饲粮中添加包被叶酸对奶牛产奶及繁殖性能的影响OA北大核心CSTPCD

The experiment aimed to investigate the effects of coated folic acid supplementation in feed on the milk production performance,reproductive performance,and reproductive hormone levels in early lactation dairy cows.A total of 80 Holstein cows were selected five weeks postpartum and randomly divided into four groups with 20 replicates in each group and one cows per replicate.Group A(control group)was fed a basal diet,while Groups B,C,and D were supplemented with 35,70,105 mg/(cow·day)of encapsulated folic acid in their basal diet,respectively.The preliminary period lasted for seven days,and the formal experimental period was 82 days.The results showed that Groups C and D had significantly higher milk production in August compared to Group A(P＜0.05).In September,Group C had a significantly higher milk protein percentage than Groups A,B,and D(P＜0.05).The first service conception rate for Groups C and D increased by 2.95％and 5.25％,respectively,compared to Group A,and the pregnancy rate at 150 days increased by 5.88％and 2.02％,respectively.At day 21,the estradiol(E2)content in Group A was significantly higher than in Groups C and D(P＜0.05),while the progesterone(P4)content in Groups C and D was significantly higher than in Group A(P＜0.05).The study indicates that the supplementation of 70 mg/(cow·day)of encapsulated folic acid in the diet can help improve the milk production and reproductive performance of high-yielding dairy cows in large-scale dairy farms.