首页|期刊导航|中国农业科学（英文版）|Effect of Different Protein Levels On Nutrient Digestion Metabolism and Serum Biochemical Parameters in Calves
中国农业科学（英文版）2008，Vol.7Issue(3)：375-380,6.
Effect of Different Protein Levels On Nutrient Digestion Metabolism and Serum Biochemical Parameters in Calves
Effect of Different Protein Levels On Nutrient Digestion Metabolism and Serum Biochemical Parameters in Calves
摘要
Abstract
The current study has been performed to examine the effects of different dietary protein levels on the growth,nutrient digestion and absorption,as well as biochemical parameters in calves.Nine healthy newborn calves were selected,randomly divided into 3 groups and fed 3 milk replacers with different protein levels(18,22,and 26%),respectively.Five period-digestion-metabolism trials were taken between 12-20,22-30,32-40,42-50,and 52-60 days after birth.All 3 groups showed a similar growth curve during 11 to 61 experimental days,however,the growth rate of the 22%crude protein(CP) group was 8.89%higher than that of the 18%CP group and 19.48%higher than that of the 26%CP group.respectively. The apparent digestibility of dry material(DM)declined gradually with age,whereas,the apparent digestibility of N,extract ether(EE)rose slightly.Compared to the 22%CP and 26%CP group,calves fed with 18%CP apparently had a lower digestibility than DM,EE,and nitrogen(N).The average apparent digestibilities of N were 69.39,75.36,and 74.55%, respectively.Both the apparent digestibility and retention of calcium(Ca)and phosphorus(P)were steady throughout the experiment,but the average apparent digestibility of P in the 26%CP group was only 63.83%,which was markedly lower than that of the 18%CP group(70.40%)and 22%CP group(69.73%).In addition,the sernm concentrations of total protein(TP),albumin(ALB),and globulin(GLOB)of the 22%CP group were higher than those in the 18%CP and 26%CP groups.The urea N(BUN)content in the 18%CP group,on the other hand,was significantly lower than that of the other two groups.The highest glucose(GLU)concentration was found in the 22%CP group(5.38 mmol L-1),at the end of the trials.The protein levels in the milk replacer affected the digestion metabolism of nutrition and the serum biochemical parameters of calves at different physiological phases.Calves fed with 22%CP milk replacer had a better growth performance than the other groups.关键词
calves,protein levels,milk replacer,apparent digestibility,biochemical parametersKey words
calves,protein levels,milk replacer,apparent digestibility,biochemical parameters分类
农业科技引用本文复制引用
LI Hui,DIAO Qi-yu,ZHANG Nai-feng,TU Yan ,WANG Ji-feng..Effect of Different Protein Levels On Nutrient Digestion Metabolism and Serum Biochemical Parameters in Calves[J].中国农业科学（英文版）,2008,7(3):375-380,6.基金项目
The financial support is from the National New Products Program of Ministry of Science and Technology of China (2005EC000007).The authors also thank all the crew at the Cangdafu Cattle Farm,Daxing District of Beijing,China,for their dedicated efforts. （2005EC000007）
