日粮添加不同种类和比例复合益生菌对湖羊瘤胃微生物群落的影响OA北大核心CSTPCD

High concentrate diet fattening can increase the daily weight gain of mutton sheep(Ovis aries),but also cause the rumen acid production and fermentation too fast,and the body metabolism imbalance.Complex probiotics can maintain the balance of gastrointestinal flora and promote the growth and development of ruminants through the synergistic action of various probiotics.To investigate the effects of different types and proportions of complex probiotics on rumen microbial community of Hu sheep,60 healthy male Hu sheep lambs with similar body weight and age were randomly divided into 4 treatment groups.The control group was fed basal diet,and experimental group1,2 and 3 were supplemented with 2%and 4%probiotic preparation FA1 and 2%probiotic preparation FA2 in the basal diet,respectively.After 60 d of feeding,the sheep were weighed,rumen fluid was collected to measure pH and detect rumen microbial composition through 16S rRNA sequencing of bacteria.The results showed as follows,compared with the control group,the average daily gain of experimental groups supplemented with probiotics showed an increasing trend,but no significant difference,and the average ratio of feed to gain was significantly decreased(P＜0.05).There were no significant differences in rumen microbial Alpha diversity and Beta diversity index among groups.The bacterial abundance of Clostridia UCG-014 significantly increased in experimental group 1.The bacterial abundance of Solobacterium significantly increased in experimental group 2.The bacterial abundance of Lachnospiraceae-NK3A20-group and Acidaminococcus significantly increased in experimental group 3.The functional pathway of cellulolysis in test group 2 was significantly reduced,and the content of crude fiber in feces was significantly increased(P＜0.05).The results showed that the addition of different types and proportions of complex probiotics in the diet could increase pH of rumen fluid and the abundance of anaerobic probiotics and improve the growth performance of Hu sheep.However,4%complex probiotics FA1 had a negative effect on the apparent digestibility of crude fiber.This study provides a reference for the theoretical research and production application of complex probiotics.