Effect of Amino Acid Balance Diet on Production Performance,Serum Biochemical Indexes and Economic Benefits in Dairy Cows

This experiment was conducted to study the effect of amino acid balance diet on production performance,serum biochemical indexes and economic benefits in dariy cows.36 healthy Holstein cows in the early lactation period were selected,the average number of lactation (DIM) was (39.69±12.48) d,the average parity was 3.02±0.64.Principle of experiments using single factor randomized experimental design accroding to age,milk yield,parity identical same or similar,the 36 Holstein cows were assigned by random block design to 3 groups,and each group were 12 cows.The control group cows were fed with TMR diets only adding rumen-protected methionine (HMBi);Diets of group 1 and 2 were on the basis of control group,respectively adding two kinds of rumen-protected lysine levels in order to balance the amino acid in diet.The results showed as follows:① Compared with control group,the feeding conversion ratio in groups 1 and 2 were increased by 10.60% and 11.26% (P>0.05),respectively,while the dry matter intake had no significantly changed (P>0.05),the 4% average daily milk yield in groups 1 and 2 were significantly increased by 8.65% and 10.58% (P<0.05),respectively,and the milk fat and milk protein yield in groups 1 and 2 were significantly or extremely significantly increased (P<0.05;P<0.01),respectively.Adding amino acid balance diet had no significantly effects on reproductive performance and health conditions in dariy cows (P>0.05).② When feeding the amino acid balance diets for 60 days,the contents of GLU and TAA in serum of dairy cows were significantly increased (P<0.05),while the BUN content was significantly decreased (P<0.05).③ Compared with control group,the economic benefits of groups 1 and 2 were increased by 15.09 and 16.36 yuan/(head·d).The results indicated that feeding the amino acid balance diets could significantly improve production performance of dairy cows,and there was a tendency to improve metabolic conditions.