Effect of dehydrated alfalfa products on the utilization of urea nitrogen in beef cattle.

Abstract

The addition of dehydrated alfalfa stem fraction meal (DAS) to a high-urea semipurified diet resulted in a nonsignificant effect on dietary nitrogen retention and on absorbed nitrogen retention. No differences in dry matter digestibility, digestible energy, rumen ammonia, blood urea and plasma free amino acids were observed. When the addition of dehydrated alfalfa meal (DEHY) was compared to the addition of DAS to a high-urea semipurified diet, no differences were noted in nitrogen retention or any of the other parameters. In a feeding trial steers fed a natural protein supplement gained significantly (P<.05) faster than those fed a Purdue 64 high-urea supplement containing DAS, distillers dried grains with solubles (DDGS) or one-half DEHY and one-half DDGS. Those fed supplements containing either DEHY or DAS gained at comparable rates (1.18 vs. 1.14 kg/day), but the difference in gain between those fed the natural supplement and those fed DEHY was nonsignificant, whereas that between the natural supplement and DAS was significant (P<.05).