because these
compounds increase microbial protein synthesis potential in
the rumen (Grobner et al. 1982). However, the reduced energy
utilization efficiency observed for the F-TMR in the present
study could be due to excessive protein degradation and
increases in ruminal ammonia concentrations brought about
by feeding high levels (3% units more) of protein (Glimp and
Tillman 1965). The increased ammonia production in the
rumen can increase urea recycling, which is necessitated to
detoxify ammonia through formation of urea, (an energy
requiring process; Lobley 1992), thereby negatively affecting
energy utilization to a modest degree. It is expected that
decreasing the other protein components in the diet in future
studies can rectify the problem.