酿酒酵母对湘中黑牛营养物质消化率、瘤胃发酵及血浆生化指标的影响

本试验旨在研究不同添加水平酿酒酵母对湘中黑牛生长性能、营养物质消化率、瘤胃发酵以及血浆生化指标的影响。选取18头湘中黑牛[平均体重(330±30)kg],采用单因素完全随机试验设计分为3组,每组6头,对照组饲喂基础饲粮,试验组在基础饲粮中分别添加120(组Ⅰ)、240g/kg酿酒酵母(组Ⅱ)。预试期为10d,正试期为30d。结果表明:1)饲粮中添加酿酒酵母对湘中黑牛平均日增重及料重比无显著影响(P0.05)。2)饲粮中添加酿酒酵母显著降低了粗蛋白质粪排放量(P0.05),对干物质、中性洗涤纤维和粗蛋白质消化率无显著影响(P0.05)。3)各组瘤胃液中氨态氮(NH3-N)以及挥发性脂肪酸(VFA)浓度均无显著差异(P0.05)。4)饲粮中添加240g/kg酿酒酵母显著降低了湘中黑牛血浆中总胆固醇浓度(P0.05)。结果提示,饲粮中添加240g/kg酿酒酵母能够降低湘中黑牛粗蛋白质粪排放量以及血浆中总胆固醇浓度,对减少肉牛养殖过程中氮排放、改善养殖环境以及促进肉牛健康养殖具有重要意义。

Effects of Saccharomyces cerevisiae on Nutrient Digestibility,Rumen Fermentation and Plasma Biochemical Parameters of Xiangzhong Black Beef

The objective of this trial was to explore the effects of different supplementation levels of Saccharomyces cerevisiae on growth performance,nutrient digestibility,rumen fermentation and plasma biochemical parameters of Xiangzhong black beef.The study was conducted as one-factor randomly block experimental design,eighteen Xiangzhong black beef [(330±30) kg] were blocked into 3 groups with 6 beef per group.Control group was supplemented with a basal diet,and experimental groups were supplemented with 120 and 240 g/kg Saccharomyces cerevisiae,respectively.The pre-test lasted for 10 d,and the test lasted for 30 d.The results showed as follows: 1) dietary Saccharomyces cerevisiae supplementation had no significant differences on average daily gain and feed to gain ratio (P>0.05).2) Dietary Saccharomyces cerevisiae supplementation significantly decreased fecal excretion of crude protein (P<0.05),but had no significant effects on digestibility of dry matter,neutral detergent fibre and crude protein (P>0.05).3) Ammonia nitrogen and volatile fatty acids concentrations were not significantly affected by Saccharomyces cerevisiae supplementation (P>0.05).4) Dietary supplementation of 240 g/kg Saccharomyces cerevisiae significantly decreased plasma total cholesterol concentration (P<0.05).The results indicate that dietary supplementation of 240 g/kg Saccharomyces cerevisiae can decrease fecal excretion of crude protein and plasma total cholesterol concentration,which play important roles in decreasing nitrogen emission,improving husbandry environment and promoting health of beef.