Two Swiss Braunvieh cows in late pregnancy underwent surgery because of a r
are form of ileus due to strangulation of the duodenum at its caudal flexur
e by the gravid uterus. The whole uterus had passed through a gap between t
he mesoduodenum and duodenum and with increasing weight had led to strangul
ation of the duodenum. This was possible since the mesoduodenum and both wa
lls of the greater omentum adjacent to its caudal edge were not connected w
ith the duodenum, probably due to a congenital inhibitory malformation. A t
ranssection and an end-to-end anastomosis of the duodenum were necessary in
both cases since it was impossible to retract the gravid uterus through th
e defect. Postoperative recovering was uneventful in both cows, which were
discharged after seven and five days respectively and calved normally about
two months later. (C) 2001 Harcourt Publishers Ltd.