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对白燕麦青贮料（栽培燕麦*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次重复。处理组对应3种青贮方式：燕麦青贮组（O）、添加同型发酵细菌接种剂的燕麦青贮组（OB）以及添加细菌-酶复合接种剂的燕麦青贮组（OBE）。
结果表明，O组青贮料的有氧稳定性为9天，OB与OBE组青贮料的有氧稳定性均为14天。所有青贮料在有氧暴露过程中，非纤维碳水化合物（non-fiber carbohydrates, NFC）占干物质百分比由16.67%降至14.05%，而粗蛋白（crude protein, CP）无显著变化（平均占干物质8.98%）。缓冲能力（buffering capacity, BC）呈下降趋势，pH值与氨态氮（ammonia nitrogen, NH₃-N）则在所有青贮料的有氧暴露阶段均有所升高。
无论有氧暴露时长如何，OBE组青贮料的缓冲能力均高于O组（29.67 vs. 24.80 meq/100 g DM）。OB组青贮料的乳酸菌菌落数（7.83 log CFU/g）显著高于O组与OBE组（平均5.24 log CFU/g）。此外，OB组青贮料的肠杆菌菌落数高于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（Lactobacillus plantarum）、乳酸片球菌（Pediococcus acidilactici）与淀粉酶的接种方案，未能提升燕麦青贮料的有氧稳定性、营养价值以及发酵与微生物学特征。