Methanogenesis in the Rumen: Mass Spectrometric Monitoring
The rumen is the most economically-important of all natural fermentation systems. The productivity of cattle, sheep and goats, and of ruminant wild animals, depends on the efficiency of its microbial interconversions, especially the production of low molecular weight compounds from plants such as cellulose and hemicellulose polymers (Hungate, 1966; Hobson, 1976). In the sheep, the volume of the rumen is 6–101, and in the cow is about 100. A highly complex population of symbiotic microorganisms carries out these processes, and although the overall balances of inputs and outputs have been intensively studied, many datails await elucidation. Rumen fluid is rich in volatile fatty acids and vitamins, but for much of the day is starved of starch, glucose and other readily metabolised nutrients. Even some fundamental aspects of the fermentations are only becoming appreciated very recently. For example, approximately one half of the biomass of organisms within the rumen is accounted for by the protozoa (Williams, 1986). Selective removal of these organisms (“defaunation”) leads to their replacement by bacteria, and the host mammal apparently suffers little nutritional imbalance as a consequence.What then is the exact function of the rumen protoza?
KeywordsAnaerobic Digester Rumen Fluid Rumen Fermentation Methanosarcina Barkeri Membrane Inlet Mass Spectrometry
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