Effects of extensive resection of the small intestine in the pony

Abstract

SUMMARY Small intestinal resection ( sir ) is not uncommonly done in surgical treatment of equine colic, but little is known about the long-term effects of sir on horses and ponies. Twelve ponies, fed maintenance amounts of pelleted feed, were divided randomly into 4 treatment groups. d -Xylose absorption curves were recorded for each pony before surgical treatments were performed. Treatments consisted of control (ileal bypass) and 40%, 60%, or 80% sir . d -Xylose absorption, serum electrolyte, and enzyme profiles for each animal were recorded once every 30 days for 180 days after surgical treatment, and the ponies were weighed every 2 weeks. The ponies then were necropsied and the remaining small and large intestine were examined. d -Xylose absorption values were depressed ( P < 0.05) in the ponies subjected to 40%, 60%, and 80% sir as compared with the absorption values of the controls. The ponies with the 60% and 80% sir lost body weight throughout the experimental period, whereas the controls and the ponies with 40% sir maintained their base-line (presurgical manipulation) weight. Serum alkaline phosphatase activity was increased ( P < 0.05) in the ponies subjected to 60% and 80% sir and significant biliary hyperplasia was present in those with 80% sir . Extensive (≥ 60%) sir severely compromised the capability of ponies to absorb nutrients and to derive adequate nutrition from a maintenance diet, resulting in changes in hepatic parenchyma and elevations in serum alkaline phosphatase. These changes are consistent with those reported in other species following sir .