饲用酵母对断奶前后犊牛生长性能、血清代谢物和瘤胃发酵性能的影响

Effects of feed yeast on growth performance,serum metabolites and rumen fermentation of calves before and after weaning

文章旨在研究饲用酵母对断奶前后犊牛生长性能、血清代谢物及瘤胃发酵性能的影响。试验将20头21 d、平均体重为(53.56±1.53)kg的犊牛随机分为2组,每组5个重复,每个重复2头。对照组犊牛在断奶前(21~48 d)和断奶后(49~70 d)饲喂基础日粮,酵母组犊牛在断奶前(21~48 d)和断奶后(49~70 d)饲喂基础日粮+2和4 g/d饲用酵母。试验结果:与对照组相比,酵母组70 d犊牛体重以及21~48 d、21~70 d平均日增重分别显著提高8.50%、16.90%和14.67%(P<0.05)。酵母组70 d犊牛血液胰高血糖素、49和70 d胰岛素样因子-1以及49 d干扰素-γ浓度较对照组分别显著提高16.35%、88.23%、76.02%和318.86%(P<0.05)。与对照组相比,酵母组犊牛瘤胃氨氮和丙酸浓度分别显著提高56.19%和24.04%(P<0.05),但乙酸与丙酸比值显著降低24.20%(P<0.05)。结论:在本试验条件下,断奶前后犊牛补充2和4 g/d饲用酵母可以提高血液胰岛素样因子-1和胰高血糖素浓度,进而提高犊牛体重和断奶后3周的平均日增重。

The experiment was conducted to investigate the effects of feeding yeast supplementation on growth performance,blood metabolites and rumen fermentation performance of calves before and after weaning.Twenty calves with an average body weight of(53.56±1.53)kg for 21 days were randomly divided into 2 groups with 5 replicates per group and 2 calves per replicate.Calves in the control group were fed the basal diet before weaning(21~48 d)and after weaning(49~70 d),while those in the yeast group were fed the basal diet+2 and 4 g/d of feeding yeast before and after weaning(49~70 d).RESULTS:Compared with the control group,the body weight of calves at 70 d and the average daily gain at 21~48 d and 21~70 d in yeast group were significantly increased by 8.50%,16.90%and 14.67%(P<0.05),respectively.Compared with the control group,plasma concentrations of glucagon,insulin~like factor~1 and interferon~γin yeast group at 70 d were significantly increased by 16.35%,88.23%,76.02%and 318.86%at 49 d,respectively(P<0.05).Compared with the control group,rumen ammonia nitrogen and propionic acid concentrations of calves in yeast group were significantly increased by 56.19%and 24.04%(P<0.05),respectively,but the ratio of acetic acid to propionic acid was significantly decreased by 24.20%(P<0.05).Conclusions:Feeding yeast supplementation of 2 and 4 g/d before and after weaning can increase blood insulin~like factor~1 and glucagon concentrations,thereby increasing body weight and average daily gain 3 weeks after weaning of calves under the present experimental conditions.