Effects Of Compound Astragalus Feed Additive On Performance,Serum Biochemistry And Uterine Recovery Of Dairy Cows In Late Perinatal Period

This experiment was conducted to investigate the effects of different dosages of compound Astragalus herb additive(CCM)on performance,serum biochemistry and reproductive performance of dairy cows in late perinatal period.Sixty healthy Holstein perinatal cows with the same parity and similar body weight were randomly divided into 4 groups with 15 cows per group.Compound Astragalus herb feed additive 0,675,1350 and 2700 g/d was added into the basic diet.The experiment began on the day of cow delivery and lasted for 21 days.The results were as follows:In experiment 1,the effects of different dosages of compound Astragalus herb feed additives on performance and body condition of dairy cows in the late perinstrine period were investigated.The results were as follows:(1)Compared with 0 g/d group,dietary supplementation of 1350 g/d CCM additive significantly increased milk yield(P<0.05)and significantly increased feed intake in late perinatal period(P<0.05).(2)Compared with 0 g/d group,dietary 675 g/d CCM additive increased milk protein percentage and decreased milk fat percentage;CCM additive can significantly reduce SCC and MUN in milk(P<0.05).(3)Compared with 0 g/d group,CCM additive can alleviate the body condition decline of cows in the late perinatal period,and 2700 g/d has the most obvious effect.Experiment 2 explored the effects of different dosages of compound Astragalus herb feed additives on serum biochemistry of dairy cows in the late perinatal period.The results were as follows:(1)Compared with the 0 g/d group,the HCT,PLT and MPV of the 675 g/d group showed a higher trend than that of the other experimental groups.The 10d blood samples showed that the MVC of the 675d/g group showed a higher trend than that of the other experimental groups(0.05<P<0.1).The 1350 g/d group was significantly higher at 21dPLT than other dose groups and control groups(P<0.05).Dietary CCM additive can promote the blood circulation of animals,reduce the risk of postpartum hypertension,increase the PLT of cows in the late perinatal period,promote postpartum wound recovery and improve the immune function of animals.(2)Compared with 0 g/d group,there was no significant difference in humoral immune cell level among all groups after dietary CCM additive.(3)Compared with 0 g/d group,675 g/d group had a higher trend than control group(0.05<P<0.1).The results of PV on the 15th day showed that there was a tendency of higher than 0 g/d in all dose groups(0.05<P<0.1);The results of FIB at 10d showed that the 675 g/d group had a higher tendency than the other control groups(0.05<P<0.1);meanwhile,the results of FIB at 15d and 21 d showed that all dose groups were significantly higher than the 0 g/d group(P<0.05).CCM additive can promote blood coagulation,accelerate uterine relapse and reduce the risk of thrombosis of dairy cows.Among them,each dose group has obvious effect.(4)Compared with 0 g/d group,serum IgG in 2700 g/d group was higher than that in other dose groups and control group at 21 days(0.05<P<0.1);At 21 days,serum IgM in 675 g/d and 2700 g/d groups was significantly higher than that in control group(P<0.05);At 21 days,serum IgA 1350 g/d and 2700 g/d groups were significantly higher than other dosage groups and control group(P<0.05).The CCM additive in feed had a significant effect on improving the immune ability of animals,and feeding 1350 g and 2700 g CCM additive every day had a significant effect.(5)At 0d,IL-2 level in 675 g/d group was significantly different from that in other dose groups and control group(P<0.05),and at 5d,IL-2 level in 2700 g/d group was significantly higher than that in other dose groups and control group(P<0.05).At 1d,IL-6 in 0 g/d group was significantly higher than that in other dose groups(P<0.05);at 21d,IL-6 in 2700 g/d group was significantly higher than that in 675 g/d group,and there was a tendency to be higher than that in other dose groups(P<0.05);At 21 days,CRP level in 0 g/d group was significantly different from that in dose group(P<0.05).The CT level of the 675 g/d group was significantly different at 1d(P<0.05),and the CT level of the 0 g/d group at 10d and 15d was significantly lower than that of the other dose groups(P<0.05).CCM additive can improve the immune function and anti-inflammatory level of dairy cows in the late perinatal period,promote postpartum wound recovery and reduce the risk of postpartum bone disease to a certain extent,and the effect of 1350 g/d is better in the overall dose group.Experiment 3 explored the effects of compound Astragalus herb feed additive in different dosage groups on reproductive hormones and reproductive performance of dairy cows in the late perinatal period.The results were as follows:(1)The results at 10 days showed that E2 in 1350 g/d and 2700 g/d groups was significantly lower than that in control group and other dose groups(P<0.05),and P level in 2700 g/d group was significantly lower than that in control group and other dose groups(P<0.05);The results at 15 days showed that FSH in 2700 g/d group was higher than that in control group(0.05<P<0.1).The results showed that PGF2α level in control group was significantly higher than that in all dose groups(P<0.05),PRL level in 2700 g/d group was significantly higher than that in control group(P<0.05),LH level in control group was significantly lower than that in all dose groups(P<0.05).(2)The mating times and empty days of 675 g/d and 1350 g/d groups were lower than those of control group(0.05<P<0.1);The highest mating rate was found at 675 g/d after the first centralized mating of cows.The highest mating rate was found at 1350 g/d 100 days after delivery.