【摘要】 本研究利用体外产气法,探究饲粮中分别添加1%、2%、3%及4%(干物质基础)的硬核油对瘤胃体外发酵24 h产气参数、发酵参数及脂肪酸组成的影响,旨在确定硬核油在瘤胃发酵中的最适添加水平。结果表明:1)饲粮中添加硬核油对24 h产气量、理论最大产气量及产气速率无显著影响(P>0.05)。2)氨氮(P=0.044)、总挥发性脂肪酸(P<0.001)、乙酸(P<0.001)、丙酸(P=0.047)及丁酸浓度(P=0.017)随硬核油添加水平的增加呈二次曲线升高,且总挥发性脂肪酸及乙酸浓度在1%、2%及3%组显著高于对照组及4%组(P<0.05);p H、微生物蛋白浓度、干物质降解率、中性洗涤纤维降解率及酸性洗涤纤维降解率未受硬核油添加的影响(P>0.05)。3)饱和脂肪酸的含量随硬核油添加水平的增加呈线性(P=0.008)及二次(P=0.028)降低,其中C18∶0的含量也呈线性降低(P=0.030);不饱和脂肪酸的含量随硬核油添加水平的增加呈线性(P=0.008)及二次(P=0.028)升高,其中t9-C18∶1含量呈线性(P=0.002)、t11-C18∶1含量呈二次(P<0.001)、c9-C18∶1含量呈线性(P=0.028)和二次(P=0.005)升高,且t9-C18∶1及c9-C18∶1含量均在3%添加水平下出现最大值。在本试验条件下,1%、2%及3%添加水平的硬核油可提高瘤胃体外发酵不饱和脂肪酸含量,同时增加挥发性脂肪酸的浓度,3%添加水平效果最佳。更多还原

【Abstract】 In order to find the optimal supplemental level of Scleropyrum wallichianum oil,the effects of adding1 %,2 %,3 % or 4 %(dry matter basis) of Scleropyrum wallichianum oil in diet on 24 h rumen fermentation parameters,gas production parameters and composition of fatty acids were investigated using in vitro gas production method.The results showed as follows:1) there were no significant effects of adding Scleropyrum wallichianum oil in diet on 24 h gas production,theoretical maximum gas production and the rate of gas production(P > 0.05).2) The concentrations of ammonia nitrogen(P = 0.044),total volatile fatty acid(P < 0.001),acetate(P < 0.001),propionate(P = 0.047) and butyrate(P = 0.017) quadratically increased as the level of Scleropyrum wallichianum oil increased,besides,the concentrations of total volatile fatty acid and acetate of 1 %,2 %and 3 % groups were significantly higher than those in control group and 4 % group(P < 0.05); there were no significant effects of adding Scleropyrum wallichianum oil on p H,microbe protein concentration,dry matter degradation rate,neutral detergent fiber degradation rate and acid detergent fiber degradation rate(P > 0.05).3)The content of saturated fatty acid was linearly(P = 0.008) and quadratically decreased(P = 0.028) as the level of Scleropyrum wallichianum oil increased,and C18∶ 0 content was linearly decreased(P = 0.030),too; the content of unsaturated fatty acid was linearly(P = 0.008) and quadratically increased(P = 0.028) as the level of Scleropyrum wallichianum oil increased,t9-C18∶ 1 content was linearly(P = 0.002),t11-C18∶ 1 content was quadratically(P < 0.001) and c9-C18∶ 1 was linearly(P = 0.028) and quadratically increased(P = 0.005),and t9-C18∶ 1 and c9-C18∶ 1 reached maximum values under the adding level of 3 %.Under the conditions of the present study,the levels of 1 %,2 % and 3 % Scleropyrum wallichianum oil can increase the contents of unsaturated fatty acids and the concentrations of volatile fatty acids,and the level of 3 % has the best effect.更多还原