Abomasal dilatation and emptying defect in a ewe.

On the basis of chronic weight loss, bilateral asymmetric abdominal distention, ballottement of a large abomasum, hypochloremic metabolic alkalosis, and high rumen chloride concentration, an adult Suffolk ewe was diagnosed as having an abomasal emptying defect. In this ewe, and in 4 of 7 other sheep diagnosed as having abomasal emptying defects, aspartate transaminase and sorbitol dehydrogenase activities were high, and histopathologic evidence of hepatic congestion and ischemia was found. It was theorized that increased intra-abdominal pressure from abomasal distention may be the cause of the hepatic abnormalities. These changes have not been previously associated with ovine abomasal emptying defect, the pathogenic mechanism of which remains unclear.