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Dynamics of protozoa in the rumen of cattle

Published online by Cambridge University Press:  09 March 2007

D. Ffoulkes
Affiliation:
Department of Biochemistry, Microbiology and Nutrition, University of New England, Armidale, NSW 3051, Australia
R. A. Leng
Affiliation:
Department of Biochemistry, Microbiology and Nutrition, University of New England, Armidale, NSW 3051, Australia
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Abstract

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1. The dynamics of protozoa were studied in two groups of rumen-fistulated cattle fed on a basal diet of molasses ad lib., with oaten chaff given at 6 or 18 g/kg live weight. This diet resulted in different mixtures of protozoal species in the populations in the rumen.

2. The rumen protozoa were studied by intrarumen injections of protozoa labelled in vitro with [14CH3]choline. An indication of protozoal death and fermentation of protozoal cell residues was obtained by measuring 14C loss via the methane pool.

3. After a single injection of labelled protozoa, the decline in the specific radioactivity (μCi/g nitrogen) of the protozoal pool in the rumen indicated that first-order kinetic processes applied. Conversely the specific radioactivity of protozoa, incubated in rumen fluid, remained constant indicating no growth in vitro, presumably owing to a rapid exhaustion of essential nutrients.

4. The protozoal populations in the rumen of cattle fed on the diet with the low level of oaten chaff were mainly small ciliates; but on the higher level of chaff in the diet, the large ciliates were a higher proportion of the total protozoal population present.

5. The mean pool size of protozoa in the rumen was significantly larger and the protozoal half-life tended to be longer for cattle fed on the higher level of chaff in the diet. The apparent production rate of protozoa in cattle fed on each diet was not significantly different and there were no differences in the production rate of methane. The percentage losses of label from protozoa in the rumen via the methane pool were not significantly different on the two diets and indicated that 74% of the protozoa that were apparently irreversibly lost from the rumen could be accounted for by death and lysis in the rumen and therefore only 26% of protozoa apparently entered the lower digestive tract.

Type
Research Article
Copyright
Copyright © The Nutrition Society 1988

References

Beveridge, R. A. & Leng, R. A. (1981). Tropical Animal Production 6, 510.Google Scholar
Bird, S. H., Hill, M. K. & Leng, R. A. (1979). British Journal of Nutrition 42, 8187.CrossRefGoogle Scholar
Bird, S. H. & Leng, R. A. (1978 a). British Journal of Nutrition 40, 163167.CrossRefGoogle Scholar
Bird, S. H. & Leng, R. A. (1978 b). In Recent Advances in Animal Nutrition in Australia, pp. 110118 [Farrell, D. J. and Pran, Vohra, editors]. Armidale: University of New England Publishing Unit.Google Scholar
Bird, S. H. & Leng, R. A. (1985). In Biotechnology and Recombinant DNA Technology in the Animal Production Industries – Reviews in Rural Science 6, pp. 109117 [Leng, R. A., Barker, J. S. F., Adams, D. B. and Hutchinson, K. J., editors]. Armidale: University of New England Publishing Unit.Google Scholar
Broad, T. E. & Dawson, R. M. C. (1976). Journal of General Microbiology 92, 391397.CrossRefGoogle Scholar
Clarke, R. T. J. (1965). New Zealand Journal of Agricultural Research 8, 16.CrossRefGoogle Scholar
Clarke, R. T. J., Ulyatt, M. J. & Andrew, J. (1982). Applied and Environmental Microbiology 43, 12011204.CrossRefGoogle Scholar
Coleman, G. S., Dawson, R. M. C. & Grime, D. W. (1980). Proceedings of the Nutrition Society 39, 6A.Google Scholar
Demeyer, D. I. & Van Nevel, C. J. (1979). Annales de Recherches Vétérinaires 10, 277279.Google Scholar
Downes, A. M. & McDonald, I. W. (1964). British Journal of Nutrition 18, 153162.CrossRefGoogle Scholar
Leng, R. A. (1982). British Journal of Nutrition 48, 399415.CrossRefGoogle Scholar
Leng, R. A., Dellow, D. & Waghorn, G. (1986). British Journal of Nutrition 56, 453462.CrossRefGoogle Scholar
Leng, R. A., Gill, M., Kempton, T. J., Rowe, J. B., Nolan, J. V., Stachiw, S. J. & Preston, T. R. (1981). British Journal of Nutrition 46, 371384.CrossRefGoogle Scholar
Leng, R. A., Nolan, J. V., Cumming, G., Edwards, S. R. & Graham, C. A. (1984). Journal of Agricultural Science, Cambridge 102, 609613.CrossRefGoogle Scholar
Martin, J. L., Preston, T. R. & Elias, A. (1968). Cuban Journal of Agricultural Science 2, 6570.Google Scholar
Murray, R. M., Bryant, A. M. & Leng, R. A. (1976). British Journal of Nutrition 36, 114.CrossRefGoogle Scholar
Preston, T. R. & Leng, R. A. (1987). Matching Ruminant Production Systems with Available Resources in the Tropics and Sub-Tropics. Armidale, NSW: Penambul Books.Google Scholar
Rowe, J. B., Bobadilla, M., Fernandez, A., Encarnacion, J. C. & Preston, T. R. (1979). Tropical Animal Production 4, 7889.Google Scholar
Schwartz, H. M. & Gilchrist, F. M. C. (1975). In Digestion and Metabolism in the Ruminant, pp. 165179. [McDonald, I. W. and Warner, A. C. I., editors]. Armidale: University of New England Publishing Unit.Google Scholar
Ushida, K., Jouany, J. P. & Thivend, P. (1986). British Journal of Nutrition 56, 407419.CrossRefGoogle Scholar
Valdez, R. E., Alvarez, F. J., Ferreiro, H. M., Guerra, F., Lopez, J., Rasego, A., Blackburn, T. H., Leng, R. A. & Preston, T. R. (1977). Tropical Animal Production 2, 260272.Google Scholar
Veira, D. M. (1986). Journal of Animal Science 63, 15471560.CrossRefGoogle Scholar
Veira, D. M., Ivan, M. & Jui, P. Y. (1984). Canadian Journal of Animal Science 64, Suppl.22.CrossRefGoogle Scholar