The vagus nerve was examined electromyographically for effect on the abomasal movement in adult female goats subjected to dorsal or truncal vagotomy. The results obtained are summarized as follows.
1. After dorsal vagotomy, the discharge interval prolonged slightly and the propagation velocity decreased.
2. After truncal vagotomy, the propagation velocity did not show a remarkable change except that the discharge interval showed a tendency to prolong slightly.
3. Neither dysrhythmia nor antiperistaltic discharge was seen after dorsal or truncal vagotomy.
4. The movement of the reticulum showed a tendency to be affected with temperature after dorsal vagotomy. It was not recorded after truncal vagotomy. The goats vagotomized dorsally showed an increase in body weight and decrease in volume of feces accompanied with repeated bloat. The goats vagotomized truncally died of acute frothy bloat 2-10 days after operation.
Therefore, it was suggested that truncal vagotomy might have exerted a greater effection all the stomach of the ruminant than dorsal vagotomy, which reduced the movement of rumen more remarkably than the movement of the abomasum.

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In order to clarify the propagation mechanism of canine gastric electrical activity, the stomach was transected and reanastomosed at the middle antrum in 3 dogs and at the distal corpus in 3 dogs.
Two bipolar electrodes were implanted in the pre- and postanastomosis stomach. Electromyographic recordings were performed intermittently for 8 to 13 weeks in fasting and after feeding. In one of the 6 dogs, 11 weeks after the initial surgery, one half of the anterior muscle wall of the greater curvature side was reapproximated.
In fasting, the BER interval in the preanastomosis remained unchanged, but that in the postanastomosis became prolonged. After feeding, the BER interval in the postanastomosis was shortened and showed an advancement to close to that in the preanastomosis. 3 weeks after reapproximation of partial muscle wall, the BER interval in the postanastomosis recovered to the same BER interval as in the preanastomosis in fasting and after feeding stages. Dysrhythmia in the postanastomosis was of temporal occurrance.
These results suggest that an inherent automatism in the gastric wall plays a role in the recovery of the BER interval and close muscle approximation is essential for propagation of gastric electrical activities.

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In order to clarify the propagation mechanism of the canine gastric basic electrical rhythm (BER), a complete transection-reanastomosis was done in the lower corpus, corpus-antrum juncticn or middle pyloric antrum in each group of 3 dogs which had been equipped with 4 bipolar electrodes.
At the time of the transection-reanastomosis, 4 pacing electrodes were also implanted. The BER frequency in the preanastomosis remained unchanged regardless of the site of transection-reanastomosis, while that in the postanastomosis was markedly reduced, but gradually recovered to show the synchronization with the BER in the preanastomosis.
Pacing of the gastric BER in the early stage (about 10 days post op.) when the synchronization was noted, was not established through anastomosis. However, pacing in the late stage (about 30 days post op.) was established through an astomosis.
Dysrhythmia in the postanastomosis were observed to occur in high incidence in the early postoperative period, but subsequently declined to the same incidence as in the controls.
Therefore, the synchronized phenomenon is due partly to the recovery of the inherent automatism of the gastric wall and due to subsequent propagation of the BER through anastomosis.
Dysrhythmia in the postanastomosis were of temporal occurrence.

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The motility of the bile ducts of the pigeon and the effects of autonomic drugs on it were studied in vivo and in vitro.
Peristalses which originated rhythmically at the hepatic end of the duct propagated to the duodenal end and excreated the bile into it. Antiperistalses did not occur in vivo. The intervals of peristalses of the duct in vivo changed variably while those of the spontaneous contractions in the isolated duct were fairly constant. No synchronization between the electrical activities recorded at the duodenal end of the duct and the duodenum close to the duct was observed.
Cholinergic drugs increased motilities of the duct and duodenum. Adrenaline, noradrenaline and phenylephrine induced the excitation of the duct and isoprenaline slight inhibition. All of these sympathomimetic drugs inhibited duodenal motility. The excitatory effect was abolished by α-adrenergic blocking agent, and the inhibitory one was abolished by α-and/or β-adrenergic blocking agents.
These results suggest that the bile duct is functionally independent of the duodenum and responsibility of the adrenergic drugs are different between two organs.

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