Effects of graded removal of lysine from an intravenously infused amino acid mixture on lactation performance and mammary amino acid metabolism in lactating goats
Introduction Based on present knowledge of AA nutrition, post-absorptive efficiency of N use for milk or tissue proteins is determined by the amount of MP supplied relative to animal needs, the profile of absorbed EAA,and the rate of protein synthesis.Post-absorptive N efficiency would then be maximized if we could match an animals MP needs exactly with a diet well balanced in absorptive EAA profile.By maximal utilization of the strategy, Baker et al (1996) demonstrated that post absorptive N efficiency in pigs could be promoted to 85％, which is in agreement with the theoretical efficiency of the mammary gland to convert an ideal EAA profile into milk protein proposed by AFRC (1993).The ideal EAA profile and requirements for EAA are at present evaluated according to the theory of limiting AA, which predicates that protein synthesis is limited by the most deficient EAA relative to requirement (Mitchell and Block, 1946).The relative importance of individual mechanisms mediating the effects of EAA supply on milk protein synthesis has not been fully investigated.The aim of the present study was to observe the effects of a graded deficiency of Lys on milk production, mammary AA metabolism, circulating hormone levels, and phosphorylation status of selected agents in the mTORC1 pathway in lactating goats.
C.L.Guo Y.T.Li X.Y Lin M.D.Hanigan Z.G Yan Z.Y.Hu Q.L.Hou F.G.Jiang Z H.Wang
Ruminant Nutrition and Physiology Laboratory, College of Animal Science and Technology, Shandong Agricultural University, Taian 271018, P.R.China
国际会议
The 5h International Symposium on Dairy Cow Nutrition and Milk Quality(第五届“奶牛营养与牛奶质量国际研讨会)
北京
英文
187-188
2017-05-05（万方平台首次上网日期，不代表论文的发表时间）