Biuret and urea in maintenance and production diets of cattle

Abstract

SUMMARYA series of five field trials with cattle was carried out to study the comparative efficiency of utilization of urea and biuret in various maintenance and production nutritional situations. It was shown that in maintenance diets with energy intake above 8 Meal/head/day and where half of the nitrogen requirements of the animals was contributed by one of the two non-protein nitrogen (NPN) sources, biuret was utilized 30% more efficiently than urea. No difference in the degree of utilization of urea or biuret was apparent when the energy was reduced to 6·7 Meal/head/day. On the other hand, a high intake of nitrogen in production rations had a masking effect on the nitrogen contribution of the NPN sources and no significant differences in bodyweight gain were recorded.

Studies on the adaptation of the rumen to the hydrolysis of biuret in cattle

“…This draws attention to the importance of the degree of adaptation of the rumen to the hydrolysis of biuret and its association to effective changes in rumen ammonia concentration. In this context, the slow release of ammonia from biuret in relation to the overall N metabolism of ruminants in contrast to the effect of urea, should be considered as a phenomenon of high importance to the nitrogen economy of ruminants, in general, and especially during periods when low protein diets are fed (Kondos & Mutch, 1975).…”

“…Once adaptation is complete, reports indicate that biuret becomes a nitrogen source as useful as urea (Meiske et al 1955;Gaither et al 1955;McKenzie & Altona, 1964;Clark, Barratt & Kellerman, 1965;Turner & Raleigh, 1969) or even superior to it (Berry et al 1956;Hatfield et al 1959;Karr et al 1965;Kondos & Mutch, 1975).…”