Department of Animal Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
J Dairy Sci. 2012 Jun;95(6):3354-62. doi: 10.3168/jds.2011-5207.
This project aimed to determine effects of applying an inoculant containing homofermentative and heterofermentative bacteria on the fermentation, nutritive value, aerobic stability, and nutrient losses from corn silage produced in farm-scale silos. Corn forage was harvested at 34% dry matter (DM) and treated without (control) or with 5 × 10⁵ cfu/g of Lactobacillus buchneri and Pediococcus pentosaceus. The inoculant was sprayed on alternate 8-row-wide swaths of forage, and the untreated and inoculated forages were alternately packed into 3.6-m-wide bag silos. Forty-five tonnes of corn forage were packed into each of 4 replicate bags per treatment and ensiled for 166 d. Silage removed from the bags (500 kg/d) was separated into good and spoiled (visibly moldy or darker) silage portions, and weighed for 35 d. Weekly composites were analyzed for chemical composition, aerobic stability, and fungal counts. Aerobic stability was measured using data loggers that recorded sample and ambient temperature every 30 min for 7 d. Inoculation did not affect the chemical composition of the spoiled or good silage but decreased the quantity (5.7 vs. 12.9 kg/d) and percentage (3.4 vs. 7.8) of spoiled silage in the bags by over 50%. Losses of crude protein (0.28 vs. 0.92 kg/d), gross energy (6.0 × 10⁴ vs. 1.8 × 10⁵ kJ/d), and neutral detergent fiber (1.34 vs. 4.12 kg/d) in spoiled silage were less in inoculated versus control silages. Inoculated silages had lower pH (3.91 vs. 3.99), lactate concentration (7.63 vs. 7.86%), lactate:acetate ratio (1.58 vs. 2.53%), and a greater acetate (5.11 vs. 3.56%) concentration than the control silage. Inoculated silages tended to have fewer yeasts (2.59 vs. 4.62 log cfu/g) than control silages, but aerobic stability was not different across treatments (14.7 vs. 9.5 h). Applying the inoculant made the fermentation more heterolactic, inhibited the growth of yeasts, and substantially reduced the amount of spoilage and the associated energy and nutrient losses.
本项目旨在确定在农场规模青贮窖中应用含有同型发酵和异型发酵细菌的接种剂对青贮玉米发酵、营养价值、有氧稳定性和养分损失的影响。青贮玉米在干物质含量为 34%时收获，并用（对照）或 5×10⁵cfu/g 布氏乳杆菌和戊糖片球菌处理。接种剂喷洒在青贮饲料的 8 行宽的交替条带上，未处理和接种的青贮饲料交替装入 3.6 米宽的袋式青贮窖中。每个处理 4 个重复袋中装填 45 吨青贮玉米，青贮 166 天。从袋中取出的青贮料（500kg/d）分为好的和变质的（明显发霉或颜色较深）青贮料部分，并称重 35 天。每周对青贮料进行化学组成、有氧稳定性和真菌计数的综合分析。有氧稳定性使用数据记录器测量，该记录器每 30 分钟记录一次样品和环境温度，持续 7 天。接种不会影响变质或好的青贮料的化学组成，但会使袋中变质青贮料的数量（5.7 比 12.9kg/d）和比例（3.4 比 7.8%）减少 50%以上。接种青贮料的粗蛋白（0.28 比 0.92kg/d）、总能（6.0×10⁴比 1.8×10⁵kJ/d）和中性洗涤纤维（1.34 比 4.12kg/d）在变质青贮料中的损失低于对照青贮料。接种青贮料的 pH 值（3.91 比 3.99）、乳酸浓度（7.63 比 7.86%）、乳酸：乙酸比（1.58 比 2.53%）和乙酸浓度（5.11 比 3.56%）均低于对照青贮料。接种青贮料的酵母数量（2.59 比 4.62logcfu/g）低于对照青贮料，但各处理之间的有氧稳定性没有差异（14.7 比 9.5h）。应用接种剂使发酵更异乳酸发酵，抑制酵母生长，并显著减少变质的数量以及相关的能量和养分损失。
