Effect of dietary N-carbamoylglutamate on blood metabolite and lactation performance of high yielding dairy cows

摘要

IntroductionHigh yielding dairy cows fed diet rich in protein impaired the ureagenesis.While disturbancein urea cycle may interfere with process that improves the AA,limitationfor milk protein synthesis(Lobley et al.,1995),and decreased feed intake and milk production (Purdie et al.,2009).Arginine (Arg) plays a key role in ureagenesis and could enhance the angiogenesis and lactogenesis (Morris,2009).Supplementation of Arg increased milk production in cows (Chew et al.,1984).Due to the high rurnen degradation,feeding rumen-protected Argseemed to be uneconomical.Altematively,N-carbamoylglutamate (NCG),a stable structural analogue of N-acetylglutamate which activated Arg synthetic pathway (Wu et al.,2004),was of relatively lower rumen degradation rote and known as a potential Argraiser (Chacher et al.,2012).However,the effect of NCG in dairy cows has not been determined.Thus,the objective of the current study was to determine the effect of NCG onblood metabolite and milk production in high yielding dairy cows.