Digestibility of Edible Domestic Waste by Sheep

Seven young rams, equipped with simple cannulae in rumen, duodenum, and terminal ileum, were fed diets that contained 90% edible domestic waste (experimental group) or concentrate of grains and soybean meal (control group) and 10% pelleted wheat straw in a crossover-design metabolism trial. Mean apparent digestibility of organic matter, nitrogen, fat, and gross energy for experimental and control treatments, respectively, were: 73.4, 82.9; 65.8, 73.8; 66.6, 70.8; and 74.4, 81.8%. Percents of digested nitrogen retained in the body were 33.0 for the experimental group and 37.2 for the control. The edible domestic waste contributed less available carbohydrates and s-glucose polymers to the diet, and 92.4% of the latter "disappeared" in the reticulo-rumen. Total nitrogen flow to the small intestine was 15% greater than the amount consumed daily in either of the diets. A net increase of 44% in the flow of fat to the small intestine was observed with the control diet whereas with the edible domestic waste diet there was a net loss of 20% between mouth and duodenum. There were no differences between diets in pH, total and major three volatile fatty acids in the rumen fluid. Ammonia-nitrogen concentration was lower in the domestic waste diets. Results are discussed in relation to the nutritive value of edible domestic waste as a supplier of protein and energy for ruminants.