The Sites of Digestion of Fresh Pasture Species in the Gastro-Intestinal Tracts of Sheep

M.J. Ulyatt and J.C. MacRae

DSIR, Applied Biochemistry Division, Palmerston North

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Proceedings of the New Zealand Society of Animal Production. 1971, 31: 74-81

Sheep prepared with re-entrant cannulae in the proximal duodenum and terminal ileum were used to study the sites of digestion in the gastro-intestinal tract of 'Grasslands Ruanui' perennial ryegrass (R), 'Grasslands Manawa', short-rotation ryegrass (M) and 'Grasslands 4700' white clover (C).

The percentage of digestible energy that was digested, respectively, in the stomachs, small intestine, large intestine, was 61, 16, 23 for R, 48, 33, 19 for M, and 60, 35, 5 for C.

Similarly, the percentage of digestible nitrogen that was digested, respectively, in the stomachs, small intestine, large intestine, was 26, 63, 11 for R, 18, 71, 11 for M, and 32, 66, 2 for C.

It was considered that the higher liveweight gain obtained on M than R is due to the greater amount and quality of metabolites absorbed from the small intestine of M. The superiority of C ever the grasses was thought to be due to high small intestinal digestion coupled with a high volatile fatty acid production rate in the stomachs.

Keywords: NZSAPAB;

Last Updated 24-08-2000