Study On The Effects Of Bile Salt In Dairy Cows Diet

Objective: To investigated the feeding effect of bile salts on cows.This experiment determined the milk yield,milk composition,nutrient digestibility and serum biochemical indexes of cows to judged the feeding effect of bile salts on cows.It provides basic theoretical guidance and data support for scientific and rational addition of bile salts in dairy cow diets.Methods: Experiment 1: Effect of feeding bile salts on milk yield and milk composition of cows.Forty mid-lactation cows were selected according to the principle of similar lactation volume,parity,weight and body condition.The experiments were divided into control group and experimental group with 20 cows in each group.The control group was fed with basic diet,when the experimental group was fed with basic diet which added 0.2% bile salts.The cows of the two groups were fed in different fences and fed and drank freely during the experimental period.The preliminary period is 15 days and the ongoing period is 30 days.Measuring the lactation volume every 2 days and the milk composition every 3 days during the trial period.Experiment 2: Effect of feeding bile salts on nutrient digestibility of cows.Determining the apparent digestibility of dry matter,crude protein,crude fat,neutral detergent fibers and acid detergent fibers by endogenous indicator method at the end of the trial period.Experiment 3: Effect of feeding bile salts on serum biochemical indexes of cows.Collecting blood from the tail vein of cows and prepared serum by separating at the end of the trial period.Then The determining the contents of urea,glucose,triglyceride,total cholesterol,low density fat eggs and high density fat eggs in serum of cows.Results:(1)There was no significant difference in average daily lactation between the experimental group and the control group(P>0.05).The milk fat content of the experimental group was significantly higher than control group(P<0.05),and there was no significant difference in milk protein,milk solids,non-protein nitrogen content and somatic cell number(P>0.05).(2)The crude fat digestibility of the experimental group was significantly increased by 4.11%(P<0.05)compared with the control group,and the apparent digestibility of acid detergent fiber of the experimental group was significantly increased compared with the control group(P<0.05),while the apparent digestibility of dry matter,crude protein and neutral detergent fiber of the experimental group was not significantly different from the control group(P>0.05).(3)The contents of blood glucose,blood urea nitrogen,total cholesterol and triglyceride in the experimental group were significantly lower than those in the control group(P < 0.05),but the contents of high density lipoprotein and low density lipoprotein were not significantly different between the two groups(P>0.05).Conclusion:The results showed that feeding bile salts could increase the milk fat content,apparent digestibility of crude fat and acid detergent fibers,meanwhile it could decrease the contents of blood glucose,blood urea nitrogen,triglyceride and cholesterol.There were no significant effects on the average daily milk yield,milk protein,milk solids,non-protein nitrogen,somatic cells,high density lipoprotein and low density lipoprotein.