Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-19T13:34:45.657Z Has data issue: false hasContentIssue false
  • English
  • Français

The effects of selection on sex differences in pre-weaning growth in beef cattle

Published online by Cambridge University Press:  02 September 2010

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

Summary

Pre-weaning growth data from 3822 calves reared in 11 Victorian herds were analysed. The results suggested that the superiority of males (bulls) over castrated males (steers) in pre-weaning growth was due, at least partly, to the early castration of poorly growing male calves, i.e. to the effects of early selection. The extent of this selection bias was further examined using results from similar studies and from experiments in which bulls and steers were selected without bias. These studies strongly supported the view that the superiority of bulls over steers was primarily due to selection and not to sex effects. If sex did influence the bull-steer difference it was of no statistical or practical importance.

In the Victorian data, the ratio of bulls to steers was higher in subclasses in which average growth rates were higher. When selection effects are correlated in this way with other environmental effects such as age of dam effects further biases may arise in estimation of those effects and hence in individual or mass selection.

The results indicated, therefore, that unless bulls and steers are treated as one sex biases can arise in both individual selection and progeny selection.

Type
Research Article
Information
Animal Production , Volume 25 , Issue 1 , August 1977 , pp. 39 - 45
Copyright
Copyright © British Society of Animal Science 1977

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bailey, C. M., Probert, C. L. and Bohman, V. R. 1966. Growth rate, feed utilization and body composition of young bulls and steers. J. Anim. Sci. 25: 132–137.CrossRefGoogle ScholarPubMed
Brannang, E. 1966. Studies on monozygous cattle twins. XVIII. The effect of castration and age of castration on the growth rate, feed conversion and carcase traits of Swedish Red and White Cattle. Parti. LantbrHogsk. Annlr 32: 329–415.Google Scholar
Brinks, J. S., Clark, R. T., Rice, F. J. and Kieffer, N. M. 1961. Adjusting birth weight, weaning weight, and preweaning gain for sex of calf in range Hereford cattle. J. Anim. Sci. 20: 363–367.Google Scholar
Burgess, J. B., Landblom, N. L. and Stonaker, H. H. 1954. Weaning weights of Hereford calves as affected by inbreeding, sex, and age. J. Anim. Sci. 13: 843–851.CrossRefGoogle Scholar
Cobic, T. 1968. Castration experiments with Yugoslav Simmental cattle. I. The effect of castration on growth and live-weight gains. Anim. Prod. 10: 103–107.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: 972–982.CrossRefGoogle Scholar
Flower, A. E., Brinks, J. S., Urick, J. J. and Willson, F. S. 1963. Comparisons of inbred lines and linecrosses for performance traits in Hereford range cattle. J. Anim. Sci. 22: 914–918.CrossRefGoogle Scholar
Harte, F. J. 1969. The production of beef from young bulls. III. Ir. J. agric. Res. 8: 293–305.Google Scholar
Harte, F. J. and Curran, S. 1967. The production of beef from young bulls. II. Ir. J. agric. Res. 6: 101–118.Google Scholar
Harvey, W. R. 1960. Least squares analysis of data with unequal sub-class numbers. United States Department of Agriculture, ARS-20–8 (Mimeograph).Google Scholar
Hopkins, I. R. 1974. The effect of various environmental factors on rate of liveweight gain in beef herds in Victoria. M.S. Thesis, Univ. Melbourne.Google Scholar
Jeffrey, H. B., Berg, R. T. and Hardin, R. T. 1971. Factors affecting preweaning performance in beef cattle. Can. J. Anim. Sci. 51: 561–577.CrossRefGoogle Scholar
Joubert, D. M. and Dreyer, J. H. 1965. Bull versus steer on a moderate plane of nutrition in a group-feeding trial. Proc. S. Afr. Soc. Anim. Prod. 4: 151–154.Google Scholar
Kellaway, R. C. 1971. Growth, fertility and carcass studies with bulls, induced cryptor- chids and steers. Aust. J. exp. Agric. Anim. Husb. 11: 599–603.CrossRefGoogle Scholar
Kennedy, J. F. and Chirchir, G. I. K. 1971. A study of the growth rate of F2 and F3 Africander cross, Brahman cross and British cross cattle from birth to 18 months old in a tropical environment. Aust. J. Exp. Agric. Anim. Husb. 11: 593–598.CrossRefGoogle Scholar
Koch, R. M., Gregory, K. E., Ingalls, J. E. and Arthaud, R. L. 1959. Evaluating the influence of sex on birth weight and pre-weaning gain in beef cattle. J. Anim. Sci. 18: 738–744.CrossRefGoogle Scholar
Lehmann, R. P., Gaines, J. A., Carter, R. C., Bovard, K. P. and Kincaid, C. M. 1961. Selection indexes for weanling traits in beef calves. J. Anim. Sci. 20: 53–57.CrossRefGoogle Scholar
Marlowe, T. J., Mast, C. C. and Schalles, R. R. 1965. Some nongenetic influences on calf performance. J. Anim. Sci. 24: 494–501.CrossRefGoogle ScholarPubMed
Pilkington, D. H., Walters, L. E. and Pope, L. S. 1959. Carcass studies with steers, bulls and stilbestrol-implanted bulls sold as slaughter calves. J. Anim. Sci. 18: 1154 (Abstr.).Google Scholar
Preston, T. R., MacDearmid, A., Aitken, J. N., MacLeod, N. A. and Philip, E. B. 1968. [The effect of castration on growth, feed conversion and carcass quality of Friesian male cattle given all-concentrate diets.] Revta cub. Cienc. agric. 2: 183–190.Google Scholar
Price, M. A. and Yeates, N. T. M. 1971. Infertile bulls versus steers. I. The influence of level of nutrition on relative growth rate. J. agric. Sci., Comb. 77: 307–311.CrossRefGoogle Scholar
Sewell, H. B., Comfort, J. E., Day, B. N. and Lasley, J. F. 1963. Genetic and environmental factors influencing the weaning weight of beef calves. Res. Bull. Mo. agric. Exp. Stn, No. 823.Google Scholar
Vernon, E. H., Harvey, W. R. and Warwick, E. J. 1964. Factors affecting weight and score of crossbred-type calves. J. Anim. Sci. 23: 21–27.CrossRefGoogle Scholar
Warren, E. P., Thrift, F. A. and Carmon, J. L. 1965. Estimates of the effects of certain environmental factors on weaning weights of Georgia beef calves. Tech. Bull. Ga agric. Exp. Stns, No. 47.Google Scholar
Watson, M. J. 1969. The effects of castration on the growth and meat quality of grazing cattle. Aust. J. Exp. Agric. Anim. Husb. 9: 164–171.CrossRefGoogle Scholar