添加乳酸菌制剂和糖蜜对箭？Q豌豆和苇状羊茅混合青贮发酵品质的影响

[目的]本文旨在评价添加乳酸菌和糖蜜对箭？Q豌豆和苇状羊茅混合青贮发酵品质的改善效果。[方法]将处于抽穗初期的苇状羊茅和处于结荚期的箭？Q豌豆以7：3（鲜质量比）混合青贮，并单独或组合添加乳酸菌制剂（106 CFU？g-1）和糖蜜（4%），分别在青贮后的第7、24、45和60天开窖取样，分析混合青贮饲料发酵品质的动态变化。[结果]与对照组相比，单独添加乳酸菌制剂对混合青贮发酵品质的改善效果不明显，而糖蜜或糖蜜+乳酸菌制剂显著提高了乳酸含量（P<0.05），降低了pH值和氨态氮含量，其中糖蜜+乳酸菌制剂组乳酸含量在青贮第7天已显著高于其他各组（P<0.05），并在整个青贮过程中保持最高水平。青贮过程中，各处理组仅检测到微量丙酸和丁酸，并始终显著低于对照组（P<0.05）。[结论]添加糖蜜+乳酸菌提高了青贮饲料的发酵品质，可确保青贮饲料长期保存。
[Objectives] The aim of this study was to assess the effect of adding inoculants or/and molasses on the dynamics of fermentation characteristics of mixed silages of common vetch and tall fescue during ensiling. [Methods] Mixture of tall fescue and common vetch(7:3) were ensiled and treated with distilled water(control),inoculant(LAB,2 mL？kg-1),molasses(M,4%) and inoculant+molasses(M+LAB) prior to ensiling. [Results] Compared with the control,there was no significant effect on improving fermentation quality of mixed silages with inoculant.The addition of M and M+LAB significantly(P<0.05) increased lactic acid contents and significantly(P<0.05) decreased pH and ammonia content as compared with control. The lactic acid content in M+LAB began to be higher than other treatments on day 7 of ensiling,and remained the highest value among treatments until the end of ensiling. The concentrations of butyric and propionic acid in silages treated with inoculants or/and molasses were significantly(P<0.05) lower than those of control during the ensiling. [Conclusions] The inoculant+molasses treatment improved the fermentation quality and ensured the long-term preservation of mixed silages