Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-23T15:51:09.219Z Has data issue: false hasContentIssue false
  • English
  • Français

A study of the protein requirements of the mature breeding ewe

Maintenance requirement of the non-pregnant ewe

Published online by Cambridge University Press:  09 March 2007

J. J. Robinson  and
T. J. Forbes
J. J. Robinson
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough and The Queen's University of Belfast
T. J. Forbes
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough and The Queen's University of Belfast
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. An experiment was carried out to study more precisely by nitrogen balance techniques the intake of digestible crude protein required for maintenance in the mature non-pregnant ewe. 2. Four isocaloric diets supplying adequate energy, approximately 90 kcal/kg W0.73 metabolizable energy daily, and differing in crude protein content were each given to eight individually penned ewes. The diets provided 2.4, 4.9, 7.7 and 9.5 g digestible N per ewe per day. 3. The average weight of the ewes was 57.4 kg. They were rationed according to metabolic body-weight (W0.73) at a rate of approximately 800 g dry matter per 50 kg ewe per day for a 4-week period before N balance studies were carried out over an 8-day collection period. 4. The mean apparent digestibilities of dry matter were 67.3±0.8, 68.1±0.7, 70.9±1.0 and 68.8±0.8 respectively. The apparent digestibilities of N, increasing with increasing N intake, were 30.6±2.1, 46.3±2.1, 58.2±0.6 and 61.5±1.3 respectively. 5. The intake of apparently digested N required for maintenance was calculated in three ways, from the regressions of apparently digested N on N retention or on urinary N and from the underlying relationship between N retention and urinary N. The estimates so obtained were respectively 0.185±0.037, 0.148±0.020 and 0.150±0.020 g N per kg W0.78 per day, corresponding to 1.16, 0.93 and 0.94 g apparently digestible crude protein per kg W0.73 per day. 6. Metabolic faecal N, determined by the extrapolation method, was 0.629±0.047 g/100 g dry matter consumed. 7. The results are discussed in relation to practical feeding standards and other research findings.

Type
Research Article
Information
British Journal of Nutrition , Volume 20 , Issue 2 , May 1966 , pp. 263 - 272
Copyright
Copyright © The Nutrition Society 1966

References

REFERENCES

Allison, J. B. (1956). Am. J. clin. Nutr. 4, 662.CrossRefGoogle Scholar
Armstrong, D. G., Blaxter, K. L. & Graham, N. McC. (1957). Br. J. Nutr. 11, 392.CrossRefGoogle Scholar
Blaxter, K. L. (1962 a). Br. J. Nutr. 16, 615.CrossRefGoogle Scholar
Blaxter, K. L. (1962 b). The Energy Metabolism of Ruminants, p. 233. London: Hutchinson.Google Scholar
Blaxter, K. L. (1964). Proc. Nutr. Soc. 23, 62.CrossRefGoogle Scholar
Blaxter, K. L. & Mitchell, H. H. (1948). J. Anim. Sci. 7, 351.CrossRefGoogle Scholar
Brody, S. (1945). Bioenergetics and Growth. New York: Reinhold Publishing Corp.Google Scholar
Chalmers, M. I. (1961). In Digestive Physiology and Nutrition of the Ruminant, p. 205. [D, Lewis, editor.] London: Butterworths.Google Scholar
Chalmers, M. I., Cuthbertson, D. P. & Synge, R. L. M. (1954). J. agric. Sci., Camb., 44, 254.CrossRefGoogle Scholar
Davies, O. L. (1957). Statistical Methods in Research and Production, p. 173. London: Oliver and Boyd.Google Scholar
Duncan, D. B. (1955). Biometrics, 11, 1.CrossRefGoogle Scholar
Elliott, R. C. & Topps, J. H. (1963). Br. J. Nutr. 17, 539.CrossRefGoogle Scholar
Elliott, R. C. & Topps, J. H. (1964). Br. J. Nutr. 18, 245.CrossRefGoogle Scholar
Harris, L. E. & Mitchell, H. H. (1941). J. Nutr. 22, 167.CrossRefGoogle Scholar
Head, M. J. (1953). J. agric. Sci. Camb., 43, 2815.Google Scholar
Head, M. J. & Murdoch, J. C. (1965). J. Br. Grassl. Soc. 20, 106.CrossRefGoogle Scholar
Hutchinson, K. J. (1958). Aust. J. agric. Res. 9, 508.CrossRefGoogle Scholar
Langlands, J. P., Corbett, J. L., McDonald, I. & Pullar, J. D. (1963). J. Anim. Prod. 5, 1.Google Scholar
Lewis, D. (1957). J. agric. Sci. Camb., 48, 438.CrossRefGoogle Scholar
McDonald, I. W. (1952). Biochem. J. 51, 86.CrossRefGoogle Scholar
Marston, H. R. (1948). Aust. J. scient. Res. 1, 93.Google Scholar
Mitchell, H. H. (1962). Comparative Nutrition of Man and Domestic Animals. Vol. 1, p. 167. New York and London: Academic Press Inc.Google Scholar
National Research Council (1957). Publs natn. Res. Coun., Wash., no. 504.Google Scholar
Packett, L. V. & Groves, T. D. D. (1965). J. Anim. Sci. 24, 341.CrossRefGoogle Scholar
Phillipson, A. T. (1959). Scientific Principles of Feeding Farm Livestock, p. 117. London: Farmer and Stock-Breeder Publications Ltd.Google Scholar
Phillipson, A. T., Dobson, N. J., Blackburn, T. H. & Brown, M. (1962). Br. J. Nutr. 16, 157.CrossRefGoogle Scholar
Reid, R. L. & Mills, S. C. (1962). Aust. J. agric. Res. 13, 282.CrossRefGoogle Scholar
Schmidt-Nielsen, B. & Osaki, H. (1958). Am. J. Physiol. 193, 657.CrossRefGoogle Scholar
Somers, M. (1961). Aust. J. exp. Biol. med. Sci. 39, 145.CrossRefGoogle Scholar
Sotola, J. (1930). J. agric. Res. 40, 79.Google Scholar
Tagari, H., Dror, Y., Ascarelli, I. & Bondi, A. (1964). Br. J. Nutr. 18, 333.CrossRefGoogle Scholar
Thomson, W. & Aitken, F. C. (1959). Tech. Commun. Commonw. Bur. Anim. Nutr. 20.Google Scholar
Turk, T. L. & Morrison, F. B. & Maynard, L. A. (1934). J. agric. Res. 48, 555.Google Scholar