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3-Meter Video Endoscope
We routinely utilize our gastroscope.  The endoscope is long enough to reach into an adult horse’s stomach and the first section of small intestines (the duodenum). This equipment gives us the capability of definitively diagnosing stomach ulcers in horses.

Stomach ulcers are very common in horses in training. Observational studies have shown that up to 90% of horses in training, regardless of breed and type of exercise, may have ulcers of varying severity. Also, the clinical signs shown by horses may not be proportional to the severity of the lesion. The clinical signs are also not always colic type signs, but instead they may be signs such as a poor attitude, poor appetite, poor quality hair coat, or poor performance.

According to Dr. Merritt at the University of Florida, the upper part of the stomach is usually not in contact with ingested food material and especially not in contact with stomach acid. The contraction of abdominal muscles, which occurs during exercise, causes an increase in the intra-abdominal pressure. The increased pressure pushes the acidic stomach content up into the upper part of the horse’s stomach. Repeated exposure to the acid results in ulcers in that portion of the stomach.

Horses at rest in pasture do not experience the increased abdominal pressure of horses at exercise. So, we can understand the association of training with ulcers is not stress related but rather mechanical in nature. We also can understand the importance of checking for ulcers anf treating for ulcers if present.


The image above shows multiple ulcers in the non-glandular part of a horse’s stomach. These ulcers bled and show dark red discoloration at each location.