添加乳酸菌和糖蜜对全株构树和稻草混合青贮的影响

以全株构树和稻草为原料,按照鲜重质量比10∶0(A组)、9∶1(B组)、8∶2(C组)、7∶3(D组)混合调制青贮饲料。各混合比例设无添加剂(CK)、糖蜜组(T)、乳酸菌组(GLP5)及糖蜜+乳酸菌组(T+GLP5),青贮60 d分析发酵品质和营养成分。结果表明:各混合比例糖蜜添加组(T、T+GLP5)的pH值和氨态氮/总氮与对照组相比显著降低(P<0.05),乳酸含量显著升高(P<0.05),GLP5与CK处理相比,pH值和氨态氮/总氮显著降低(P<0.05);B处理组乳酸和乙酸含量显著高于C、D组(P<0.05)。各混合比例添加剂处理组中性洗涤纤维、酸性洗涤纤维和半纤维素均降低,A、B及D组T、T+GLP5处理中性洗涤纤维、半纤维素显著降低(P<0.05),C组T处理中性洗涤纤维、酸性洗涤纤维和半纤维素含量显著降低(P<0.05)。综上所述,全株构树与稻草混合青贮时选用糖蜜添加组(T、T+GLP5),同时选用9∶1的混合比例较适宜。

The effects of adding lactic acid bacteria and molasses on fermentation of Broussonetia papyrifera and rice straw mixed silage

This research evaluated fermentation quality of silage made from Broussonetia papyrifera and rice straw mixed in various proportions, with or without additives. B. papyrifera and rice straw were mixed in ratios by fresh weight of 10∶0 (Group A), 9∶1 (Group B), 8∶2 (Group C), and 7∶3 (Group D). The fermentation quality and nutritional quality were analyzed after 60 days fermentation with no additive (CK), or addition of molasses (T), lactobacillus (GLP5), or molasses and lactobacillus (T+GLP5). Compared with the CK silages, the pH value and ammonia nitrogen∶total nitrogen ratio of the T and, T+GLP5 silages were significantly decreased (P<0.05), and the lactic acid content was significantly increased (P<0.05). The GLP5 treatment significantly lowered (P<0.05) the pH and ammonia nitrogen∶total nitrogen ratio compared to CK, but less so than the T treatments. As expected, neutral and acid detergent fiber and cellulose and hemicellulose concentrations increased and crude protein fell with increasing proportion of rice straw. In general, for a given proportion of rice straw, additive treatments ranked CK>GLP5>T>T+GLP5 for fiber and cellulose levels and the opposite for crude protein, although some interactions between mixture proportion and additive occurred. In summary, the T and T+GLP5 silages with added molasses and a 9∶1 mixing ratio of B. papyrifera and rice straw are optimal for silage making with these materials.