不同混合比例对杂交狼尾草与桑叶青贮品质的影响

Effects of Different Mixing Ratios on Silage Quality of Hybrid Pennisetum and Mulberry Leaves

本试验将不同比例的杂交狼尾草和桑叶混合进行青贮,研究二者的混合比例对青贮品质的影响。设计3个杂交狼尾草与桑叶的混合比例,按原料鲜重计算分别为100∶0(P100)、70∶30(PM73)、50∶50(PM55),在青贮3、7、14、30 d后的分析青贮品质,每个混合比例的不同青贮时间均设3个重复。结果显示:随着青贮时间的增加,青贮饲料的乳酸、氨态氮(NH3-N)含量逐渐增加,pH、水溶性碳水化合物(WSC)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量逐渐降低,乳酸菌、酵母菌数量均先增加后减少。随着桑叶添加比例的增加,青贮饲料的pH、乳酸、粗蛋白质(CP)、真蛋白质(TP)含量显著增加(P<0.05),NDF、ADF含量显著降低(P<0.05)。青贮3、14、30 d时,PM55处理的乙酸含量显著高于PM73和P100处理(P<0.05)。青贮7、30 d时,随桑叶添加比例的增加,酵母菌数量显著降低(P<0.05)。青贮3、7、14 d时,PM55、PM73处理的乳酸菌数量显著高于P100处理(P<0.05)。青贮30 d时,PM55处理的WSC、乳酸含量及TP/CP比值最高。综上所述,以50%杂交狼尾草+50%桑叶混合青贮时青贮饲料的青贮品质较高。

In this experiment,the effects of mixing ratio of hybrid Pennisetum and mulberry leaves on silage quality was investigated by mixing silage at different mixing ratios of both.Three hybrid Pennisetum and mul⁃berry leaves mixing ratios were used in the experiment,they were 100∶0(P100),70∶30(PM73)and 50∶50(PM55)according to raw material fresh weight.The silage quality was analyzed at 3,7,14 and 30 days after silage,and three replicates were set for different silage time for each mixing ratio.The results showed that the lactic acid and ammonia nitrogen(NH3⁃N)contents of silage gradually increased,the pH,and the contents of soluble carbohydrate(WSC),neutral detergent fiber(NDF)and acid detergent fiber(ADF)contents gradu⁃ally decreased,and the lactic acid bacteria and yeast counts increased firstly and then decreased as the silage time increasing.As the adding ratio of mulberry leaves increasing,the pH,lactic acid,crude protein(CP)and true protein(TP)contents increased significantly(P<0.05),while the NDF and ADF contents decreased significantly(P<0.05).For 3,14 and 30 days of ensiling,the acetic acid content of PM55 treatment was sig⁃nificantly higher than that of PM73 and P100 treatments(P<0.05).For 7 and 30 days of ensiling,the yeast count significantly decreased with the increase of mulberry leaves adding ratio(P<0.05).For 3,7 and 14 days of ensiling,the lactic acid bacteria count of PM73 and PM55 treatments was significantly higher than that of P100 treatment(P<0.05).The PM55 treatment had the highest WSC,lactic acid contents and TP/CP ratio at 30 days of ensiling.In conclusion,the silage mixed with 50%hybrid Pennisetum+50%mulberry leaves has the better silage quality.