酵母发酵饲料对奶牛生产性能、血浆生化、免疫性能及抗氧化指标的影响OA

This experiment was conducted to investigate the effects of yeast fermented feed on production performance,plasma biochemical parameters,immune function and antioxidant capacity of mid-lactating dairy cows.A total of 48 healthy second-parity Holstein dairy cows with the same days in milk[(143±6)d]and milk yield[(35.13±0.61)kg/d]were randomly divided into control group and experimental group with equal number of individuals.Cows in the control group were fed a basal diet,while those in the experimental group were supplemented with 1.5 kg/(head·d)of yeast fermented feed on the basis of the basal diet.The pre-test period lasted for 7 days,and the formal test period was 45 days.The results showed that compared with the control group:① there was no significant difference in feed intake of the experi-mental group(P>0.05);the apparent digestibility of neutral detergent fiber(NDF)and acid detergent fiber(ADF)was extremely significantly increased(P<0.01);while the apparent digestibility of dry matter,crude protein and crude fat showed no significant differences(P>0.05).② The milk yield of the experimental group was significantly increased(P<0.05),the milk somatic cell count was significantly decreased(P<0.05),and the yields of lactose,milk fat and milk protein were extremely significantly increased(P<0.01).③ No significant differences were observed in the contents of plasma glucose,total pro-tein,albumin,alanine aminotransferase,aspartate aminotransferase and urea nitrogen in the experimental group(P>0.05),whereas the contents of plasma total cholesterol and triglycerides were extremely signifi-cantly decreased(P<0.01).④ The contents of plasma immunoglobulin G,immunoglobulin M,total antioxi-dant capacity and superoxide dismutase in the experimental group were significantly increased(P<0.05),the content of plasma malondialdehyde was significantly decreased(P<0.05),while the contents of immunoglobu-lin A and glutathione peroxidase showed no significant differences(P>0.05).In conclusion,supplementation of 1.5 kg/(head·d)yeast fermented feed in the diet of mid-lactating dairy cows can improve their production performance,reduce plasma lipid levels,and enhance the immune and antioxidant capacity of the body.