Rumina, definition

VVThile relatively little information is available on species of bacteria functional in anaerobic ecosystems such as the digesters of sewage treatment facilities so that definitive nutritional studies can be carried out, most species of bacteria functional in the rumen have been described, and many nutritional features of many of these species have been determined (J, 2). These nutritional studies of axenic rumen species have yielded much qualitative information, important to the understanding of this ecosystem, that would be difficult or impossible to obtain and interpret via studies on the nutritional characteristics of the mixed population (3). 

The reason for the inefiiciency of these bacteria in utilizing amino acids is not definitely known however, it seems probable, as is the case with some of the carbohydrate-fermenting rumen bacteria (8, 33), that these materials are not transported effectively into the cell. It seems probable that, in their adaptation to the natural habitat, their abilities to utihze proteins and amino acids were of little survival value and were lost. It is well known that amino acids are present in very small amounts in extracellular fiuid of rumen contents while relatively high concentrations of ammonia and acetate and other volatile acids including 2-methylbutyrate are present (8). A similar condition probably exists in sludge although the volatile acids are usually present in lower concentration than in the rumen. 

There is a definite need to analyze all the trans- % isomers since some of the isomers are precursors to CLA. In addition, the complete trans isomer and CLA profiles in milk and meat fats of ruminants provides an excellent indicator of the rumen bacterial state, specifically the content of 1 Of-18 1. A complete trans isomer composition will provide an accurate database to compare the current isomer profile between ruminant fats and partially hydrogenated fats. 

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