Bacterial and fungal core microbiomes associated with small grain silages during ensiling and aerobic spoilage.
Bacterial and fungal core microbiomes associated with small grain silages during ensiling and aerobic spoilage.
复制标题
DOI：
10.1186/s12866-017-0947-0
复制
发表时间：
2017-03-03
期刊：
影响因子：
4.2
通讯作者：
McAllister TA
中科院分区：
文献类型：
--
作者：
Duniere L;Xu S;Long J;Elekwachi C;Wang Y;Turkington K;Forster R;McAllister TA
描述小颗粒青贮饲料中存在的微生物种群并了解它们在青贮过程中的变化对于提高这些重要饲料作物的营养价值具有重要意义。收获大麦、燕麦和小黑麦牧草以及3种作物的间作混合物，并在小型筒仓中青贮90天，然后进行14天的有氧暴露。利用16 S和18 S rDNA序列分析技术，分别对终末青贮饲料发酵特性和营养价值的变化进行了研究。所有小粒青贮饲料均表现出与优质青贮饲料相关的化学特性，如低pH值（4.09 ± 0.28）和高乳酸含量（59.8 ± 14.59 mg/g DM）。随着青贮时间的延长，微生物核心基因组操作分类单位（OTUs）的数量逐渐减少。分类细菌群落分布占主导地位的乳酸杆菌发酵后，与一个显着增加的芽孢杆菌作为有氧暴露的结果。在青贮期间，真菌核心微生物组的多样性也显示出减少。在青贮和有氧暴露后的核心微生物组中发现了分配给丝状真菌的操作分类单位，而在青贮和有氧暴露90天后，真菌目是占主导地位的酵母菌群。在有氧暴露后，在核心微生物组中鉴定了通常与青贮饲料腐败相关的细菌和真菌。新一代测序技术成功地描述了整个青贮和利用过程中的细菌群落和真菌群落的第一个记录。准确描述青贮饲料的微生物生态学可以改善青贮实践，并选择与天然饲料微生物组协同作用的青贮饲料接种剂。本文的在线版本（doi：10.1186/s12866-017-0947-0）包含补充材料，可供授权用户使用。
Describing the microbial populations present in small grain silage and understanding their changes during ensiling is of interest for improving the nutrient value of these important forage crops. Barley, oat and triticale forages as well as an intercropped mixture of the 3 crops were harvested and ensiled in mini silos for a period of 90 days, followed by 14 days of aerobic exposure. Changes in fermentation characteristics and nutritive value were assessed in terminal silages and bacterial and fungal communities during ensiling and aerobic exposure were described using 16S and 18S rDNA sequencing, respectively. All small grain silages exhibited chemical traits that were associated with well ensiled forages, such as low pH value (4.09 ± 0.28) and high levels of lactic acid (59.8 ± 14.59 mg/g DM). The number of microbial core genome operational taxonomic units (OTUs) decreased with time of ensiling. Taxonomic bacterial community profiles were dominated by the Lactobacillales after fermentation, with a notable increase in Bacillales as a result of aerobic exposure. Diversity of the fungal core microbiome was shown to also be reduced during ensiling. Operational taxonomic units assigned to filamentous fungi were found in the core microbiome at ensiling and after aerobic exposure, whereas the Saccharomycetales were the dominate yeast population after 90 days of ensiling and aerobic exposure. Bacterial and fungal orders typically associated with silage spoilage were identified in the core microbiome after aerobic exposure. Next Generation Sequencing was successfully used to describe bacterial communities and the first record of fungal communities throughout the process of ensiling and utilization. Adequately describing the microbial ecology of silages could lead to improved ensiling practices and the selection of silage inoculants that act synergistically with the natural forage microbiome. The online version of this article (doi:10.1186/s12866-017-0947-0) contains supplementary material, which is available to authorized users.