Sheep rumen, carbohydrates

RunUnococcus albus and Ruminococcus flavefadens. These bacteria are important cellulose-degraders found in the rumen of cattle and sheep (2). Most isolated strains ferment cellulose and xylan and all ferment cellobiose. Fermentation of glucose and some other carbohydrates depends on the particular strain. R flavefadens and B. succinogenes can ferment the highly ordered crystalline cellulosic su trates but R albus cannot. No evidence has been found for extracellular cellulase production by R albus, but Ohmiya et al. purified cellobiosidase from this culture 17). Laboratory growth of R albus has been conducted at pH 7.0 and 37 C. 

For many years, Hirst was a member of the Board of Governors of the Rowett Research Institute, Aberdeen, where he took a keen interest in the work of the Institute as a whole, and particularly that of Dr. A. E. Oxford and the microbiology department. This led to collaboration on the nature of the reserve carbohydrate synthesized by Cycloposthium and by the holotrich ciliates present in sheep s rumen. Both protozoal polysaccharides were shown to be amylopectin in type. The work was continued with other protozoa, in collaboration with J. F. Ryley, and the presence of starch or amylopectin-type polysaccharides was established in Chilomonas paratnecium, Haematococcus pluvialis, and Tet-raselmis carteriiformis. 

Phillipson, A.T. McAnally, R.A. (1942) Studies on the fate of carbohydrates in the rumen of the sheep. Journal of Experimental Biology, 19,199-214. 

Interaction of several diverse species of bacteria, fungi and protozoa facilitates the breakdown of cellulose and other carbohydrate fractions in plant materials in the rumen. With the decrease of protozoal numbers, this interaction may be disturbed as some carbohydrate degrading enzymes have less activity. Wina et al. (2005b, 2006a) showed that the xylanase activity in the rumen decreased when S. rarak saponin extract was administered to in vitro fermentation or directly to sheep. The CMCase activity was not affected in the in vitro, however, it was depressed by... 

These are carbohydrates which do not provide nourishment to humans. Man and other monogastric animals lack the enzymes necessary to breakdown such carbohydrates as cellulose, hemicellulose, and pectin. Often these carbohydrates are referred to as dietary fiber or roughage. Because of the microbial action in the rumen, ruminant animals—cattle, sheep, and goats can utilize carbohydrates that are unavailable to man and other monogastrics. 

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