Congenital diaphragmatic eventration in a stillborn foal.

A stillborn full term foal was presented at necropsy. The dilated duodenum and the dorsal and ventral left colon and cecum extended into the thoracic cavity and were encased by a thin transparent membrane originating from the diaphragm. The congenital condition was diagnosed as a developmental anomaly with diaphragmatic eventration. To the authors' knowledge, this is the first report of diaphragmatic eventration in a Thoroughbred stillborn foal.