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Changes in body composition relative to weight and maturity in large and small strains of Australian Merino rams 1. Muscle, bone and fat

Published online by Cambridge University Press:  02 September 2010

R. M. Butterfield ,
D. A. Griffiths ,
J. M. Thompson ,
J. Zamora  and
A. M. James
R. M. Butterfield
Affiliation:
Department of Veterinary Anatomy, University of Sydney, NSW, 2006, Australia
D. A. Griffiths
Affiliation:
Division of Mathematics and Statistics, CSIRO Lindfield, NSW, 2070, Australia
J. M. Thompson
Affiliation:
Department of Veterinary Anatomy, University of Sydney, NSW, 2006, Australia
J. Zamora
Affiliation:
Department of Veterinary Anatomy, University of Sydney, NSW, 2006, Australia
A. M. James
Affiliation:
Department of Veterinary Anatomy, University of Sydney, NSW, 2006, Australia
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Abstract

Maturing patterns of carcass muscle, bone and fat were established using dissection data from 20 large mature size strain and 19 small mature size strain Merino rams. The rams were fed a pelleted ration soon after weaning and individual rams from both strains slaughtered at 6 kg increments in live weight from 18 kg to maturity at 116 and 91 kg for the large and small strains respectively.

Composition of mature rams of both strains was similar for the proportion of muscle and bone but there was a slightly greater proportion of fat in the larger strain.

The progress of each carcass tissue to maturity was assessed relative to progress of shorn full live weight to maturity. Maturing patterns of the three carcass tissues were not significantly different in the two strains. Muscle and bone were early maturing relative to live weight and fat late maturing.

The composition of the large and small mature size strains at the same live weight and at the same proportion of maturity was predicted from the maturity patterns of the carcass tissues and the composition of the mature rams. At the same live weight the large mature size strain had a greater proportion of bone and a smaller proportion of fat than the small mature size strain. At the same proportion of mature live weight, differences between the strains in proportional composition were reduced, and the large mature size strain had slightly more fat.

Some guidelines for comparison of strains of animals of different mature size are developed.

Type
Research Article
Information
Animal Production , Volume 36 , Issue 1 , February 1983 , pp. 29 - 37
Copyright
Copyright © British Society of Animal Science 1983

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References

REFERENCES

Brinks, J. S., Clark, R. T., Kieffer, N. M. and Urick, J. J. 1964. Estimates of genetic, environmental and phenotypic parameters in range Hereford females. J. Anim. Sci. 23: 711–716.CrossRefGoogle Scholar
Butterfiled, R. M. and May, N. D. S. 1966. Muscles of the Ox. University of Queensland Press, Brisbane.Google Scholar
Fourie, P. D., Kirton, A. H. and Jury, K. E. 1970. Growth and development of sheep. II. Effect of breed and sex on the growth and carcass composition of the Southdown and Romney and their cross. N. Z. Jl agric. Res. 13: 753–770.CrossRefGoogle Scholar
Graham, N. McC. and Searle, T. W. 1972. Balances of energy and matter in growing sheep at several ages, body weights and planes of nutrition. Aust. J. agric. Res. 23: 97–108.CrossRefGoogle Scholar
Mcclelland, T. H., Bonatti, B. and Taylor, St C. S. 1976. Breed differences in body composition of equally mature sheep. Anim. Prod. 23:281–293.Google Scholar
Pomeroy, R. W. 1978. Historical and general review of growth and development. In Current Topics in Veterinary Medicine. Vol. 2. Patterns of Growth and Development in Cattle (ed. Boer, H. de and Martin, J.), pp. 3–11. Martinus Nijhoff, The Hague.CrossRefGoogle Scholar
Roberts, R. C. 1979. Side effects of selection for growth in laboratory animals. Livest. Prod. Sci. 6: 93–104.CrossRefGoogle Scholar
Taylor, St C. S. 1968. Genetic variation in growth and development of cattle. In Growth and Development of Mammals (ed. Lodge, G. A. and Lamming, G. E.), pp. 267–290. Butterworth, London.Google Scholar
Tulloh, N. M. 1964. The carcase composition of sheep, cattle and pigs as functions of body weight. In Carcase Composition and Appraisal of Meat Animals (ed. Tribe, D. E.), pp. 5–16. CSIRO, Melbourne.Google Scholar
Widdowson, E. M. 1980. Definitions of growth. In Growth in Animals (ed. Lawrence, T. L. J.), pp. 1–9. Butterworth, London.Google Scholar
Williams, E. J. 1959. Regression Analysis. Wiley, New York.Google Scholar
Wood, J. D., Macfie, H. J. H., Pomeroy, R. W. and Twinn, D. J. 1980. Carcass composition in four sheep breeds: the importance of type of breed and stage of maturity. Anim. Prod. 30: 135–152.Google Scholar