Until recently, knowledge of ruminant gut microbiology was primarily obtained using classical culture based techniques, which probably only account for 10 to 20% of the rumen microbial population. New gene-based technologies can now be employed to examine microbial diversity through the use of small sub-unit ribosomal DNA analysis (e.g. 16S rDNA) and to understand the function of complex microbial ecosystems in the rumen through metagenomic analysis. These technologies have the potential to revolutionize the understanding of rumen function and will overcome the limitations of classical based techniques, including isolation and taxonomic identification of strains important to efficient rumen function and better understanding of the roles of microorganisms in relation to achieving high productivity and decreasing environmental pollutants. This book presents a comprehensive up-to-date account of the methodologies and protocols for conventional and modern molecular techniques that are currently in use for studying the gut microbial ecology of ruminants. Each chapter has been contributed by experts in the field and methods have been presented in a recipe-like format designed for direct practical use in the laboratory and also to provide insight into the most appropriate techniques, their applications and the type of information that could be expected. The techniques and procedures described are also relevant and adaptable to other gastrointestinal ecosystems and the microbiology of anaerobic environments in general. This manual will ?demystify? the methods in molecular microbial ecology for readers who are novice in the field but are excited by the prospects of the technology. It would also be invaluable for the experienced workers striving for giving new dimension to their research ? expanding the work in other fields and initiating cross-cutting activities.