Utilization of Urea by Sheep and Goats Fed High Roughage Diets

摘要

Two experiments were conducted to test the utilization of urea-containing high fiber diets by small ruminants. In Experiment I wheat straw/alfalfa hay diets were supplemented with 0, 1 or 2% urea to achieve 7, 10 or 13% crude protein equivalent. When fed to growing Toggenburg wether goats, voluntary intake was slightly lower (P.05) for the diet without urea. Digestibilities of dry matter and fiber (P .05) and crude protein (P .01) were lower for the diet without urea but not different for the diets with 1 or 2% urea. Less nitrogen was retained (P .01) on the zero-urea diet, with no difference between the 1 or 2% urea diets. In Experiment II urea was compared with soybean oil meal as a nitrogen source in low or medium fiber diets for growing, wethered Toggenburg goats or Suffolk sheep. All diets were adjusted to 11-12% crude protein equivalent.