Hostname: page-component-848d4c4894-cjp7w Total loading time: 0 Render date: 2024-06-14T13:00:36.586Z Has data issue: false hasContentIssue false

Changes in genetic parameters under restricted index selection

Published online by Cambridge University Press:  14 April 2009

Suzanne I. Mortimer
Affiliation:
School of Wool and Pastoral Sciences, The University of New South Wales, Kensington, N.S.W., 2033, Australia
J. W. James
Affiliation:
School of Wool and Pastoral Sciences, The University of New South Wales, Kensington, N.S.W., 2033, Australia

Summary

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.

The ability of restricted selection indices to prevent genetic change in a restricted trait over several generations of selection was studied using deterministic computer models. Four loci, two affecting each trait independently, and two pleiotropic loci, one affecting each trait in the same direction, and one with opposite effects, were modelled. In general, continued effectiveness of the restriction was achieved only when the restricted trait was affected by only one locus. In some conditions (equal gene frequencies), an independent locus and one pleiotropic locus affecting the restricted trait allowed maintenance of the restriction. The results suggest that long-term restriction may be very difficult without re-estimation of parameters.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1987

References

Abplanalp, H., Ogasawara, F. X. & Asmundson, V. S. (1963). Influence of selection for body weight at different ages on growth of turkeys. British Poultry Science 4, 7180.CrossRefGoogle Scholar
Bohren, B. B., Hill, W. G. & Robertson, A. (1966). Some observations on asymmetrical correlated responses to selection. Genetical Research 7, 4457.CrossRefGoogle ScholarPubMed
Eisen, E. J. (1977). Restricted selection index: an approach to selecting for feed efficiency. Journal of Animal Science 44, 958972.Google Scholar
Famula, T. R. (1984). Restricted best linear unbiased prediction and a selection model. Theoretical and Applied Genetics 67, 337340.CrossRefGoogle Scholar
Latter, B. D. H. (1965). The response to artificial selection due to autosomal genes of large effect. 1. Changes in gene frequency at an additive locus. Australian Journal of Biological Sciences 18, 585598.Google Scholar
McCarthy, J. C. & Doolittle, D. P. (1977). Effects of selection for independent changes in two highly correlated body weight traits of mice. Genetical Research 29, 133145.Google Scholar
Morley, F. H. W. (1955). Selection for economic characters in Australian Merino sheep. V. Further estimates of phenotypic and genetic parameters. Australian Journal of Agricultural Research 6, 7790.Google Scholar
Mortimer, S. I. (1984). Efficiency of multiple-trait selection methods with and without restrictions. Ph.D. Thesis. University of New South Wales.Google Scholar
Scheinberg, E., Bell, A. E. & Anderson, V. L. (1967). Genetic gain in populations of Tribolium castaneum under uni-stage tandem selection and under restricted selection indices. Genetics 55, 6990.Google Scholar