lesser extent, intestinal ulcers are a big problem in both adult horses and foals. While we do not know everything there is to know about why horses get ulcers we know much more than we used to.

Question
I just had a friend lose a foal to peritonitis caused by a ruptured stomach ulcer. The foal was a month old, and appeared healthy until just before it died. Last year I had a month old foal get colic, attributed by the UGA Vet school to the same problem.

Answer
Dear Barbara, This is an excellent and timely question for this time of year. Stomach and, to a lesser extent, intestinal ulcers are a big problem in both adult horses and foals. While we do not know everything there is to know about why horses get ulcers we know much more than we used to.