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Effect of severe dehydration and rapid rehydration on the activity of the rumen microbial population of black Bedouin goats

Published online by Cambridge University Press:  27 March 2009

A. Brosh
Affiliation:
Department of Zoology
B. Sneh
Affiliation:
Institute for Nature Conservation Research, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel69978
A. Shkolnik
Affiliation:
Department of Zoology

Summary

Drinking regimes of Bedouin goats affect their feeding behaviour and the ruminal environmental conditions, as expressed by changes in osmotic pressure as well as in pH of the rumen content. The osmotic concentration of the rumen content of a goat drinking once daily was 330 m-osmole/kg just before drinking. After water deprivation for 4 days, the osmotic concentration reached 360 m-osmole/kg and, immediately after excessive drinking, decreased to 82 m-osmole/kg. After a short while, the osmotic concentration increased to 300 m-osmole/kg and after 13 h reached the peak of 440 mosmole/kg, mainly owing to the release of degradation products. The pH was also affected by food consumption. Just prior to drinking, the pH in the rumen of dehydrated goats was 6·9. It decreased to 6·0 after excessive drinking and feeding. Later, it ranged between 6·4 and 7·1.

Most of the micro-organisms in the rumen are attached to the fibres fraction. No difference could be observed in direct bacterial counts in the fluid fraction between dehydrated and goats drinking daily. However, the number of protozoa was reduced in dehydrated goats, especially after excessive drinking, as some species of protozoa seem to explode in a hypo-osmotic ambient.

The fermentation capacity of the fibres fraction was higher than that of the fluid fraction, indicating also the presence of more micro-organisms in the fibres. In addition, the osmotic changes occurring during the dehydration-rehydration cycles had no significant effect on fermentation capability of the rumen micro-organisms.

At a low osmotic concentration in an NaCl deficient ambient, there was some decrease in fermentation rate, but this could be nullified with the addition of NaCl, which is required for microbial activity. The decrease in fermentation rate is not due to its effect on the osmotic concentration. The micro-organisms in the fibres fraction were found to be less affected by NaCl deficiency in the ambient medium.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1983

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References

Association of Official Agricultural Chemists (1965). Methods of Analysis, 9th edn.Washington, D.C.: Association of Agricultural Chemists.Google Scholar
Bergen, W. G. & Yokoyama, M. I. (1977). Productive limits to rumen fermentation. Journal of Animal Science 46 (3), 573584.CrossRefGoogle Scholar
Choshniak, I. & Shkolnik, A. (1978). The rumen as a protective osmotic mechanism during rapid rehydration in the black Bedouin goat. In Osmotic and Volume Regulation, Alfred Benson Symposium XI, Munksgaard 1978, pp. 344359.Google Scholar
El-Din, M. Z. & El-Shazly, K. (1969). Evaluation of the method of measuring fermentation rates and net growth of rumen micro-organisms. Applied Microbiology 17, 801804.CrossRefGoogle Scholar
El-Shazly, K. & Hungate, R. E. (1965). Fermentation capacity as a measure of net growth of rumen microorganisms. Applied Microbiology 13, 6269.CrossRefGoogle ScholarPubMed
Hecker, J. F., Budtz-Olsen, O. E. & Ostwald, M. (1964). The rumen as water store in sheep. Australian Journal of Agricultural Research 15, 961968.CrossRefGoogle Scholar
Hungate, R. E. (1966). The Rumen and its Microbes. London and New York: Academic Press.Google Scholar
Shkolnik, A., Borut, A., Choshniak, I. & Maltz, E. (1974). Water economy and drinking regimen of the Bedouin goat. In Symposium Israel-France, Bel Degan, Israel, Volcani Center, Special Publication 39, 7990.Google Scholar
Squires, V. R. (1973). Distance to water as a factor in performance of livestock on arid and semi-arid rangelands. Proceedings of Water–Animal Relations Symposium (ed. Maryland, H. F.), Soil Scientists, USDAARS –Western Region, Snake River Conservation Research Center, Kimberley, Idaho.Google Scholar
Warner, A. C. I. (1962). Enumeration of rumen microorganisms. Journal of General Microbiology 28, 119128.CrossRefGoogle Scholar
Warner, A. C. I. & Stacy, B. D. (1965). Solids in the rumen of sheep. Quarterly Journal of Experimental Physiology 50, 119128.Google Scholar