Work

Effect of defaunation on protein and fibre digestion in sheep fed on ammonia-treated straw-based diets with or without maize

Year: 1990

Type: article

Abstract: Using a defaunating method which preserved bacteria and fungi in the rumen, the effect of protozoa on protein and fibre digestion was studied in six adult wethers in relation to the nature of the diet. Sheep were given daily, 42 g dry matter (DM)/kg metabolic body-weight (W0.75), one of two isonitrogenous diets: one contained ammonia-treated wheat straw as the only energy source (diet S) and the other was supplemented with maize grain pellets (diet SM). Mean daily intakes (g/d) of nitrogen, neutral-detergent fibre and acid-detergent fibre were respectively 22, 573 and 373 for diet S and 23, 450 and 334 for diet SM. Elimination of protozoa increased duodenal non-ammonia-nitrogen flow. This result was mainly due to an increase in microbial protein flow and, to a lesser extent, to a higher dietary protein flow. Defaunation markedly increased the efficiency of microbial protein synthesis. Maize-grain supplementation had a net positive effect on this variable in defaunated sheep, but not in faunated sheep. Cell-wall carbohydrates were less well digested in the defaunated rumen, and the negative effect of defaunation was greatest with the diet SM. Intestinal fibre digestion increased in the defaunated sheep especially in those fed on diet SM, but not enough to compensate for the decrease in rumen digestion.

Source: British Journal Of Nutrition

DOI: 10.1079/bjn19900078

Authors: K. Ushida, C. Kayouli, S. De Smet, J. P. Jouany

Institution: Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement

Language: English

Topic: Ruminant Nutrition and Digestive Physiology

Subfield: Animal Science and Zoology

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: bronze

Funder: Institut National de la Recherche Agronomique