Segmental atresia of the transverse colon in a foal with concurrent equine herpes virus-1 infection.

Segmental atresia of the transverse colon was observed at necropsy in a neonatal foal. The dorsal and ventral components of the large colon were fused, and ended blindly. The small colon was collapsed and completely closed at its cranial end. The right and left dorsal and ventral colons were fused into one blind-ended tube. Histologically, eosinophilic intranuclear inclusion bodies demonstrative of Equine Rhinopneumonitis were present in the thymus.