Gastric ulceration is a common cause of poor performance in horses. An estimated 60% of sport horses suffer from this condition, and suffer is the right word as ulcers cause chronic debilitating pain.

Humans who have experienced gastric ulcers will recognise how painful they are and how they might affect performance in an athlete. Stress, high intensity training and nutritional practices (intermittent feeding of high sugar, low roughage feeds) are recognised factors that contribute to gastric ulcers in adult horses.