中文摘要：

利用体外批次培养技术，分别以羊草、玉米和淀粉为底物，研究了反刍兽新月形单胞菌L9菌株及其与酵母联用对瘤胃微生物发酵的影响。结果显示，以羊草为底物时，添加酵母可显著提高乙酸、丙酸、丁酸、戊酸、异戊酸和TVFA浓度（P〈0．05），降低乳酸浓度（P〈0．05），有降低乙丙比值的趋势（P=0．082），但对异丁酸及pH值无显著影响（P〉0．10），添加1．9菌可显著提高pH值、乙酸、丙酸、丁酸、异戊酸和TVFA浓度（P％0．05），降低乳酸浓度和乙丙比值（P〈0．05），但对异丁酸及戊酸浓度无显著影响（P〉0．10），在影响pH值、丙酸、丁酸、异丁酸、异戊酸、TVFA浓度及乙丙比值方面，酵母与L9菌株间无显著的互作关系（P〉0．10）；在降低乳酸及戊酸浓度方面，酵母与L9菌株之间有显著的互作作用（P〈0．05），在影响pH值及乙酸产量方面，酵母与L9菌之间有互作效应趋势。以玉米为底物时，添加酵母可显著提高pH值、乙酸、丙酸、丁酸、异戊酸和TVFA浓度（P〈0．05），降低乳酸浓度和乙丙比值（P〈0．05），有提高戊酸浓度的趋势（P=0．082），但对异丁酸无显著影响（P〉0．10），添加L9菌可显著提高pH值、乙酸、丙酸、丁酸、戊酸、异戊酸和TVFA浓度（P〈0．05），降低乳酸浓度和乙丙比值（P〈0．05），但对异丁酸浓度无显著影响（P〉0．10），在影响pH值、乳酸、乙酸、丙酸、丁酸、异戊酸、TVFA浓度及乙丙比值方面，酵母与L9菌株间有显著的互作关系（P〈0．05）；在影响异丁酸及戊酸浓度方面，酵母与L9菌株之间无显著的互作作用（P〉0．10）。以淀粉为底物时，添加酵母可显著提高pH值、乙酸、丙酸、丁酸、异戊酸和TVFA浓度（P〈0．05），降低乳酸浓度（P〈0．05），但对戊酸、异丁酸浓度和乙丙比值无显著影响（P〉0．10），添加L9菌?

英文摘要：

In vitro combination with batch culture techniques were used to investigate the effect of S. ruminantium alone and in yeast cultures on rumen bacterial fermentation. When Leymus chinensis was used as a substrate, yeast culture addition increased the acetate, propionate, butyrate, valeric acid, isovaleric acid and TVFA contents （P~0.05）, and reduced lactic acid content, but had no significant effects on pH value, isobutyrate or ratio of acetate to propionate （P〈0.05）. The ratio of acetate to propionate and the lactate concentration were reduced （P〈0.05）, and acetate, propionate, n-butyrate, isobutyrate, isovaleric acid, TVFA content and pH value were improved by S. ruminantium supplementation （P〈0.05）. There was no significant interaction between pH value, acetate, propionate, butyrate, isovaleric acid or TVFA content between S. ruminantium and yeast cultures （P〈0.10）. When maize was used as a substrate, live-yeast culture addition increased pH value, acetate, propionate, n-butyrate, isobutyrate, isovaleric acid and TVFA content （P〈0. 05）, and re- duced lactate concentration and the ratio of acetate to propionate （P〈0.05）, but there was no significant effect on isobutyrate content （P〉0.10）. pH value, acetate, propionate, butyrate, isovaleric acid and TVFA content were improved by S. ruminantium, and S. ruminantium supplements lowered lactate content and the ratio of acetate to propionate （P〈0.05）. There was a significant interaction effect on pH value, lactate, acetate, pro- pionate butyrate, TVFA content and the ratio of acetate to propionate between S. ruminantium L9 and yeast cultures （P〈0.05）. When starch was used as a substrate, S. ruminantium had an increase in pH value and acetate, propionate, butyrate and TVFA content （P〈0.05）, but a decrease in lactate concentration and the ratio of acetate to propionate （P〈0.05）. Yeast culture supplement increased pH value and acetate, propionate, butyrate and TVFA content （P〈0. 05）, but had no