Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-18T10:34:33.215Z Has data issue: false hasContentIssue false

The clearance rate of rumen liquid and rumen fermentation pattern in sheep receiving forage diets

Published online by Cambridge University Press:  27 March 2009

P. C. Thomas
Affiliation:
The Hannah Research Institute, Ayr KA6 5HL
J. C. Hodgson
Affiliation:
The Hannah Research Institute, Ayr KA6 5HL

Summary

An experiment was carried out to study the composition of the mixture of rumen short-chain fatty acids and the clearance rate of the rumen liquid phase in sheep given diets of dried grass, high-nitrogen hay, low-nitrogen hay and barley straw. Differences between diets in clearance rate were not significant (P > 0·05) and differences between diets in the composition of the mixture of rumen acids were small. There were substantial variations in clearance rate between individual sheep but this was not associated with variations in the pattern of fermentation and the correlation between the proportion of propionic acid and the clearance rate in the rumen was low (r = –0·23).

In a second experiment sheep receiving a moderate-quality hay were given intravenous injections of atropine sulphate which resulted in significant increases in rumen volume (P < 0·01) and significant reductions in ruminal clearance rate (P < 0·05). These were accompanied by significant increases in the numbers of protozoa (P < 0·05) and bacteria (P < 0·05) in the rumen but the composition of the mixture of rumen short-chain fatty acids was unchanged.

It is concluded that there is little possibility through alteration of ruminal clearance rate, for manipulation of rumen fermentation pattern in sheep receiving diets of moderate- or poor-quality forages.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1979

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Blaxter, K. L. (1967). The Energy Metabolism of Ruminants, 2nd ed.London: Hutchinson.Google Scholar
Harrison, D. G., Beever, D. E., Thomson, D. J. & Osbounrne, D. F. (1975). Manipulation of rumen fermentation in sheep by increasing the rate of flow of water from the rumen. Journal of Agricultural Science, Cambridge 85, 93101.CrossRefGoogle Scholar
Harrison, D. G., Beever, D. E., Thomson, D. J. & Osbourn, D. F. (1976). Manipulation of rumen fermentation. Journal of the Science of Food and Agriculture 27, 617620.CrossRefGoogle Scholar
Hodgson, J. C. (1977). Physiological control of fermentation in the rumen. Ph.D. thesis, University of Leeds.Google Scholar
Hodgson, J. C. & Thomas, P. C. (1975). A relationship between the molar proportion of propionio acid and the clearance rate of the liquid phase in the rumen of sheep. British Journal of Nutrition 33, 447456.CrossRefGoogle Scholar
Hodgson, J. C., Thomas, P. C. & Wilson, A. G. (1976). The influence of the level of feeding on fermentation in the rumen of sheep receiving a diet of ground barley, ground hay and flaked maize. Journal of Agricultural Science, Cambridge 87, 297302.CrossRefGoogle Scholar
Ministry of Agriculture, Fisheries and Food (1975). Technical Bulletin 33. Energy Allowances and Feeding Systems for Ruminants. London: Her Majesty's Stationery Office.Google Scholar
Morrison, I. M. (1973). A note on the evaluation of the nutritive value of forage crops by the acetyl bromide technique. Journal of the British Grassland Society 28, 153154.CrossRefGoogle Scholar
Sinha, K. P., Sud, S. C. & Bagha, H. S. (1974). Studies on salivary secretion: The effect of autonomic drugs. Indian Veterinary Journal 51, 1519.Google Scholar
Snedecor, G. W. (1956). Statistical Methods. Iowa: Iowa State University Press.Google Scholar
Thomson, D. J., Beever, D. E., Latham, M. J., Sharpe, M. E. & Terry, R. A. (1978). The effect of inclusion of mineral salts in the diet on dilution rate, the pattern of rumen fermentation and the composition of the rumen microflora. Journal of Agricultural Science, Cambridge 91, 17.CrossRefGoogle Scholar
Waite, R. & Boyd, J. (1953). The water-soluble carbohydrates of grasses. Journal of the Sciences of Food and Agriculture 4, 257261.CrossRefGoogle Scholar
Warner, A. C. I. (1966). Diurnal changes in the concentrations of microorganisms in the rumen of sheep fed limited diets once daily. Journal of General Microbiology 45, 213235.CrossRefGoogle ScholarPubMed
Weston, R. H. & Hogan, J. P. (1967). The digestion of chopped and ground roughage by sheep. 1. The movement of digests through the stomach. Australian Journal of Agricultural Research 18, 789801.CrossRefGoogle Scholar