A radiological study of gastric (abomasal) emptying in calves before and after vagotomy.

Abstract

SUMMARY1. Gastric emptying has been studied in the conscious, standing calf by lateral radiography and fluoroscopy of radiopaque meals instilled into the abomasum before and after vagotomy.2. Bilateral cervical vagotomy proved to be the only certain way of achieving total vagal transaction. By instillation of milk into the abomasum through a cannula calves were maintained in normal, healthy condition for up to 36 days after vagotomy.3. Motility of the antrum was not impaired by vagotomy so that some movement of gastric chyme to the duodenum occurred within minutes of instillation into the abomasum. Complete transference of the test meal was, however, delayed after vagotomy.4. The greatest effect of vagotomy appeared to be on the abomasal body so that inadequate amounts of chyme were transferred to the antrum for pumping to the duodenum.5. Delay in passage of contrast material through the intestine was related to delay in gastric emptying although vagotomy may have affected the intestine directly.6. Following vagotomy the abomasum showed a resumption of normal motility and emptying after 7-29 days. This effect of vagotomy is similar to that seen in the simple stomach and is probably due to the establishment of intrinsic gastric control.

The Effects of Vagotomy on the Abomasum in Calves: Radiography and Protein Gene Product 9.5 Immunohistochemistry.

“…The corpus region was influenced earlier and more severely than other regions. This finding may be related to the fact that vagotomy had a greater effect on the motor activity of the corpus than on that of the pyloric region of the abomasum [1,21]. Furthermore, it may also be associated with the more numerous vagal nerve endings in the lesser curvature than in the greater curvature [15].…”

“…Although a vagal nervous dysfunction has been suggested as a possible cause of abomasal disorders [16], vagal nerve injury in the abomasal wall is still uncertain. The distribution of vagal nerve endings in the sheep stomach has been reported after short-term vagotomy [15], however, the long-term effects of vagotomy on the mural innervation of the ruminant stomach have not been described.Radiographic studies of the abomasum of lambs and calves before and after vagotomy were mostly undertaken during motility [17] and abomasal emptying [1]. The former was a short-term investigation while the latter maintained the calf after vagotomy by cannulation feeding into the abomasum.…”

“…Radiographic studies of the abomasum of lambs and calves before and after vagotomy were mostly undertaken during motility [17] and abomasal emptying [1]. The former was a short-term investigation while the latter maintained the calf after vagotomy by cannulation feeding into the abomasum.…”

Oesophageal and diaphragmatic activity during sucking in lambs

“…Newhook & Titchen (1974) showed in lambs, and Bell, Holbrooke & Titchen (1977) in calves, that although sucked material accumulated in the oesophagus after bilateral cervical vagotomy, it still passed caudally along it. Factors which contribute to such passage are the vis a tergo derived from the buccopharyngeal movements of swallowing, the influence of gravity and the opportunity for material to pass from the paretic oesophagus of vagotomized animals when the vertebral fibres forming the hiatus oesophageus are relaxed during expiration.…”

A Mechanism of Excessive Accumulation of Abomasal Gas in Vagotomized Cattle Determined using Fluoroscopy

“…The balance between the activity of these vagal branches and that of the intrinsic submucosal plexus determines the motility of each gastric chamber [11]. In one study [2], thoracic dorsal and ventral vagotomy was performed in 2-week-old calves. This inhibited contractions in the pyloric part and body of the abomasum; leading to reduced abomasal motility; hence, the movement of ingesta from the abomasum to the duodenum was greatly retarded.…”