An evaluation of the use of chromic oxide, polyethylene glycol and Cr-EDTA as markers for digestive studies along the small intestine of ruminants.

In cows, fitted with a T-shaped cannula in the duodenum and with a re-entrant cannula in the ileum, ileal recoveries were determined of Cr2O3, from impregnated paper and polyethylene glycol (PEG), introduced into the duodenum. The length of the collection periods of digesta was important. The mean transit time of both markers along the small intestine did not differ. In sheep, fitted with an infusion tube into the abomasum and with an ileal re-entrant cannula, PEG was recovered quantitatively over 10-h collection periods. In sheep, fitted with an infusion tube into the abomasum and with 4 T-shaped cannulae along the small intestine, flow rates of digesta in jejenum and ileum estimated with PEG and Cr-EDTA were similar. (Abstract retrieved from CAB Abstracts by CABI’s permission