Study On The Toxicity Of Curcumin And Bacillus Subtilis Mixed Feed Additives And Its Effect On Blood Biochemical Indexes And Milk Performance Of Dairy Cows

In order to explore the safety of curcumin and Bacillus subtilis mixed feed additives,and to further study its effect on the blood biochemical indicators and milk production performance of dairy cows,the following studies were made.The first part is to carry out toxicity research on mixed feed additives.(1)Acute toxicity test in mice:The test adopts the maximum tolerance method,20 Kunming mice are selected into male and female groups.Oral gavage was observed continuously for 14 days to record the poisoning and death of mice.(2)Mouse sperm deformity test:25 male Kunming mice were randomly divided into 5 groups,namely blank control group,positive control group,high,medium and low dose group,which were gavage once a day for 5 days.35 days after the first gavage,the mice were sacrificed,epididymal slices were taken,fixed with methanol,and stained with eosin.Calculate the sperm deformity rate.(3)Micronucleus test of mouse bone marrow cells:50 Kunming mice,were randomly divided into 5 groups,half male and one female,.The group was designed with the same mouse sperm deformity test.Oral gavage was given by gavage 2 times at 24h intervals Test substance.Six hours after the last administration of the sample,the mice were sacrificed,their femurs were cut,bone marrow fluid smears were taken,fixed with methanol,and Giemsa staining.Calculate the micronucleus rate and the ratio of polychromatic red blood cells to positively stained red blood cells.(4)30-day feeding test in rats:80 SD rats,male and female,were randomly divided into 4 groups,namely blank control group,high,medium and low dose group,which were gavaged once a day for 30 consecutive days.Observe the general behavior status,poisoning symptoms and death of rats every day,and analyze the effects of the test substance on the body weight,food intake,food utilization,blood biochemical indicators,blood routine indicators,organ index and main tissues and organs.The result shows:(1)Acute toxicity test:During the test period,the mice in each group were in good spirits,with normal body hair,normal activities,no symptoms of poisoning,and no death.(2)Mouse sperm deformity test:the sperm deformity rate of the high,medium and low dose groups was not significantly different from that of the control group(P>0.05).The positive control cyclophosphamide group had a significantly higher sperm deformity rate than the control group(P<0.01).(3)Micronucleus test of mouse bone marrow cells:There was no significant difference in the micronucleus rate of bone marrow cells of mice in the high,medium and low dose groups compared with the control group(P>0.05).The mice in the positive control cyclophosphamide group The micronucleus rate of bone marrow cells was significantly higher than that of the control group(P<0.01).(4)30-day feeding test in rats:body weight,weight gain,food intake,food utilization,blood biochemical indicators,organ weight and organ index of female and male rats in different dose groups at different periods compared with the control group Not significant(P>0.05),no pathological damage to important organs of rats.The second part is to study the effect of mixed feed additives on milk cow's blood biochemical indicators.A single factor test design was used to randomly divide 90 cows into 9 groups according to the amount of additives,10 replicates in each group.A blank control group;a positive control group;a mixed feed additive high,medium and low dose group;a curcumin high,medium and low dose group,Bacillus subtilis middle-dose group.Collect blood regularly to measure blood biochemical indicators,regularly record milk production,and determine milk composition at 7th and 28th days.The results showed that:at 7 d,the total protein content in the serum of cows in the high-dose,medium-dose mixed feed additive groups was significantly higher than that in the blank control group(P<0.05);at 28d,the high-dose and medium-dose mixed feed additive groups The total protein content in the serum of cows in the group and low-dose group was significantly higher than that in the control group(P<0.05).In terms of milk production,cows in the positive control group,the medium-dose group with mixed feed additives,and the high-dose curcumin group had significantly higher than the blank control group(P<0.05).The milk protein percentage and non-fat solids in the milk in the mixed feed additive medium-dose group and curcumin high-dose group were significantly higher than that in the blank control group(P<0.05);the positive control group,mixed feed additive medium-dose group,turmeric The number of somatic cells in milk in the positive control group,medium-dose group with mixed feed additives,curcumin medium and high-dose group was significantly lower than that in the blank control group(P<0.05).Conclusions:The mixed feed additive has no acute toxicity,genotoxicity and subchronic toxicity,and can be safely consumed as a new type of feed additive.It can increase the total protein content,increase milk production,increase milk protein rate,non-fat fat solids,reduce the number of somatic cells,and improve milk quality in the serum of lactating cows.