对于打包的青贮饲料,超过正常水分目标(45%至55%)会加剧梭菌发酵产品的生产,和/或通过在收获前施用乳品浆料。我们的目标是测试一种微生物接种剂作为高水分梭菌产品的缓解剂,草豆科植物(52%±13.8%冷季草,44.0%±14.0%豆科植物[主要是苜蓿])将青贮饲料打包,然后用乳汁施肥。第二个目的是检查捆包水分和接种对暴露于空气后这些发酵青贮饲料的有氧稳定性的影响。移除第一次切割后,将三种粪肥处理作为一个整体因素进行:1)对照(无粪肥);2)立即施用于残茬的浆液(63,250L/ha);或3)延迟1周(57,484L/ha)后施用的浆液。在实验中,捆包水分(64.1%或48.4%)和接种(是或否)的相互作用排列作为子图项。接种剂包含同乳酸(乳酸乳球菌0224)和异乳酸(布氏乳杆菌LB1819)细菌。实验设计被分析为一个随机完整的块,有四个重复,研究包括48个实验单元(1.2×1.2-m圆包)。总发酵酸受到浆液施用策略的影响(P≤0.021),但这可能与泥浆施用处理中的捆湿度不一致有关。丁酸的浓度很低,与粪肥处理相比,没有可检测到的对比(平均值=0.05%;P≥0.645)。捆包水分影响发酵的所有措施,在64.1%水分下制成的捆包表现出更酸性的最终pH(4.39vs.4.63;P<0.001),较少残留的水溶性碳水化合物(2.1%vs.5.1%;P<0.001),以及更多的乳酸(4.64%vs.2.46%;P<0.001),乙酸(2.26%vs.1.32%;P<0.001),和总发酵酸(7.37%vs.3.97%;P<0.001)。接种也降低了pH(4.47vs.4.56;P=0.029),和增加乙酸(1.97%vs.1.61%;P<0.001)和1,2-丙二醇(1.09%vs.0.72%;P<0.001)与对照组相比。在34天的有氧暴露期间,处理的任何方面都不影响最大表面捆包温度(P≥0.186),可能是由于普遍的凉爽环境温度;然而,响应于高捆包水分和接种刺激的更高(P<0.001)的乙酸产量,酵母计数在数字上较低。
这项研究的目的是测试一种接种剂,以减轻高水分青贮包的梭菌产品的生产,在前一个生长周期中,用乳汁处理牧草。尽管应用了乳浆,以及高于建议的捆包湿度,发酵后观察到典型梭菌产物的浓度仅为最低。接种对氨-N或丁酸的最终浓度没有影响。梭菌反应的缺乏可能是由这些牧草生长过程中的许多强降雨事件来解释的。打包后及时包装,底物充足性,以及非常低的缓冲能力,特别是与大多数混合相比,以前在这个地方收获的豆科植物草。因此,使用异型和同型乳酸组合接种剂来减轻梭菌活性尚无定论。包水分和接种对发酵后乙酸浓度均有积极影响,并导致在暴露于空气34d后,酵母菌的数量在数值上减少:然而,表面捆包温度保持凉爽,不管治疗,在很大程度上是对11月威斯康星州中部发生的凉爽环境温度的反应。
For baled silages, production of clostridial fermentation products can be exacerbated by exceeding normal moisture targets (45% to 55%), and/or by the application of dairy slurry before harvest. Our objectives were to test a microbial inoculant as a mitigant of clostridial products in high-moisture, grass-legume (52% ± 13.8% cool-season grasses, 44.0% ± 14.0% legumes [predominately alfalfa]) baled silages in swards that were fertilized with dairy slurry. A secondary objective was to examine the effects of bale moisture and inoculation on the aerobic stability of these fermented silages following exposure to air. After the first-cutting was removed, three manure treatments were applied as a whole-plot factor: 1) control (no manure); 2) slurry applied immediately to stubble (63,250 L/ha); or 3) slurry applied after a 1-wk delay (57,484 L/ha). An interactive arrangement of bale moisture (64.1% or 48.4%) and inoculation (yes or no) served as a subplot term in the experiment. The inoculant contained both homolactic (Lactococcus lactis 0224) and heterolactic (Lactobacillus buchneri LB1819) bacteria. The experimental design was analyzed as a randomized complete block with four replications, and the study included 48 experimental units (1.2 × 1.2-m round bales). Total fermentation acids were affected (P ≤ 0.021) by slurry application strategies, but this was likely related to inconsistent bale moisture across slurry-application treatments. Concentrations of butyric acid were low, and there were no detectable contrasts comparing manure treatments (mean = 0.05%; P ≥ 0.645). Bale moisture affected all measures of fermentation, with bales made at 64.1% moisture exhibiting a more acidic final pH (4.39 vs. 4.63; P < 0.001), less residual water-soluble carbohydrates (2.1% vs. 5.1%; P < 0.001), as well as greater lactic acid (4.64% vs. 2.46%; P < 0.001), acetic acid (2.26% vs. 1.32%; P < 0.001), and total fermentation acids (7.37% vs. 3.97%; P < 0.001). Inoculation also reduced pH (4.47 vs. 4.56; P = 0.029), and increased acetic acid (1.97% vs. 1.61%; P < 0.001) and 1,2-propanediol (1.09% vs. 0.72%; P < 0.001) compared to controls. During a 34-d aerobic exposure period, maximum surface bale temperatures were not affected (P ≥ 0.186) by any aspect of treatment, likely due to the prevailing cool ambient temperatures; however, yeast counts were numerically lower in response to greater (P < 0.001) production of acetic acid that was stimulated by both high bale moisture and inoculation.
The objectives of this research were to test an inoculant to mitigate production of clostridial products in high-moisture silage bales, where forages were treated with dairy slurry during the preceding growth cycle. Despite the application of dairy slurry, as well as greater-than-recommended bale moisture, only minimal concentrations of typical clostridial products were observed following fermentation. Inoculation had no effect on final concentrations of either ammonia-N or butyric acid. The lack of clostridial response might be explained by numerous strong rainfall events during the growth of these forages, prompt wrapping following baling, substrate adequacy, as well as an exceptionally low buffering capacity, particularly compared to most mixed, legume-grass swards harvested previously at this location. As a result, using a combination hetero- and homolactic inoculant to mitigate clostridial activity was inconclusive. Both bale moisture and inoculation had positive effects on concentrations of acetic acid following fermentation, and resulted in numerically reduced counts of yeasts following a 34-d exposure to air: however, surface bale temperatures remained cool, regardless of treatment, largely in response to the cool ambient temperatures that occurred in central Wisconsin during November.