Endoscopy: Looking in Dark Places
ULCER SYNDROMES IN THE DIGESTIVE SYSTEM OF HORSES
An average sized horse has around a hundred feet of length in its digestive system starting with the lips and ending at the anus. Inside the horse, the stomach, small intestine and the large intestine (colon) make up most of this total length.
With the advent of three-meter long video-endoscopes, we have the ability to explore the entire stomach and first part of the small intestine. There is no means available to explore the inside of the small intestine or colon in the living horse.
There is still much to be learned about ulcer syndromes in horses. We are getting a much better handle on stomach ulcerations, now that most equine practices have three-meter scopes, however, the incidence, severity, and significance of hind-gut colonic ulceration are not well understood due to the physical inaccessibility of this area.
So what might make you suspicious that your horse might have ulcers? Signs can be vague for sure but some things that we see in horses with stomach ulcers might include: decreased appetite, behavioral changes, poor performance, weight loss, mild colic especially after eating, mood changes relating to abdominal discomfort, and other non-specific signs.
Symptoms of hindgut ulcer disease can be even more vague but can include any of the above. Since the hindgut is responsible for fermentation of feed, and water reabsorption from ingesta, abnormalities in the hindgut may lead to wet soft manure. Severe cases may lose protein through the gut wall.
What causes these ulcer diseases? These are likely largely manmade diseases. Horses are meant to live in large areas, with their friends and families eating low-calorie roughage for 15-20 hours each day and covering many miles to do so. They have evolved to have small amounts of food moving through the gut almost constantly. That is nowhere close to the reality for our horses in captivity. We know that things like stress, batch feeding, and feeding low roughage/high-calorie feeds can predispose horses to stomach ulcers. There may also be as genetic predisposition as with many conditions. The most common cause of significant hindgut ulcer disease is chronic or acute overexposure to non-steroidal anti-inflammatory drugs like phenylbutazone, flunixin, etc.
Diagnosis of stomach ulcers can only be done by scoping the stomach. Hindgut ulcers are more difficult, but sometimes blood work may give us some clues. There is a lab test that uses a manure sample to look for hidden blood products but clever university people who study ulcer disease in horses find it to be inaccurate and do not use it. We do not either.
Treatment of ulcer diseases starts with trying to feed and manage horses in a natural way with good quality hay or pasture, minimizing processed high-calorie foods and minimizing stressors. For most stomach ulcers along with the changes above, we treat the horse with a drug called OMEPRAZOLE.
The trade name for this drug is GASTROGUARD. Unfortunately, this drug needs to be given daily during the treatment period and is pretty pricy, but has been proven again and again in good studies that it is the only one that works. It is a proton pump inhibitor that changes the acid level in the stomach and allows the ulcers to heal. Because it is not cheap, some people try to get by with compounded generic omeprazole which just does not work. Gastroguard has a patented formulation that allows it pass through the empty stomach into the small intestine where it is absorbed and then has an effect on the proton pump in the stomach. We have horses come in for scoping that have been on generic omeprazole that still have large non-healing stomach ulcers.
Hindgut ulcers, if suspected, are managed by stopping any medications and providing proper nutrition. A drug called SULCRAFATE has been used with disappointing results.
Prevention is best achieved by proper feeding and good management, however, sometimes all these goals cannot be met. Low dose GASTROGUARD can be useful to prevent ulcer formation during times of stress and lots of competition horse do very well on a half or even a quarter tube of Gastroguard during times of stress.