添加不同发酵菌剂的完全混合发酵日粮对延边黄牛瘤胃微生物体外发酵特性的影响

试验主要研究添加不同发酵菌剂的完全混合发酵日粮（total mixed fermentation，TMF）对延边黄牛瘤胃微生物体外发酵特性的影响。试验分为CON组（对照组）、T1组（添加NFK）、T2组（添加RJ）和T3组（添加CT-10），每组3个重复。各试验组以TMR为发酵底物，分别接种对应发酵菌种，装入发酵袋内，在室温条件下密封发酵一周后开袋，尼龙袋法测定瘤胃干物质消失率，产气量法检测瘤胃发酵特性。结果显示，随着发酵时间的延长，不同的发酵菌剂可在不同程度上影响瘤胃干物质消失率、pH、产气量、气体成分、挥发性脂肪酸和微生物蛋白含量。在8 h时，T1和T3组瘤胃干物质消失率显著高于对照组（P < 0.05），而其他时间段差异不显著（P > 0.05）；随着培养时间的延长，各组培养液pH逐渐下降，体外培养1 h，T2组pH显著低于对照组（P < 0.05）；各组挥发性脂肪酸（VFAs）含量随着培养时间的增加呈现上升趋势；体外培养12 h时，T3组氨态氮（NH₃-N）含量最高，为5.79 mg/dL，而T2组最低，与对照组差异不显著（P > 0.05）；微生物菌体蛋白（MCP）呈先升高再降低再升高趋势，培养1、3、12 h时，试验组MCP含量均显著低于对照组（P < 0.05），而培养6和9 h，各组间无显著性差异（P > 0.05）；在培养1 h时，不同的发酵菌剂对产气量没有显著影响（P > 0.05）；在培养9和12 h时，对照组产气量最高，且显著高于试验组（P < 0.05）；各组H₂产量变化趋势一致，都是呈现上下波动状态；CH₄和CO₂含量随着培养时间的延长而呈现上升的趋势，且不同发酵菌剂对其影响显著（P < 0.05）。综上所述，T3组（添加CT-10）延边黄牛瘤胃干物质降解效果较好，CT-10菌发酵效果与T2组（添加RJ）发酵效果相当，且可有效改善延边黄牛的瘤胃发酵特性，因此CT-10菌可应用于延边黄牛TMF的调制中。

Effects of TMF with Different Fermentation Agents on in vitro Fermentation Characteristics of Rumen Microbes in Yanbian Yellow Cattle

This experiment was conducted to investigate the effect of TMF with different fermentation agents on in vitro fermentation characteristics of rumen microorganisms in Yanbian Yellow cattle.The experiment was divided into four experimental groups:CON group (control group),T1 group (adding NFK),T2 group (adding RJ) and T3 group (adding CT-10) with three replicates per group.The TMR with different fermentation agents was loaded into the fermentation bag and sealed at room temperature for 7 d.And then,the ruminal DM disappearance rate was determined by Nylon Bag Technique and the fermentation characteristics were measured by in vitro gas production technique.The results showed that:With the prolonging of fermentation time,the different fermentation agents could significantly affect the rumen DM disappearance rate,pH,gas production,gas composition,volatile fatty acid (VFAs) and microbial protein content (MCP) in different extent.At 8 h,compared with the control group,the rumen DM disappearance rate of T1 and T3 groups were significantly increased (P < 0.05),but there was no significant difference among the groups at the other time periods (P > 0.05).The pH of culture medium in each experimental group decreased gradually,and the pH in T2 group was significantly lower than that in control group when cultivated for 1 h (P < 0.05).The content of VFAs in each experimental group showed an upward trend.At 12 h,the content of NH₃-N in T3 group was highest (5.79 mg/dL),while T2 group was lower than the control group (P > 0.05).The content of MCP increased first,then decreased and then increased.At 1,3 and 12 h,the MCP contents of the experimental groups were significantly lower than that in control group (P < 0.05),but there was no significant difference at 6 and 9 h (P > 0.05).After 1 h cultivation,different fermentation agents had no significant effect on gas production (P > 0.05).At 9 and 12 h,the control group had the highest gas production,and significantly higher than experimental groups (P < 0.05).The changes of H₂ production in group tended to be consistent,showing the fluctuation state.With the prolongation of incubation time,the content of CH₄ and CO₂ showed a rising trend and were significantly affected by different fermentation agents (P < 0.05).In conclusion,we found that the DM disappearance rate of T3 group was higher,and the ferment effect of CT-10 was equivalent with T2 group adding RJ which could efficiently improve the rumen fermentation characteristics,so CT-10 could be used into IMF of Yanbian Yellow cattle.