College of Grassland Science and Technology, China Agricultural University, Beijing, China.
Frontier Technology Research Institute, China Agricultural University, Shenzhen, China.
mSystems. 2024 Nov 19;9(11):e0068224. doi: 10.1128/msystems.00682-24. Epub 2024 Oct 23.
Alfalfa ( L.) is one of the most extensively cultivated forage crops globally, and its nutritional quality critically influences the productivity of dairy cows. Silage fermentation is recognized as a crucial technique for the preservation of fresh forage, ensuring the retention of its vital nutrients. However, the detailed microbial components and their functions in silage fermentation are not fully understood. This study integrated large-scale microbial culturing with high-throughput sequencing to thoroughly examine the microbial community structure in alfalfa silage and explored the potential pathways of nutritional degradation via metagenomic analysis. The findings revealed an enriched microbial diversity in silage, indicated by the identification of amplicon sequence variants. Significantly, the large-scale culturing approach recovered a considerable number of unique microbes undetectable by high-throughput sequencing. Predominant genera, such as , , , , and , were identified based on their abundance and prevalence. Additionally, genes associated with Enterobacteriaceae were discovered, which might be involved in pathways leading to the production of ammonia-N and butyric acid. Overall, this study offers a comprehensive insight into the microbial ecology of silage fermentation and provides valuable information for leveraging microbial consortia to enhance fermentation quality.
Silage fermentation is a microbial-driven anaerobic process that efficiently converts various substrates into nutrients readily absorbable and metabolizable by ruminant animals. This study, integrating culturomics and metagenomics, has successfully identified core microorganisms involved in silage fermentation, including those at low abundance. This discovery is crucial for the targeted cultivation of specific microorganisms to optimize fermentation processes. Furthermore, our research has uncovered signature microorganisms that play pivotal roles in nutrient metabolism, significantly advancing our understanding of the intricate relationships between microbial communities and nutrient degradation during silage fermentation.
紫花苜蓿（L.）是全球广泛种植的饲料作物之一，其营养价值对奶牛的生产力至关重要。青贮发酵被认为是保存新鲜饲料的关键技术，可确保其重要营养物质的保留。然而，青贮发酵中微生物的详细组成及其功能尚未完全了解。本研究结合大规模微生物培养和高通量测序，全面研究了紫花苜蓿青贮中的微生物群落结构，并通过宏基因组分析探索了营养物质降解的潜在途径。研究结果表明，青贮中微生物多样性丰富，通过扩增子序列变异体鉴定得到证实。重要的是，大规模培养方法回收了大量高通量测序无法检测到的独特微生物。根据丰度和普遍性，确定了主要属，如 、 、 、 、和 。此外，还发现了与肠杆菌科相关的基因，这些基因可能参与导致氨氮和丁酸产生的途径。总体而言，本研究深入了解了青贮发酵的微生物生态学，并为利用微生物群落来提高发酵质量提供了有价值的信息。
青贮发酵是一种微生物驱动的厌氧过程，可有效地将各种底物转化为反刍动物可吸收和代谢的营养物质。本研究通过培养组学和宏基因组学的结合，成功鉴定了参与青贮发酵的核心微生物，包括那些丰度较低的微生物。这一发现对于有针对性地培养特定微生物以优化发酵过程至关重要。此外，我们的研究还揭示了在营养物质代谢中起关键作用的特征微生物，显著提高了我们对微生物群落与青贮发酵过程中营养物质降解之间复杂关系的理解。
