Effect of duodenal cannulation on abomasal emptying and secretion in the preruminant calf.

Abstract

SUMMARY1. The effect of re-entrant cannulation of the duodenum on digesta flow from, and secretion into, the abomasum of the preruminant calf was studied.2. Calves fitted with abomasal cannulas and, at the same time or later, with re-entrant duodenal cannulas were given, by abomasal infusion, test feeds containing glucose and minerals. Net volumes of secretary fluids entering the abomasum and amounts of digesta flowing to the duodenum were estimated from changes in concentrations of water soluble markers (phenol red and polyethylene glycol) in digesta samples collected from an abomasal cannula.3. Amounts of abomasal contents, net volumes of secretary fluids and digesta flow to the duodenum for calves fitted with only an abomasal cannula did not differ significantly from those obtained for animals with abomasal and re-entrant duodenal cannulas.4. Collecting digesta from a re-entrant cannula and returning it promptly to the animal did not affect net volumes of secretary fluids. Under these conditions with cannulas open to the atmosphere, rather than being connected together, the amounts of digesta entering the duodenum increased slightly but differences were not significant.5. Weight gains of calves fitted with abomasal and duodenal cannulas were similar to those of intact animals.6. It is concluded that in calves receiving liquid feeds duodenal re-entrant cannulation is a suitable preparation for investigating digestive processes of the abomasum.

Effect of suckling isotonic or hypertonic solutions of sodium bicarbonate or glucose on abomasal emptying rate in calves

“…We do not believe that the presence of an abomasal cannula altered the emptying rate in the calves in our study because placement of a percutaneous endoscopic gastrostomy tube did not slow gastric emptying in cats, 66 and the presence of the much more invasive duodenal reentrant cannula did not alter abomasal emptying rate in milk-fed calves. 67 In conclusion, in contrast to the conclusion of previous studies 25,26 in calves, our results indicate that the effects of osmolarity and glucose concentration on abomasal emptying rate in euhydrated calves are similar to those in euhydrated monogastric animals. Whether slowing of the abomasal emptying rate in dehydrated diarrheic calves suckling an electrolyte solution is clinically important remains to be determined.…”

Ultrasonographic measurement of abomasal volume, location, and emptying rate in calves

“…36 We do not believe that the presence of an abomasal cannula altered emptying rate in the study calves because the placement of a percutaneous endoscopic gastrostomy tube does not slow gastric emptying in cats 37 ; furthermore, compared with an abomasal cannula, the presence of a much more invasive duodenal reentrant cannula does not alter emptying rate in milk-fed calves. 38 Ultrasonographic measurements indicate the change in stomach volume with time, whereas scintigraphic measurements indicate the rate of disappearance of a radioactive agent from the stomach. 11 At any time, the abomasal volume in calves is the sum of the preprandial volume, suckled volume, and volume of fluids secreted by the salivary glands and abomasum, minus the volume emptied from the abomasum.…”

Characterization of products from in vivo and in vitro gastric digestion of milk replacers containing whey proteins

“…Also, the cannula may physically restrict or change the course of digesta flow, because peristaltic contractions failed to propagate beyond the reentrant cannula (Wenham and Wyburn, 1980). Nevertheless, Sissons and Smith (1982) observed that inserting a reentrant cannula in the proximal duodenum of the preruminant calf did not lead to major disturbances in net abomasal secretion and digesta flow to the duodenum. CONCLUSION When preruminant calves were fed a milk diet, ingested caseins were mainly (92-94%) retained in a clot and released progressively from the stomach as peptides.…”