不同添加剂处理紫穗槐青贮对延边黄牛瘤胃体外发酵参数及干物质降解率的影响

Effect of different additive treatments of Amorpha fruticosa silage on rumen fermentation parameters and dry matter degradation rate of Yanbian cattle in vitro

试验旨在探讨不同添加剂处理紫穗槐青贮对延边黄牛瘤胃体外发酵参数及干物质降解率的影响。选用3头健康、平均体重(455.82±20.32)kg、安装永久性瘤胃瘘管的延边黄牛提供瘤胃液。试验共设5组,分别为添加等量蒸馏水青贮组(CK组)、乳酸菌组(LAB组)、糖蜜组(M组)、乳酸菌加糖蜜组(LAB-M组)和纤维素酶组(CE组),每组3个重复。避光青贮60 d,计算紫穗槐青贮的营养成分含量。体外发酵48 h,测定体外发酵指标总产气量、pH值、氨态氮(NH3-N)、挥发性脂肪酸含量,计算干物质降解率。结果显示:CE组青贮紫穗槐酸性洗涤纤维和中性洗涤纤维含量显著高于其他组(P<0.05)。发酵48 h时,各试验组体外发酵pH值均显著低于CK组(P<0.05)。发酵24 h和48 h时,各个试验组体外发酵产气量均显著高于CK组(P<0.05)。发酵24 h和48 h时,试验组体外发酵的NH3-N含量均显著低于CK组(P<0.05)。发酵48 h后,试验组体外发酵的乙酸、丙酸、总挥发性脂肪酸含量均显著高于CK组(P<0.05),丁酸含量均显著低于CK组(P<0.05)。各个时间点干物质降解率排序为:LAB-M组>CE组>M组>LAB组>CK组。研究表明,添加乳酸菌、糖蜜和纤维素酶处理紫穗槐对延边黄牛瘤胃体外发酵参数及干物质降解率具有不同程度的改善作用,其中添加乳酸菌和糖蜜混合青贮紫穗槐的效果较好。

The experiment was conducted to investigate the effect of different additive treatments of Amorpha fruticosa silage on rumen fermentation parameters and dry matter degradation rate of Yanbian cattle in vitro.Three healthy Yanbian cattle with an average weight of(455.82±20.32)kg and permanent rumen fistulas were selected to provide rumen fluid in the experiment.A total of five groups were set up,including silage group(CK group),lactic acid bacteria group(LAB group),molasses group(M group),lactic acid bacteria molasses group(LAB-M group)and cellulase group(CE group),with three replicates in each group.The nutrient content of Amorpha fruticoa silage was calculated after 60 d of dark silage.After 48 h in vitro fermentation,total gas production,pH value,content of ammonia nitrogen(NH3-N)and volatile fatty acids were determined,and dry matter degradation rate was calculated.The results showed that the content of acid detergent fiber and neutral detergent fiber in CE group were significantly higher than those in other groups(P<0.05).After48 h fermentation,the pH value of in vitro fermentation in experimental groups was significantly lower than that in CK group(P<0.05).After 24 h and 48 h fermentation,gas production in vitro fermentation of experimental groups was significantly higher than that of CK group(P<0.05).After 24 h and 48 h fermentation,NH3-N content of in vitro fermentation in four experimental groups was significantly lower than that in CK group(P<0.05).After 48 h fermentation,the content of acetic acid,propionic acid and total volatile fatty acid in vitro fermentation of experimental groups were significantly higher than those of CK group(P<0.05),and the content of butyric acid was significantly lower than that of CK group(P<0.05).The dry matter degradation rate at each time point was ranked as follows:LAB-M group>CE group>M group>LAB group>CK group.The study indicates that adding lactic acid bacteria,molasses and cellulase additive silage can improve in vitro rumen fermentation parameters and dry matter degradation rate of Yanbian cattle to varying degrees,and the LABM group adding lactic acid bacteria and molasses mixed silage has better effect.