黄牛瘤胃的低甲烷化诱导及其菌群演变规律研究

Rumen produced methane is not only a super-greenhouse gases but also the main reason of energy loss in rumen fermentation. Regulation of rumen microbial flora and reduction of methane production have an important significance for mitigating global warming and improving utilization of rumen feed. In general, control methods of rumen produced methane, which aimed at adult ruminant animal, have no significant effect. Through the combination of rumen microflora of low-methanation and natural products of reducing methane, we will make of composite induction agents. By inoculating Guangfeng yellow cattle in vivo with composite induction agents, the rumen microbial communities are continuously induced and evolved toward low-methanation until rumen microflora of low-methanation is built. According to changes of rumen microflora and characteristics of rumen fermentation under the induction of composite induction agents, low-methanation growth model for ruminant animal which provided a theoretical basis for application and research to methane emissions reduction, is eventually established.

瘤胃产生的甲烷不仅是超强温室气体，同时也是造成瘤胃发酵能量损失的主要原因。调控瘤胃微生物菌群，降低甲烷产生，对于缓解气候变暖，提高瘤胃的饲料利用率具有重要意义。目前瘤胃甲烷调控技术都是针对成年反刍动物的后调控，普遍存在着调控效果不显著的问题。本项目将选育的低甲烷活性瘤胃原籍菌群与降甲烷天然产物结合，制成复合诱导剂，接入幼龄广丰黄牛体内，对瘤胃进行连续诱导，使瘤胃微生物群落沿着低甲烷化方向演变，在成年牛体内构建起低甲烷活性瘤胃菌群。通过对诱导中瘤胃菌群变化规律和发酵特性的分析，最终建立低甲烷活性瘤胃菌群发育模型，为反刍动物甲烷减排适用技术的研发和应用提供理论依据。

瘤胃产生的甲烷不仅是超强温室气体，同时也是造成瘤胃发酵能量损失的主要原因。调控瘤胃微生物菌群，降低甲烷产生，对于缓解气候变暖，提高瘤胃的饲料利用率具有重要意义。本项目针对目前瘤胃甲烷调控效果不显著的问题，开展了瘤胃复合诱导剂研制、黄牛瘤胃低甲烷化诱导、瘤胃发酵性能和微生物菌群比较分析等研究工作。研究结果表明：1）诱导剂作用下形成的瘤胃微生态系统甲烷排放量下降了28.15%，MCP提高了26.71%，乙酸/丙酸降低了37.78%，呈现典型的低甲烷化-丙酸型发酵特征，即使停止使用诱导剂，这种特征仍能较长时间保持；2）诱导剂显著提高了瘤胃细菌的多样性、丰富度和均匀度，改善了细菌群落结构，由诱导剂诱导构建的瘤胃细菌群落结构更为复杂稳定，功能得到优化；3）诱导剂大大降低了瘤胃产甲烷菌的多样性、丰富度和均匀度，改变了产甲烷菌群落结构，其产甲烷功能被弱化到合理水平；4）丰富的细菌和简化的产甲烷菌是诱导剂作用下形成的瘤胃微生物群落的鲜明特征，这奠定了低甲烷化-丙酸型瘤胃发酵系统的微生物学基础。