绿汁发酵液对柱花草青贮营养成分及品质的影响

试验旨在研究绿汁发酵液(previously fermented juice,PFJ)对柱花草青贮营养成分及品质的影响。以热研2号柱花草为原料进行青贮试验,设对照组(直接青贮)和试验Ⅰ、Ⅱ、Ⅲ、Ⅳ及Ⅴ组,各试验组PFJ添加比例为1%、2%、3%、4%和5%,30 d后测定柱花草青贮饲料主要营养成分含量及发酵品质。结果显示,与对照组相比,试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组粗蛋白质(CP)含量显著提高(P < 0.05),Ⅱ、Ⅲ、Ⅳ和Ⅴ组中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量均有不同程度的降低,Ⅱ、Ⅲ、Ⅳ、Ⅴ组柱花草青贮的饲料相对值(RFV)显著提高(P < 0.05)。添加PFJ试验组与对照组相比显著降低了青贮饲料的pH (P < 0.05),乙酸和丙酸含量均有不同程度的降低,乳酸含量显著提高(P < 0.05)。柱花草直接青贮品质较差,添加PFJ提高了饲料青贮质量评分等级。综上所述,添加PFJ可提高营养价值,明显改善柱花草青贮品质,PFJ添加量为4%时青贮效果最好。

Effects of Previously Fermented Juice on the Nutrient Composition and Quality of Stylo Silage

The experiment was carried out to investigate the effects of previously fermented juice (PFJ) on the nutrient composition and quality of stylo silage.The Stylosanthes guianensis Reyan No.2 were selected and there were six groups:Control group (to be silaged directly) and groups Ⅰ,Ⅱ,Ⅲ,Ⅳ and Ⅴ which were added with 1%,2%,3%,4% and 5% PFJ,respectively.All groups were stored for 30 days,and then the chemical composition and fermentation quality of the stylo silage were analyzed.The results showed that compared to control group,CP contents of groups Ⅰ,Ⅱ,Ⅲ and Ⅳ were significantly increased (P < 0.05) and NDF,ADF contents of groups Ⅱ,Ⅲ Ⅳ and Ⅴ were decreased in different degree.The RFV of groups Ⅱ,Ⅲ,Ⅳ and Ⅴ were significantly increased (P < 0.05).Compared with control group,the pH of the PFJ treatment groups were significantly decreased (P < 0.05),meanwhile acetic acid and propionic acid were decreased in different degree.Lactic acid contents were significantly increased (P < 0.05).The quality of stylo silage was poorer when it was silaged directly and the Flieg grades could be improved adding PFJ.In conclusion,adding PFJ could improve the fermentation quality and nutrient value of stylo silage and 4% PFJ was the proper application rate.