乳酸菌对苏尼特羊生长性能、肉品质及肠道微生物的影响.

【Objective】This experiment was conducted to investigate the effects of compound lactic acid bacteria on growth performance, slaughter performance, meat quality and intestinal microflora of Sunit sheep.【Method】Twelve 3-month-old Sunit sheep with similar body weight were randomly divided into control group（basal diet） and experimental group（basal diet supplemented with compound lactic acid bacteria）, with half male and half female, and slaughtered after feeding for 90 days. The growth performance, slaughter performance and longest back muscle quality of Sunit sheep at the 30th, 60th and 90th day were measured. Meanwhile, fresh feces were collected at the 0th, 30th, 60th and 90th day for high-throughput sequencing to analyze the effects of compound lactic acid bacteria on intestinal microbial diversity and composition of intestinal microflora of Sunit sheep.【Result】Compared with the control group, the total gain and average daily gain of experimental group at the 30th and 90th the day were significantly increased（P<0.05）, the ratio of bone to meat, loin eye area and pH24 after slaughter were significantly higher than those in the control group（P<0.05）, and the cooking loss was extremely significantly lower than that in the control group（P<0.01）. There were no significant differences in other performance and meat quality indexes between control group and experimental group（P>0.05）. The Chao1 and Ace in the experimental group was higher than in the control group（P<0.05）, which showed that feeding lactobacillus was beneficial for improving the diversity of gut microbiota. At the phylum level, gut microbiota of Sunit sheep mainly included Firmicutes and Bacteroidetes in two feeding methods. In the 30th and 90th day, the abundance of Firmicutes in the experimental group was higher than control group（P<0.05）, and the abundance of Proteobacteria was significantly lower than control group（P<0.05）. At the genus level, the abundance of Ruminococcaceae＿UCG＿010, unclassified＿f＿＿Lachnospiraceae, and Alistipes in the experimental group was higher than control group in the 30th day. However, the abundance of Succinivibrio in the experimental group was lower than in the control group（P<0.05）. Compared to control group, the abundance of Ruminococcaceae＿UCG＿010, unclassified＿f＿＿Lachnospiraceae, and Prevotella＿2 in the 60th day and the abundance of Alistipes, Prevotella＿1 and Treponema＿2 in the 90th day increased significantly in the experimental group（P<0.05）, while the abundance of Succinivibrio decreased（P<0.05）. 【Conclusion】In conclusion, lactic acid bacteria, as a natural and green substitute for antibiotics, has a positive impact on improving growth performance, slaughter performance, intestinal microbial composition and meat quality of Sunit sheep, providing theoretical reference for the development of lactic acid bacteria feed and improving the performance of house feeding sheep. [ABSTRACT FROM AUTHOR]