To study the movement of dog colon, bipolor electrodes and strain gauges were attached to the four different portions, ascending, transverse, descending and sigmoid colons.
Myoelectrical activities and mechanical activities were recorded simultaneously in the conscious state for one month.
Slow waves were recorded more clearly in the proximal colon than in the distal colon.
The frequencies of the slow waves were 5-6 cycles/min and were not altered by intravenous administration of motor stimulant agents. A spike activity complex was recorded more frequently in the distal colon than in the proximal colon. The spike activity complex usually appeared when contraction movement of the colon was active. The incidence of spike activity complex was mostly high in the descending colon. Contractile activity appeared once every minute with spike activity complex lasting for 10-30minutes.
On a low residual meal, mechanical activity and spike activity complex propagated from ascending colon to rectum were observed more distinctly than on usual dog food.