The patient is a 12-year-old Arabian gelding used for endurance riding. The clinic was called as the horse was not eating well and started to show signs of abdominal discomfort, such as stretching out and acting like he had to urinate,
The patient is a 12-year-old Arabian gelding used for endurance riding. The clinic was called as the horse was not eating well and started to show signs of abdominal discomfort, such as stretching out and acting like he had to urinate, without actually urinating. Upon physical examination, Dr. Crawford determined that the horse was indeed suffering from a very mild bout of colic, but no clear reason was evident at this time.
Since the signs of colic were mild and intermittent, a gastroscope was scheduled. Gastroscopy involves sending a thin fiber optic camera through the nasal passages into the stomach to visualize the lining of the stomach and beginning of the small intestine.
Gastroscopy revealed severe gastric ulcers (erosions of the normal tissue) in both the upper and lower parts of the stomach.
Gastric ulcers have been estimated to be present in 60-90% of adult horses, depending on age and job. Ulcers are also found in 25-50% of foals. In order to understand ulcers, a basic understanding of equine anatomy and physiology is warranted.
The horse stomach is divided into two distinct regions, the esophageal (non-glandular) region and the glandular region. The esophageal region, or squamous mucosa, covers approximately one-third of the equine stomach and has no glands or secretions. The glandular region covers the remaining two-thirds of the stomach and contains glands that secrete hydrochloric acid, pepsin, bicarbonate, and mucus. The two regions are separated by a very distinct line called the margo plicatus.
The equine stomach continuously secretes variable amounts of hydrochloric acid throughout the day, and secretion of acid occurs without the presence of feed material. Horses are designed to be grazers, therefore always having something in their stomach to help buffer the acid. The stomach secretes approximately 1.5 liters of gastric juice hourly, so if the stomach is empty of feed material the acid is