Gastric Ulcers in Horses

Gastric ulcers in horses are far more common than many people realize. The condition is very often found in horses kept in stalls frequently trailered or undergoing intensive training. The associated anxiety in addition to artificial and controlled feeding routines alien to a horses natural grazing patterns may put the animal under varying levels of stress.
According to Prof. Jorge Nieto with Surgical and Radiological Sciences University of California Davis gastric ulcers can affect any horse at any age. In adult horses gastric ulcers occur more frequently in animals that perform athletic activities with the highest frequency found in Thoroughbred racehorses 80 to 90 percent followed by endurance horses 70 percent and show horses 60 percent.

Researchers have found that exercise increases gastric acid production and decreases blood flow to the gastrointestinal GI tract. During exercise the fluid in the lower segment of the stomach where gastric acid is secreted splashes and exposes the more vulnerable upper segment of the stomach to an acidic pH.
But to better understand gastric ulcers it is first necessary to understand the workings of the horses stomach. 
A horse has a small stomach compared to its size and in fact compared to the size of stomachs of a number of other species. It holds only about four gallons of food. This is because horses evolved to graze and move constantly. As prey animals their flight instinct means they are always be ready to move to safer ground in the face of danger. It has served them well to be able to thrive on small snacklike meals processed by a small stomach that under optimum conditions was seldom empty.
Those eating habits did not disappear with domestication. The need for frequent small meals is just as important today in a controlled stall or paddock environment as it was when they were wild. In fact horses in the wild today do not get ulcers. Unfortunately it is the diet and lifestyle we have placed on horses that has brought about this painful and disabling condition. The good news though is that gastric ulcers are both curable and preventable with adjustments in feed a feeding routine that matches their physiological needs and measures to reduce the horses stress and anxiety.
The horses stomach is divided into two distinct regions the squamous region at the top considered a continuation of the esophagus lining and the glandular mucosa at the bottom similar to the