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The effect of level of environment on sex differences in pre-weaning growth rate in beef cattle

Published online by Cambridge University Press:  02 September 2010

I. R. Hopkins
Affiliation:
School of Wool and Pastoral Sciences, University of New South Wales, PO Box 1, Kensington, New South Wales 2033, Australia
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Summary

Using pre-weaning records of 3822 calves from 11 Victorian herds, mean male and female growth rates and corresponding sex differences were calculated for each dam age and herd-year class. From these means simple regression equations relating sex differences and growth rates were calculated. There was a close similarity between equations based on dam age means and those based on herd-year means while correlations between sex differences and male growth rates were high.

These results showed that sex differences and female growth rates could be predicted reliably from the level of environment as measured by male growth rate. Sex differences predicted by these regression relationships differed markedly from those predicted by the simple multiplicative and simple additive models generally used in adjusting for sex differences in selection.

The results also suggested that other differences such as breed differences may be predictable in the same way and that such differences are determined primarily by the level of environment per se rather than differences in the nature of the components contributing to that level.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1977

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References

REFERENCES

Barlow, R., Dettman, E. B. and Williams, L. G. 1974. Non-genetic factors affecting weaning performance of Angus cattle in N.S.W. Proc. Aust. Soc. Anim. Prod. 10th Biennial Conf., pp. 3740.Google Scholar
Creek, M. J. and Nestel, B. L. 1964. Animal production studies in Jamaica. III. The effect of dam age upon the 210-day weights of calves, and the response of male and female calves to different environments. J. agric. Sci., Camb. 62: 165177.CrossRefGoogle Scholar
Cundiff, L. V., Willham, R. L. and Pratt, C. A. 1966. Effects of certain factors and their two-way interactions on weaning weight in beef cattle. J. Anim. Sci. 25: 972982.CrossRefGoogle Scholar
Cunningham, E. P. and Henderson, C. R. 1965. Estimation of genetic and phenotypic parameters of weaning traits in beef cattle. J. Anim. Sci. 24: 182187.CrossRefGoogle Scholar
Hopkins, I. R. 1977. The effects of selection on sex differences in pre-weaning growth in beef cattle. Anim. Prod. 25: 3945.Google Scholar
Linton, A. C., Brinks, J. S., Stonaker, H. H., Sutherland, T. M. and Faulkner, L. C. 1968. Factors affecting weaning weights of cattle. J. Anim. Sci. 27: 1104 (Abstr.).Google Scholar
Marlowe, T. J. and Gaines, J. A. 1958. The influence of age, sex, and season of birth of calf, and age of dam on preweaning growth rate and type score of beef calves. J. Anim. Sci. 17: 706713.CrossRefGoogle Scholar
Marlowe, T. J., Mast, C. C. and Schalles, R. R. 1965. Some nongenetic influences on calf performance. J. Anim. Sci. 24: 494501.CrossRefGoogle ScholarPubMed
Mason, W. E. 1968. Performance recording in Victoria and adjacent regions. M.S. Thesis, Univ. Melbourne.Google Scholar
Pahnish, O. F., Roubicek, C. B., Stanley, E. B., Bogart, R. and Shelby, C. E. 1958. The influence of age of dam on the 270-day weaning weights of bull and heifer calves. Proc. Western Section Am. Soc. Anim. Prod. 9: xlviii.Google Scholar
Pahnish, O. F., Stanley, E. B., Bogart, R. and Roubicek, C. B. 1961. Influence of sex and sire on weaning weights of southwestern range calves. J. Anim. Sci. 20: 454458.CrossRefGoogle Scholar
Rollins, W. C. and Guilbert, H. R. 1954. Factors affecting the growth of beef calves during the suckling period. J. Anim. Sci. 13: 517527.CrossRefGoogle Scholar
Sellers, H. I., Willham, R. L. and de Baca, R. C. 1970. Effect of certain factors on weaning weight of beef calves. J. Anim. Sci. 31: 512.CrossRefGoogle Scholar
Tukey, J. W. 1951. Components in regression. Biometrics 7: 3369.CrossRefGoogle ScholarPubMed