Hostname: page-component-848d4c4894-sjtt6 Total loading time: 0 Render date: 2024-06-28T00:01:33.186Z Has data issue: false hasContentIssue false
  • English
  • Français

The degradation of nucleic acids in, and the removal of breakdown products from the small intestines of steers

Published online by Cambridge University Press:  09 March 2007

A. B. McAllan
A. B. McAllan
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
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.

1. Nucleic acids and breakdown products were estimated in digesta taken from different sites in the small intestines of slaughtered steers given different diets. Amounts passing different sites were compared using cellulose as a non-digestible marker. The validity of this marker was checked with chromic oxide in some experiments. In other experiments, nucleic acids or derivatives were infused into the proximal duodenum of steers receiving diets of approximately equal proportions of flaked maize and hay. The amounts disappearing during passage through the small intestine were estimated using polyethylene glycol (PEG) as a non- absorbable marker.

2. In the slaughter experiments the amounts of nucleic acids entering the small intestine varied with the type of diet. RNA and DNA disappeared on average, to extents of 89% and 80% respectively between the abomasum and the terminal ileum, irrespective of the diet. RNA disappearance occurred almost entirely in the proximal quarter of the small intestine, whereas that of DNA extended further along the tract.

3. Nucleic acid degradation in the upper small intestine was accompanied by the transient appearance of adenosine, guanosine and pyrimidine nucleosides. These products were in greatest concentration in digesta from the first quarter of the small intestine and had generally completely disappeared by the terminal ileum.

4. Of the different substances infused into the small intestine, free nucleic acids were removed to extents greater than 97%, adenine, guanine and uracil had completely disappeared, thymine and xanthine to approximately 80% and 95% and hypoxanthine and cytosine to only 51% and 48% respectively. The nucleosides adenosine and cytidine were also completely removed in the small intestine but were replaced, in part, by the catabolic products inosine plus hypoxanthine or cytosine respectively. Other nucleosides were removed to approximately half the extent of the corresponding bases.

5. Serum and urine allantoin and uric acid levels were related to the amounts of purines entering the small intestines in free or bound form.

Type
Papers on General Nutrition
Information
British Journal of Nutrition , Volume 44 , Issue 1 , July 1980 , pp. 99 - 112
Copyright
Copyright © The Nutrition Society 1980

References

REFERENCES

Anderson, N. G. & Ladd, F. C. (1962). Biochim. biophys. Acta 55, 275.CrossRefGoogle Scholar
Armstrong, D. G. & Hutton, K. (1975). In Digestion and Metabolism in the Ruminant, pp. 432–447 [McDonald, I.W. and Warner, A. C. I., editors]. Armidale: University of New England Publishing Unit.Google Scholar
Badawy, A. M., Campbell, R. M., Cuthbertson, D. P., Fell, F. B. & Mackie, W. S. (1958). Br. J. Nutr. 12, 367.CrossRefGoogle Scholar
Barnard, E. A. (1969). Nafure, Lond. 221, 340.Google Scholar
Centar, M. S. & Behal, F. J. (1966). Archs Biochem. Biophys. 114, 414.CrossRefGoogle Scholar
Christman, A. A. (1952). Physiol. Rev. 32, 303.CrossRefGoogle Scholar
Coehlo da Silva, J. F., Seeley, R. C., Beever, D. E., Prescott, J. H. D. & Armstrong, D. J. (1972). Br. J. Nutr. 28, 357.CrossRefGoogle Scholar
Coehlo da Silva, J. F., Seeley, R. C., Thomson, D. J., Beever, D. E. & Armstrong, D. J, (1972). Br. J. Nutr. 28, 43.CrossRefGoogle Scholar
Condon, R. J. (1971). Diss. Abstr. int. 32B. 641.Google Scholar
Condon, R. J., Hall, G. & Hatfield, E. E. (1970). J. anim. Sci. 31, 1037.Google Scholar
Condon, R. J. & Hatfield, E. E. (1971). Fedn Proc. Fedn Am. Socs exp. Biol. 30, 402.Google Scholar
Ellis, W. C. & Bleichner, K. L. (1969). Fedn Proc. Fedn Am. Socs exp. Biol. 28, 623.Google Scholar
Gregory, M. E. (1954). Br. J. Nutr. 8, 340.Google Scholar
Jackson, T. C., Schelling, G. T., Mitchell, G. E. & Tucker, R. E. (1976). J. Anim. Sci. 43, 325.Google Scholar
Kaplan, V. A. & Pobirsky, N. N. (1974). Skh. Biol. 9, 91.Google Scholar
McAllan, A. B. & Smith, R. H. (1969). Br. J. Nutr. 23, 671.CrossRefGoogle Scholar
McAllan, A. B. & Smith, R. H. (1973). Br. J. Nufr. 29, 331.CrossRefGoogle Scholar
McAllan, A. B. & Smith, R. H. (1974). Br. J. Nutr. 31, 77.CrossRefGoogle Scholar
MacKinnon, A. M. & Deller, D. J. (1973). Biochim. biophys. Acta 319, 1.Google Scholar
McMeniman, N.P. (1975). Aspects of nitrogen digestion in the ruminant. PhD Thesis. University of Newcastle upon Tyne.Google Scholar
MacRae, J. C. & Armstrong, D. G. (1969). Br. J. Nufr. 23, 15.Google Scholar
Morgenstern, S., Flor, R.V., Kaufman, J. H. & Klein, B. (1966). Clin. Chem. 12, 748.CrossRefGoogle Scholar
Peers, D. G. (1977). Proc. Nutr. Soc. 36, 63A.Google Scholar
Portmann, P. (1957). Z. Physiol. Chcm. 309, 87.CrossRefGoogle Scholar
Smith, R. C., Moussa, N. M. & Hawkins, G. E. (1974). Br. J. Nutr. 32, 529.CrossRefGoogle Scholar
Smith, R. H..& McAllan, A. B. (1966). Br. J. Nutr. 20, 703.CrossRefGoogle Scholar
Smith, R. H. & McAllan, A. B. (1971). Br. J. Nutr. 25, 181.CrossRefGoogle Scholar
Smith, R. H., McAllan, A. B., Hewitt, D. & Lewis, P. L. (1978). J. agric. Sci., Camb. 90, 557.Google Scholar
Thill, N., Francois, E., Thewis, A. & Thielemans, M.-F. (1978). Ann. Zootech. 27, 363.CrossRefGoogle Scholar
Toofanian, F. & Teshfarn, M. (1978). Res. Vet. Sci. 24, 382.Google Scholar
Topps, J. H. & Elliott, R. C. (1965). Nature, Lond. 205, 498.CrossRefGoogle Scholar
Williams, A. P. & Smith, R. H. (1974). Br. J. Nutr. 32, 421.CrossRefGoogle Scholar
Wilson, D.W. & Wilson, H. C. (1962). J. biol. Chem. 237, 1643.Google Scholar
Wilson, T. H. & Wilson, D. W. (1958). J. biol. Chem. 233, 1544.CrossRefGoogle Scholar
Young, E. G. & Conway, C. F. (1942). J. biol. Chem. 142, 839.CrossRefGoogle Scholar
Zittle, C. A. (1946). J. biol. Chem. 166, 499.CrossRefGoogle Scholar