Signalment:23-year-old Quarter horse gelding
History:Oone-month history of unresolving chronic diarrhea.
Gross Lesions:The serosa of the large intestine and the cecum were covered in hundreds of dark black slightly raised variably sized plaques ranging from 0.3 cm to 2cm. The large intestinal mucosa was thickened, edematous, dark brown to black and with ten to twenty polypoid semi-firm proliferations predominantly in the cecum. The large intestinal lesions were least severe in the right dorsal colon.