Bacteria of the Rumen Ecosystem and their Roles

The rumen ecosystem compromised of bacteria, archaea, protozoa, fungi, and bacteriophages. Bacteria are the predominant mass of microbiological beings and account for nearly 40-60% of total microbial beings in the rumen. Ruminants are fed mainly on lingocellulosic agricultural by-products which are rich in cellulose, hemicellulose, lignin, starch, protein and a very small quantity of oils. The rumen hosts various types of bacteria which are degrading of these compo-nents of the feed. In the rumen environment more than 200 species of bacteria has been isolated and at least 20 species have been measured at 10^7-10^10 in number. Those of the bacteria which are measured more than 10^7 are considered as dominant species. Due to the interactions among these respective microbiological groups and bacteria, volatile fatty acids (VFA), carbondioxide, methane, ammonia and other microbiological products are producted. Microbiological proteins and vitamines are seriously essential for ruminants which are synthesised in the rumen. The interractions between various microbiological groups is essential for maintaining fermentation and stability of microbiological sentients. Quantity and ratio of microorganisms in the rumen are posing differences according to the composition of ration, species of animal, ratio of the volatile fatty acids, formation of the feed, pH of the rumen. In this review, the identifications, characterisations and determination of the roles that are partaking of these bacteria in the rumen have been overviewed.