抗菌肽对肉牛生长性能及经济效益的影响OA北大核心CSTPCD

The aim of the experiment was to study the effects of different levels of antimicrobial peptides on the growth performance,rumen fermentation parameters,serum immunity,and breeding economic benefits of Simmental hybrid beef cattle.A total of 32 healthy Simmental crossbred beef cattle with similar body weight were randomly divided into four groups,with eight replicates per group and one beef cattle per replicate.Beef cattle in the control group were fed a basal diet,and those in the test group A,group B,and group C were fed diets containing 2,4,8 g/(head·d)antimicrobial peptides,respectively.The pre-test lasted for seven days and the formal test lasted for 150 days.The results showed that compared with the control group,the final weight and average daily gain in the test group B and group C were significantly increased(P＜0.05),while the ratio of feed to gain was significantly decreased(P＜0.05).The pH value and bacterial protein concentration of rumen fluid in test group B and group C were significantly increased(P＜0.05),and the ratio of ethylene to propylene was significantly decreased(P＜0.05).The rumen acetic acid concentration in all the test groups was significantly decreased(P＜0.05).The serum level of interleukin-4 was significantly increased(P＜0.05),and the serum level of interleukin-6 was significantly decreased in all the test groups(P＜0.05).The levels of interleukin-10,immunoglobulin M and immunoglobulin G in test group B and group C were significantly increased(P＜0.05).Compared with the control group,the weight gain income in the test group A,group B,and group C was increased by 10.40％,22.34％,and 23.55％,and the profit was increased by 19.31％,46.54％,and 48.45％,respectively.The study indicates that adding appropriate amount of antimicrobial peptides in beef cattle breeding can improve growth performance,promote rumen fermentation function,enhance immune function and increase breeding profits,and adding 4 g/(head d)antimicrobial peptides is more appropriate.