Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-25T01:26:30.819Z Has data issue: false hasContentIssue false

Excretion of purine derivatives by ruminants: recycling of allantoin into the rumen via saliva and its fate in the gut

Published online by Cambridge University Press:  09 March 2007

X. B. Chen
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
F. D. DeB. Hovell
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
E. R. ØRskov
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The saliva of sheep was shown to contain significant concentrations of uric acid (16 (sd) 4.5) μmol/l) and allantoin (120 (sd 16.4) μmol/l), sufficient to recycle purine derivatives equivalent to about 0.10 of the normal urinary excretion. When allantoin was incubated in vitro in rumen fluid, it was degraded at a rate sufficient to ensure complete destruction of recycled allantoin. In a series of experiments in which allantoin was infused into the rumen of sheep fed normally, or into the rumen or abomasum of sheep and the rumen of cattle completely nourished by intragastric infusion of volatile fatty acids and casein, no additional allantoin was recovered in the urine. These losses were probably due to the degradation of allantoin by micro-organisms associated with the digestive tract. It is concluded that all allantoin and uric acid recycled to the rumen via saliva will be similarly degraded. Therefore, the use of urinary excretion of purine derivatives as an estimator of the rumen microbial biomass available to ruminants will need to be corrected for such losses.

Type
Rumen Digestion and Metabolism
Copyright
Copyright © The Nutrition Society 1990

References

Abou Akkada, A. R. & Howard, B. H. (1960). The biochemistry of rumen protozoa. 3. The carbohydrate metabolism of Entodinium. Biochemical Journal 76, 445451.CrossRefGoogle Scholar
Berlin, R. D. & Hawkins, R. A. (1968). Secretion of purines by the small intestine: general characteristics. American Journal of Physiology 215, 932941.CrossRefGoogle ScholarPubMed
Belasco, I. J. (1954). New nitrogen feed compounds for ruminants - a laboratory evaluation. Journal of Animal Science 13, 601610.CrossRefGoogle Scholar
Chen, X. B. (1989). Excretion of purine derivatives by sheep and cattle and its use for the estimation of absorbed microbial protein, PhD Thesis, University of Aberdeen.Google Scholar
Chen, X. B., Hovell, F. D. DeB., Ørskov, E. R. & Brown, D. S. (1990a). Excretion of purine derivatives by ruminants: effect of exogenous nucleic acid supply on purine derivative excretion by sheep. British Journal of Nutrition 63, 131142.CrossRefGoogle ScholarPubMed
Chen, X. B., Kyle, D. J., Whyte, C. C., Hovell, F. D. DeB. & Ørskov, E. R. (1989). Uric acid and allantoin in plasma and saliva of sheep. Proceedings of the Nutrition Society 48, 88A.Google Scholar
Chen, X. B., Mathieson, J., Hovell, F. D. DeB. & Reeds, P. J. (1990b). Measurement of purine derivatives in urine of ruminants using automated methods. Journal of the Science of Food and Agriculture (In the Press).CrossRefGoogle Scholar
Czerkawski, J. W. & Breckenridge, G. (1977). Design and development of a long-term rumen simulation technique (Rusitec). British Journal of Nutrition 38, 371384.CrossRefGoogle ScholarPubMed
Hovell, F. D. DeB., Ørskov, E R., Kyle, D. J. & MacLeod, N. A. (1987). Undernutrition in sheep: nitrogen repletion by N-depleted sheep. British Journal of Nutrition 57, 7788.CrossRefGoogle ScholarPubMed
Katz, F. H. & Sorensen, L. B. (1968). Parotid fluid uric acid. Clinical Research 16, 387 Abstr.Google Scholar
Kay, R. N. B. (1966). The influence of saliva on digestion in ruminants. World Reviews of Nutrition and Dietetics 6, 292325.CrossRefGoogle ScholarPubMed
Lawes Agricultural Trust (1984). Genstat 4 User Manual. Rothamsted: Rothamsted Experimental Station.Google Scholar
McAllan, A. B. (1980). The degradation of nucleic acid in, and the removal of breakdown products from the small intestines of steers. British Journal of Nutrition 44, 99112.CrossRefGoogle ScholarPubMed
McAllan, A. B. & Smith, R. H. (1973). Degradation of nucleic acid derivatives by rumen bacteria in vitro. British Journal of Nutrition 29, 467474.CrossRefGoogle ScholarPubMed
MacLeod, N. A., Corrigall, W., Stirton, R. A. & Ørskov, E. R. (1982). Intragastric infusion of nutrients in cattle. British Journal of Nutrition 47, 547552.CrossRefGoogle ScholarPubMed
Malawar, S. J. & Powell, D. P. (1967). Improved turbidimetric analysis of polyethylene glycol using an emulsifier. Gastroenterology 53, 250256.CrossRefGoogle Scholar
Ørskov, E. R., Grubb, D. A., Wenham, G. & Corrigall, W. (1979). The sustenance of growing and fattening ruminants by intragastric infusion of volatile fatty acid and protein. British Journal of Nutrition 41, 553558.CrossRefGoogle ScholarPubMed
Ross, G. J. S. (1987). MLP User Manual. Rothamsted: Rothamsted Experimental Station.Google Scholar
Sorensen, L. B. (1960). The elimination of uric acid in man. Scandinavian Journal of Clinical and Laboratory Investigation 12, Suppl. 54, 1214.Google Scholar
Topps, J. H. & Elliott, R. C. (1965). Relationships between concentrations of ruminal nucleic acid and excretion of purine derivatives by sheep. Nature 205, 498499.CrossRefGoogle Scholar
Verbic, J., Chen, X. B., MacLeod, N. A. & Ørskov, E. R. (1990). Excretion of purine derivatives by ruminants: Effects of microbial nucleic acid infusion on purine derivative excretion in steers Journal of Agricultural Science, Cambridge (In the Press).CrossRefGoogle Scholar
Wallace, R. J., Cheng, K. J., Dinsdale, D. & Ørskov, E. R. (1979). An independent microbial flora of the epithelium and its role in the ecomicrobiology of the rumen. Nature 279, 424426.CrossRefGoogle ScholarPubMed