The rumen microbiome: Abrief review

The rumen microbiome is a complex dynamic community of microorganisms that participate in digestion and provide an utmost impact on the cattle efficiency. Despite significant advancements in microbiome research, understanding the formation and management of the rumen microbiome still remains a significant scientific challenge. This topic holds both economic and environmental importance. The purpose of this literature review is to analyze and arrange structurally the current knowledge about the composition and functions of the rumen microbiome for further application of this knowledge in livestock farming. The article emphasizes that diet is an important factor that defines the composition and variability of the microbiome. This work demonstrates that the main functions of the rumen are provided by mutually coordinated groups of bacteria, methanogenic archaea, bacteriophages, protozoa, and fungi. The review covers various microbial groups in the rumen and their functions, as well as the factors that influence changes in the microbial community. Traditional methods of studying the rumen microbiome, based on culture-based techniques, have been significantly improved by the introduction of modern sequencing technologies. The review also explores the history of microbiome research and the “Hungate 1000 collection” project. This work demonstrates how metagenomics, metatranscriptomics, and metaproteomics have not only discovered numerous previously unknown microorganisms, but also provided insights into their functional roles. The systematization of knowledge presented in this review provides a comprehensive understanding of the rumen microbiome as a dynamic object for innovation targeted at improving the productivity, sustainability, and environmental safety of modern livestock farming.

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