Jejunal obstruction caused by a Pythium insidiosum granuloma in a mare.

An 8-year-old Missouri Fox Trotter mare was examined because of intermittent, low-grade abdominal pain and weight loss for 3 months. Incomplete jejunal obstruction, caused by a granulomatous mass in the wall of the jejunum, was identified during exploratory celiotomy. Pythium insidiosum was identified as the cause of the granuloma. This case suggests that enteric pythiosis may develop in horses that are geographically distant from the Gulf Coast.