添加剂和水分对光叶紫花苕青贮品质的影响

2种含水量(鲜草、晾晒3 h)的光叶紫花苕,分别添加对照(CK)、3和6 L/t的甲酸铵(ATlo和AThi)、1.0×10⁵ cfu/g鲜草的乳酸菌、以及添加3和6 L/t由苯甲酸钠、丙酸钠、亚硝酸钠和六亚甲基四胺组成的混合抗菌剂(AMlo和AMhi)。结果表明,添加剂对光叶紫花苕的青贮发酵品质有极显著影响(P＜0.01),各种添加剂均不同程度的提升了光叶紫花苕青贮饲料的发酵品质;除pH值外,含水量对光叶紫花苕青贮发酵品质有极显著影响(P＜0.01),低水分的牧草发酵品质优于高水分的牧草;添加剂和含水量对青贮发酵品质有极显著的交互作用(P＜0.01)。综合各项指标,在高水分牧草中以添加6 L/t AT和3 L/t AM后牧草的发酵品质最好;在低含水量的牧草中,各种添加剂间效果相近,但均优于对照。结果表明,降低光叶紫花苕的含水量并选择合适的添加剂可调制优质青贮。

Effects of additive and moisture content on fermentation quality of smooth vetch silage

The fermentation quality of smooth vetch (Vicia villosa var.) silage kept for 60 days were investigated using smooth vetch with high (fresh) and low (wilt for 3 hours) moisture content. Ammonium formate (3, 6 L/t), lactic acid bacteria (1.0×10⁵ cfu/g FW), antimicrobial mixture including sodium benzoate, sodium propionate, sodium nitrite, and hexamethylenetetramine (3, 6 L/t) were added separately at ensiling but the CK had no additives. The results indicated that the fermentation quality of smooth vetch silage with high and low moisture contents were highly significantly (P＜0.01) affected by additives, but positive performances depended on the levels. The moisture content played a highly significantly positive role in improving the fermentation quality of smooth vetch silage except for the pH value (P＜0.01). The group with low moisture content performed better than the one with high moisture content. Highly significant (P＜0.01) interactions occurred between the two factors (additives and moisture content). Overall, in the high moisture content silage group, the treatments with added ammonium formate (6 L/t) and antimicrobial mixture (3 L/t) showed the best performance in fermentation quality of smooth vetch silage. In the high moisture content silage group, all treatments showed positive effects compared with the CK but without significant differences. To make silage with high quality, reducing the moisture content and adding suitable additives before ensiling are suggested.