Submitted to: Encyclopedia of Animal Science
Publication Type: Book / Chapter
Publication Acceptance Date: March 10, 2010
Publication Date: November 18, 2010
Citation: Callaway, T.R., Martin, S.A., Edrington, T.S., Delay, S.W., Anderson, R.C., Nisbet, D.J. 2010. Rumen microbiology. In: Pond, W.G., Ullrey, D., Kirk-Baer, C., editors. Encyclopedia of Animal Science, 2nd edition. New York, NY: Taylor-Francis Group. p. 950-953. Technical Abstract: Ruminant animals such as cattle, sheep, and goats are able to digest low-quality fibrous feedstuffs because they maintain a mutually beneficial relationship with microorganisms resident in their forestomach, the rumen. Ruminal microorganisms are bacteria, protozoa, fungi, and viruses that live in an anaerobic consortium that degrades and ferments feedstuffs. Fermentation end-products, such as volatile fatty acids and microbial crude protein, in turn, provide the animal with usable nutrients. The rumen is one of the richest and most diverse microbial habitats known, with bacterial populations known to be >10 cells/ml or ruminal fluid. Ruminal fermentation of feedstuffs is critical to the survival and success of ruminant animals, but is an inherently inefficient process. Therefore, improving the efficiency of the ruminal fermentation is important in improving environmental quality and producer profitability.