酵母核苷酸对奶牛生产性能、乳品质、血清指标及经济效益的影响OA北大核心CSTPCD

The experiment aimed to investigate the effects of yeast nucleotides on the production performance,milk quality,serum indexes,and economic benefits of dairy cows.Forty healthy Holstein cows with similar body weight,parity,and milk yield were selected and randomly divided into four groups with ten replicates in each group and one cow in each replicate.The control group was fed a basal diet,while the experimental group 1,group 2,and group 3 were supplemented with 0.2％,0.4％,and 0.8％yeast nucleotides in the basal diet,respectively.The pretrial period was 10 days,and the formal experimental period was 60 days.The results showed that compared to the control group,the average daily feed intake of cows in experimental group 3 significantly increased(P＜0.05).The average daily milk yield of cows in experimental group 2 and group 3 significantly increased(P＜0.05),and the feed-to-milk ratio of cows in experimental group 2 significantly decreased(P＜0.05).Compared to the control group,the milk fat percentage of fresh milk from cows in experimental group 2 significantly increased(P＜0.05),the total somatic cell count in the milk of all experimental groups significantly decreased(P＜0.05).The incidence of mastitis in dairy cows in the experimental group was 0,which was significantly lower than that in the control group(P＜0.05).The serum immunoglobulin G(IgG)content of cows in experimental group 2 and group 3 was significantly higher than that of the control group(P＜0.05).The gross profit of experiment group 2 was 12.07％higher than that of control group,and the economic benefit was obviously improved.The study indicates that feeding yeast nucleotides can improve the production performance and milk quality of dairy cows,improve serum indexes,and enhance economic benefits,with a recommended addition of 0.4％of yeast nucleotides of feed.