利用体外产气法研究植物精油对瘤胃体外发酵和甲烷生成的影响

Effects of essential oil on rumen fermentation and methanogenesis in vitro gas production

为探讨植物精油对瘤胃体外发酵的影响,采用体外产气法分析不同添加水平的茶树油、肉桂油和丁香油对瘤胃发酵模式、发酵产气量及动力学参数和瘤胃氮代谢的影响。与对照组相比结果表明:1)添加各剂量的茶树油和肉桂油对微生物蛋白(MCP)含量无显著影响,但氨氮(NH3-N)浓度均有降低趋势,其中添加300和1 500mg/L肉桂油显著降低了NH3-N浓度(P<0.05)。2)添加1 000mg/L的茶树油或1 500mg/L的肉桂油显著降低了总挥发性脂肪酸(TVFA)和丙酸浓度(P<0.05),而50和100mg/L茶树油处理组丁酸浓度显著升高(P<0.05),300和500mg/L的肉桂油处理组支链脂肪酸浓度显著升高(P<0.05)。3)添加100mg/L的茶树油和丁香油均可显著提高理论最大发酵产气量(b),并且所有植物精油添加组甲烷(CH4)体积分数均有降低。添加100mg/L的茶树油或100和300mg/L的肉桂油有助于改善瘤胃微生物发酵。

An in vitro cumulative gas production trial was conducted to study the effects of tea tree oil,cinnamon oil,and clove bud oil on subsequent 72 h rumen fermentation and methanogenesis at different dose.The results showed that,1） there were no effect on the production of microbial crude protein,but the concentration of ammonia N were decreased with added tea tree oil and cinnamon oil,especially when the cinnamon oil at the dose of 300 or 1 500 mg/L（P0.05）.2） the production of total volatile fatty acid（TVFA） and concentration of propionic acid were decreased by adding 1 000 mg/L tea tree oil or 1500 mg/L cinnamon oil.At dose of 50 and 100 mg/L,the tea tree oil increased the concentration of butyrate acid.The production of iso-butyrate and iso-valerate acid were increasing with 300 and 500 mg/L cinnamon oil.3） At 100 mg/L,tea tree oil and clove bud oil were significant different on the theory maximum gas production compared with the control groups.All treatments tended to decrease the methane concentration（P0.05）.In general,the tea tree oil at the level of 100 mg/L and cinnamon oil at the 100 and 300 mg/L may be allowed to manipulation of rumen microbial fermentation.