The crucial role of lysine in the hepatic metabolism of growing Holstein dairy heifers as revealed by LC-MS-based untargeted metabolomics  

作　　者：Fanlin Kong Yuan Li Qiyu Diao Yanliang Bi Yan Tu 

机构地区：[1]Beijing Key Laboratory for Dairy Cow Nutrition,Sino-US Joint Lab on Nutrition and Metabolism of Ruminants,Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural Affairs,Institute of Feed Research,Chinese Academy of Agricultural Sciences,Beijing 100081,China

出　　处：《Animal Nutrition》2021年第4期1152-1161,共10页动物营养（英文版）

基　　金：supported,in part,by the Key Research and Development Program of Hebei Province(19226621D);Earmarked Fund for Beijing Dairy Industry Innovation Consortium of Agriculture Research System,Chinese Academy of Agricultural Science and Technology Innovation Project(CAAS-XTCX-2016011-01);Fundamental Research Funds for Central Non-profit Scientific Institution(Y2019CG08);Agricultural Science and Technology Innovation Program(CAAS-ASTIP-2017-FRI-04);Science and Technology Open Cooperation Project of Henan Province(182106000035)Study on the Pattern of Diet Amino Acid for Different Physiological Stages of Heifers。

摘　　要：The objective of this experiment was to evaluate the effect of supplementing rumen-protected Lys based on a Lys-deficient diet on liver metabolism in growing Holstein heifers.The experiment was conducted for 3 months with 36 Holstein heifers(initial body weight:200±9.0 kg;7-month-old).Heifers were randomly assigned to 2 diets based on corn,soybean meal,alfalfa hay,and wheat bran:control,Lysdeficient diet(LD;0.66%Lys in diet),and Lys-adequate diet(LA;1.00%Lys in diet).The results showed no difference in growth performance between the 2 groups(P>0.05).However,there was a clear trend of increasing feed conversion rate with Lys supplementation(0.05<P<0.01).The serum urea nitrogen concentration was significantly decreased,and the aspartate aminotransferase-to-alanine aminotransferase ratio was significantly decreased by Lys supplementation(P<0.05).Moreover,growing heifers fed a Lys-adequate diet had lower levels of urine nitrogen excretion and higher levels of the biological value of nitrogen(P<0.05).Metabolomic analysis revealed that 5 types of phosphatidylcholine and 3 types of ceramide were significantly increased and enriched in sphingolipid metabolism and glycero phospholipid metabolism(P<0.05).His,Leu,and Asp levels were significantly decreased in the liver following Lys supplementation(P<0.05).In conclusion,Lys supplementation may promote the synthesis of body tissue proteins,as evidenced by significantly decreased amino acids in the liver and urine N excretion,it also improves hepatic lipid metabolism by providing lipoprotein precursors.

关 键 词：Growing Holstein heifer LYSINE Liver Untargeted metabolomics 

分 类 号：S823[农业科学—畜牧学]