Hostname: page-component-848d4c4894-2xdlg Total loading time: 0 Render date: 2024-06-29T13:08:44.127Z Has data issue: false hasContentIssue false
  • English
  • Français

Evaluation of modified [35S]methionine and [35S]casein preparations as supplements for sheep

Published online by Cambridge University Press:  09 March 2007

A. M. Downes ,
P. J. Reis ,
L. F. Sharry  and
D. A. Tunks
A. M. Downes
Affiliation:
CSIRO Division of Animal Physiology, Ian Clunies Ross Animal Research Laboratory, Prospect, NS W 2149, Australia
P. J. Reis
Affiliation:
CSIRO Division of Animal Physiology, Ian Clunies Ross Animal Research Laboratory, Prospect, NS W 2149, Australia
L. F. Sharry
Affiliation:
CSIRO Division of Animal Physiology, Ian Clunies Ross Animal Research Laboratory, Prospect, NS W 2149, Australia
D. A. Tunks
Affiliation:
CSIRO Division of Animal Physiology, Ian Clunies Ross Animal Research Laboratory, Prospect, NS W 2149, Australia
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. Doses of L-[35S]methionine (2 g) and [35S]casein (20 g) were given to sheep in the diet or via the abomasum, and the patterns of 35S-labelling in blood, wool and excreta were studied during the 7 d following administration of the dose.

2. Doses given via the abomasum resulted in substantial labelling of the plasma proteins and wool; only small amounts of the dose were recovered in the urine and faeces. In contrast, doses given in the diet resulted in much less labelling of plasma proteins and wool and ingreater losses in excreta. These results provide the basis of a rapid system for testing the effectiveness of various methods of protecting methionine and casein from degradation in the rumen.

3. From the patterns obtained with N-formyl-DL-[35S]methionine and [35S]polymethionine (mol. wt 7–8 × 104) it appears unlikely that these compounds would stimulate wool growth if given as dietary supplements.

4. [35S]Casein which had been treated with an 8 % aqueous solution of formaldehyde gave results which showed that the casein had been protected from destruction in the rumen without markedly reducing its subsequent digestibility. Treatment of [35S]casein with excess, formalde-hyde (a 40 % aqueous solution) gave a product which was completely indigestible.

5. It is concluded that the radioisotope technique could be applied to other [35S]amino acids or their derivatives and to other [35S]proteins, and should also be applicable to larger ruminants such as cattle.

Type
Research Article
Information
British Journal of Nutrition , Volume 24 , Issue 4 , December 1970 , pp. 1083 - 1089
Copyright
Copyright © The Nutrition Society 1970

References

REFERENCES

Askonas, B. A., Campbell, P. N. & Work, T. S. (1954). Biochem. J. 58, 326.CrossRefGoogle Scholar
Block, R. J. & Bolling, D. (1951). The Amino Acid Composition of Proteins and Foods. Analytical Methods and Results 2nd ed.Springfield, Ill.: C. C. Thomas.Google Scholar
Bloom, S. M., Fasman, G. D., de Lozé, C. & Blout, E. R. (1962). J. Am. chem. Soc. 84, 458.CrossRefGoogle Scholar
Colebrook, W. F., Ferguson, K. A., Hemsley, J. A., Hogan, J. P., Reis, P. J. & Weston, R. H. (1968). Proc. Aust. Soc. Anim. Prod. 7, 397.Google Scholar
Downes, A. M. (1961). Aust. J. biol. Sci. 14, 427.CrossRefGoogle Scholar
Downes, A. M. & Till, A. R. (1963). Nature, Lond. 197, 449.CrossRefGoogle Scholar
Dunn, M. S. (1949). Biochem. Prep. 1, 22.Google Scholar
Du Toit, P. J., Malan, A. I., Groenewald, J. W. & Botha, M. L. (1935). Onderstepoort J. vet. Sci. Anim. Ind. 4, 229Google Scholar
Ferguson, K. A., Hemsley, J. A. & Reis, P. J. (1967). Aust. J. Sci. 30, 215.Google Scholar
Greenstein, J. P. & Winitz, M. (1961). The Chemistry of the Amino Acids Vol. 2, p. 9s21. New York: Wiley.Google Scholar
Kalberer, F. & Rutschmann, J. (1961). Helv. chim. Acta. 4, 1956.CrossRefGoogle Scholar
McDonald, I. W. (1969). In International Encyclopedia of Food and Nutrition Vol 17, part I, p. 87 ‘Cuthbertson, D., editor’. Oxford: Pergamon Press.Google Scholar
McDonald, I. W. & Hall, R. J. (1957). Biochem. J. 67, 400.CrossRefGoogle Scholar
Marston, H. R. (1932). Aust. J. exp. Biol. med. Sci. 9, 235.CrossRefGoogle Scholar
Patterson, M. S. & Greene, R. C. (1965). Analyt. Chem. 37, 854.CrossRefGoogle Scholar
Reis, P. J. (1967). Aust. J. biol Sci. 20, 809.Google Scholar
Reis, P. J. (1969). Aust. J. biol. Sci. 22, 745.CrossRefGoogle Scholar
Reis, P. J. & Schinckel, P. G. (1963). Aust. J. biol. Sci. 16, 218.Google Scholar
Reis, P. J. & Schinckel, P. G. (1964). Aust. J. biol. Sci. 17, 532.CrossRefGoogle Scholar
Reis, P. J. & Tunks, D. A. (1969). Aust. J. agric. Res. 20, 775.CrossRefGoogle Scholar