A 90% small bowel resection in 8 dogs resulted in a significant decrease (p < 0.05) in D-xylose and D-glucose absorption during the early postoperative period. The absorptive capacity of the residual gut with regard to L-alanine, however, remained unchanged. Anemia and hypoalbuminemia also occurred in time, suggesting a malabsorptive state. Control studies were performed in 8 dogs with small bowel transections. The results suggest that a high protein diet might be of benefit during the early postoperative period after massive small bowel resection.