中文摘要：

利用体外产气量法研究绞股蓝皂甙对山羊瘤胃微生物体外甲烷产量及发酵特性的影响。试验包括2个部分,试验一研究了绞股蓝皂甙对瘤胃微生物甲烷产量及发酵特性的影响,试验二分析绞股蓝皂甙对瘤胃微生物发酵动力学参数的影响。试验以0.42 g羊草＋0.126 g玉米＋0.054 g豆粕为发酵底物,60 mL培养基中的绞股蓝皂甙添加量分别为0（对照）,5,10,20和40 mg,发酵24 h。与对照组比较,发酵8 h,各处理组甲烷浓度显著下降（P〈0.05）,分别下降30.20%,43.49%,44.67%和75.8%;12 h,20 mg组显著下降（P〈0.05）,40 mg组极显著下降（P〈0.01）,处理组甲烷浓度分别下降6.97%,9.63%,18.90%和61.82%;24 h,10 mg组显著下降（P〈0.05）,40 mg组极显著下降（P〈0.01）,处理组甲烷浓度分别下降2.34%,9.39%,6.90%和20.73%,甲烷浓度与皂甙剂量之间有极显著的线性效应（P〈0.01）。10 mg组的氢利用率极显著低于对照组,其他试验组无显著变化。10 mg组显著提高了TVFA及乙酸、丙酸、异丁酸、戊酸、异戊酸和支链脂肪酸浓度（P〈0.05）,40 mg组丁酸的浓度极显著下降（P〈0.01）。10 mg组和20 mg组乙丙比显著高于对照组（P〈0.05）。随着皂甙剂量增加,乙酸、丁酸、异丁酸、戊酸、异戊酸、支链脂肪酸、总挥发性脂肪酸浓度及乙丙比呈显著或极显著的二次方效应,丁酸同时具有极显著的线性效应。处理组原虫数量显著（P〈0.05）或极显著下降（P〈0.01）（40 mg组）,且与皂甙剂量间存在极显著的线性和二次方效应（P〈0.01）。微生物蛋白含量没有显著变化,但呈上升趋势。10 mg组和40 mg组的氨态氮浓度显著升高（P〈0.05）,氨态氮浓度与皂甙剂量之间有显著的线性效应（P〈0.05）。高剂量绞股蓝皂甙降低了微生物发酵的理论与实际产气量,并呈显著的线性和二次方效应,产气速率与皂甙剂量之间有着显著的线性效应。以上结果表?

英文摘要：

Effects of gypenoside on ruminal fermentation were investigated by an in vitro gas technique on mixed rumen microorganisms collected from goats.Experiment 1 was conducted to assess effects on methane production and fermentation characteristics of rumen microorganisms.Experiment 2 was done to assay effects on fermentation kinetic parameters.The diet consisted of Leymus chinensis 0.42 g,ground corn grain 0.126 g and soybean meal 0.054 g（1 mm screen）as substrates in each fermentation vessel.Five different doses were used for each compound（0,5,10,20 and 40 mg/60 mL of the total culture medium）.Compared with the control,during an 8 h fermentation,methane concentrations were reduced by 30.20%,43.49%,44.67% and 75.8% respectively after gypenoside addition（P0.05）.During a 12 h fermentation,gypenoside reduced methane concentration by 6.97%,9.63%,18.90%（P0.05） and 61.82%（P0.01） respectively at the four gypenoside concentrations.During a 24 h fermentation,methane concentration decreased by 2.34%,9.39%,6.90% and 20.73% after gypenoside treatment.A significant linear pattern was observed between methane production and gypenoside dosage（P0.01）.The hydrogen utilization was lower than the control at the 10 mg level（P0.01）.The TVFA（total volatility fatty acid）,acetate,propionate,isobutyrate acids,valerat,isovalerate and BCP concentrations were increased by the gypenoside treatments at the 10 mg level（P0.05） while butyrate was reduced by gypenoside treatment at 40 mg（P0.05）.The acetate to propionate ratio increased significantly with 10 mg and 20 mg of gypenoside（P0.05）.There was a significant quadratic pattern for acetate,butyrate,isobutyrate,valerate,isovalerate,BCP,TVFA and acetate to propionate ratio and TVFA concentration with the increasing gypenoside dose（P0.05 or P0.01）.There was also a linear pattern for butyrate（P0.01）.Relative to the control,the protozoa counts of treatment groups were significantly reduced by gypenoside addition（P0.05 or P0.01）,and there were line