Idiopathic perforating ulceration of the small intestine in five adult horses

Perforating ulceration of the small intestine was diagnosed in 5 adult horses. Affected horses presented with signs of low‐grade colic, depression and inappetance. Abdominal paracentesis yielded abnormal peritoneal fluid in all cases. Perforating ulcers were located at the mesenteric border in 4 horses and the ileum in one horse. All horses had diffuse septic peritonitis. The aetiology of the condition is unknown.