Intramural hematoma in the jejunum of a mare.

An intramural hematoma involving a 40-cm segment of the distal portion of the jejunum caused intestinal obstruction and colic in a mature mare. The involved intestine was resected, and an end-to-end anastomosis was performed. The mare recovered completely, but 4 years later had colic caused by incarceration and volvulus of the distal portion of the jejunum, involving fibrous abdominal adhesions. The cause of hematoma was not identified; however, rupture of an intramural vessel after migration of Strongylus vulgaris larvae was considered a possibility because of the histologic observation of an intense eosinophilic infiltrate in the region. Vascular rupture caused by blunt abdominal trauma was considered unlikely. Previous descriptions of intramural hematoma in the horse have been confined to the small colon.