瘤胃微生物生态群落是一个非常复杂的生物体系，有着巨大的基因资源以及丰富的生态资源。宏基因组学通过免培养技术，研究生境中全部微小生物遗传物质的总和，在研究瘤胃微生物代谢和开发瘤胃微生物资源上展示出强劲的优势。该技术的应用有望解决反刍动物营养研究中诸多热点或难点问题。为此，本文介绍了宏基因组文库构建和筛选流程，详细讨论了流程中目的基因/基因组富集方法、载体选择原则和样品核酸提取等方法，并对瘤胃宏基因组学的应用现状进行了综述。

Rumen microbiota is a complex biological system, with huge amount of genetic and ecological resource. Metagenomics as “the application of modern genomics techniques to the study of communities of microbial organisms directly in their natural environments, bypassing the need for isolation and lab cultivation of individual species” shows strong vitality in research of the metabolic pathway and exploring the gene resource of rumen microbiota. The application of metagenomics may solve many hot and difficult problems in rumen nutrition. Therefore, the construction and selection procedure were introduced in this paper. The methods of target gene/genome enrichment, the selection principle of vectors, the procedure of nucleic acid extraction, and the application of metagenomics in rumen were related in detail. ［Chinese Journal of Animal Nutrition, 2010，22（3）:527-535］