Chemical, physical and biological changes of white oat ensiled with different additives

SUMMARY This study evaluated the addition of inoculants on the aerobic stability, nutritional value, and fermentation and microbiological profiles of white oat silages (Avena sativa L.). The trial was carried out in a completely randomized design with three treatments and six replicates. The treatments consisted of three ensiling approaches: oat (O); oat with homofermentative bacterial inoculant (OB); and oat with bacterial-enzymatic inoculant (OBE). The aerobic stability was 9 days for silage O and 14 days for silages OB and OBE. The non-fiber carbohydrates (NFC) decreased (16.67 to 14.05% DM) and the crude protein (CP) did not change (mean of 8.98% DM) during the aerobic exposure in all silages. The buffering capacity (BC) decreased, while pH and the ammonia nitrogen (NH3-N) increased during the aerobic exposure in all silages. Independent from the aerobic exposure period, BC of OBE silage was higher than O silage (29.67 vs. 24.80 meq/100 g DM). Lactic acid bacteria count in OB silage (7.83 log CFU/g) was higher than in O and OBE silages (5.24 log CFU/g, on average). Also, the OB silage showed high enterobacteria count compared to OBE silage (2.49 vs. 0.76 log CFU/g). The inoculation with Lactobacillus plantarum, Pediococcus acidilactici and amylase enzyme at the dose of 1×105 CFU/g does not improve the aerobic stability, nutritional value and the fermentation and microbiological profiles of oat silages.

研究概述 本研究评估了接种剂添加对白燕麦青贮饲料（*Avena sativa* L.）的有氧稳定性、营养价值以及发酵与微生物学特征的影响。试验采用完全随机设计，设置3个处理组与6个生物学重复。3种青贮处理方式分别为：仅燕麦青贮（O组）、燕麦添加同型发酵细菌接种剂（OB组）、燕麦添加细菌-酶复合接种剂（OBE组）。结果显示，O组青贮饲料的有氧稳定性为9天，OB组与OBE组青贮饲料的有氧稳定性均为14天。所有青贮饲料在有氧暴露期间，非纤维碳水化合物（non-fiber carbohydrates, NFC）占干物质（dry matter, DM）的比例从16.67%降至14.05%，而粗蛋白质（crude protein, CP）占干物质的比例无显著变化（均值为8.98% DM）。所有青贮饲料的缓冲容量（buffering capacity, BC）均出现下降，pH值与氨态氮（ammonia nitrogen, NH₃-N）含量则呈上升趋势。无论有氧暴露时长如何，OBE组青贮饲料的缓冲容量均显著高于O组（29.67 vs 24.80 meq/100 g DM）。OB组青贮饲料的乳酸菌菌落数（7.83 log CFU/g）显著高于O组与OBE组（平均5.24 log CFU/g）；同时，OB组青贮饲料的肠杆菌科细菌计数也显著高于OBE组（2.49 vs 0.76 log CFU/g）。以1×10⁵ CFU/g的剂量添加植物乳杆菌、乳酸片球菌与淀粉酶接种剂，无法改善燕麦青贮饲料的有氧稳定性、营养价值以及发酵与微生物学特征。