Biuret—A Source of NPN for Ruminants

Abstract

A series of studies on the toxicity and nitrogen utilization of biuret as a source of NPN for sheep and cattle is reported. Critical toxicity tests were conducted with sheep. Metabolism studies were conducted with sheep and cattle. A growth and reproduction study with sheep was conducted over a period of 593 days. The following general conclusions are drawn: Biuret fed at levels to supply a significant part of the nitrogen requirements was neither acutely nor cumulatively toxic to sheep. Growth, reproduction, and wool production did not seem to be adversely affected when sheep were fed biuret-containing rations. Positive nitrogen balances were obtained with sheep and steers fed rations in which biuret nitrogen furnished a major part of the total nitrogen intake. Satisfactory growth and reproduction were obtained in sheep fed low nitrogen rations supplemented with biuret. The utilization of biuret nitrogen in comparison with urea nitrogen appeared to be influenced by level of feed intake. These results indicate that biuret can be used to increase the flexibility of NPN use in ruminant rations.