The role played by extrinsic nerves in colonic motor activity and motor coordination between the small intestine and the colon in the fasting state was investigated in a canine model. To evaluate motor activity before and after celiac and superior mesenteric ganglionectomy (CSMG), seven strain gauge force transducers were implanted in the small and large bowels of five dogs. No significant differences were observed in the frequency, duration, cycle, or migration time of bursts of contractions from the colon (BCC), or in the duration of the quiescent state before and after CSMG. When small intestinal phase III activity reached the ileocecal junction before and after CSMG, a characteristic contractile pattern, namely, small intestinal phase III activity followed by BCC, was observed at the ileocecal junction. Before and after CSMG, 84% and 83% of the small intestinal phase III activity, respectively, was transmitted to the colon as BCC after reaching the ileocecal junction. However, only 19% and 18% of BCC before and after CSMG, respectively, followed small intestinal phase III activity. These results led us to conclude that the extrinsic nerves exert little effect on fasting colonic motor activity and motor transmission from the small intestine to the colon.