SummaryIn two groups of 20 cats each, the healing processes in resected and anastomosed bowel after use of a stainless steel surgical knife and an electric knife were studied. The animals were sacrificed after 24 and 48 hours, and four, six and 11 days. The anastomoses were resected and specimens were examined. Histologic study of specimens of tissue from Group I (stainless steel surgical knife) on the fourth and sixth postoperative days revealed proliferation of fibroblasts, granulation tissue, epithelial healing, and fusion of the opposed aspects of the muscularis. The healing process in Group II (electric knife) was characterized by necrosis of tissue, exudate of fibrin and leukocytes, and incomplete fusion of the opposed muscularis. Histologic studies showed a lag in total tissue repair of two days in Group II. These results suggest that the stainless steel knife is preferable for colonic surgery.