乳酸菌和纤维素酶对直穗鹅观草青贮的改善效果

本试验以直穗鹅观草(Roegneria turczaninovii)为材料，研究了乳酸菌和纤维素酶单独添加或以不同比例混合添加对鹅观草青贮发酵品质和营养价值的改善效果。处于抽穗期的直穗鹅观草经刈割切短后，分别添加纤维素酶0.06 g·kg-1 (CF)，乳酸菌0.01 g·kg-1 (LD1)、0.02 g·kg-1 (LD2)，纤维素酶+乳酸菌(0.06+0.01) g·kg-1 (CF+LD1)和(0.06+0.02) g·kg-1 (CF+LD2)，并设置无添加剂组为对照(CK)，每个处理3个重复。真空密封条件下贮藏90 d后，所有添加剂处理组pH值、丙酸、丁酸和氨态氮含量均显著低于对照组（P<0.05），乳酸、乙酸、粗蛋白（CP）和可溶性糖水化合物(WSC)含量均显著高于对照组（P<0.05），且CF、CF+LD1和CF+LD2处理的中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）含量显著低于对照（P<0.05）。由此可见，添加乳酸菌和纤维素酶使直穗鹅观草青贮饲料的发酵品质和营养价值均得到了改善，且以混合添加0.06 g·kg-1的纤维素酶和0.02 g·kg-1的乳酸菌制剂的效果最好。

Effects of lactic acid bacteria inoculants and enzymes on Roegneria turczaninovii silages

The effects of lactic acid bacteria inoculants and cellulose enzymes on the fermentation quality and chemical compositions of Roegneria turczaninovii silages were assessed in this study. R.turczaninovii at heading stage was harvested and cut into 2 cm, then treated with 0.06 g·kg-1 enzymes (CF), 0.01 g·kg-1 lactic acid bacteria inoculants (LD1), 0.02 g·kg-1 lactic acid bacteria inoculants (LD2), (0.06+0.01) g·kg-1 lactic acid bacteria inoculants and cellulose enzymes (CF+LD1), (0.06+0.02) g·kg-1 lactic acid bacteria inoculants and cellulose enzymes (CF+LD2), respectively, and there was no additive (CK). Eath treatment had three replications. After 90 days of conservation, the fermentation quality of R.turczaninovii silages was improved by the addition of bacteria and enzyme alone or together due to the lower pH value, butyric acid and NH3 N content (P<0.05) and higher lactic acid, acetic acid content (P<0.05) in all treated silages than CK. The crude protein (CP) and water soluble carbohydrate (WSC) content in treated silage was higher than CK (P<0.05). The CF, CF+LD1 and CF+LD2 had lower content of NDF and ADF than CK (P<0.05). The nutrition value of the silages was improved. The effect of CF+LD2 had the best effect both on fermentation quality and chemical compositions.