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Effect of sampling errors on efficiency of selection indices. 2. Use of information on associated traits for improvement of a single important trait

Published online by Cambridge University Press:  02 September 2010

Jill Sales  and
W. G. Hill
Jill Sales
Affiliation:
Institute of Animal Genetics, Edinburgh EH9 3JN
W. G. Hill
Affiliation:
Institute of Animal Genetics, Edinburgh EH9 3JN
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Summary

An analysis is undertaken of the effect of errors in estimates of parameters on the response to selection for an economically important trait (trait 1) when one or more additional traits are added in a selection index. The detailed analysis is confined to one additional trait (trait 2) which contributes useful information unless the genetic and phenotypic regressions of trait 1 on trait 2 are equal.

If there are errors in parameter estimates the extra response obtained by including trait 2 will usually be over-predicted. When trait 2 actually contributes no useful information the predicted benefit equals the real loss in efficiency from its inclusion.

The loss in efficiency from poor estimation of parameters, whether or not the second trait makes a contribution, is roughly one-quarter of the squared coefficient of variation of a heritability estimate of trait 1 in the same experiment.

Type
Research Article
Information
Animal Production , Volume 23 , Issue 1 , August 1976 , pp. 1 - 14
Copyright
Copyright © British Society of Animal Science 1976

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References

REFERENCES

Gjedrem, T. 1967. Selection indexes compared with single trait selection. I. The efficiency of including correlated traits. Ada Agric. scand. 17: 17–263.Google Scholar
Harris, D. L. 1964. Expected and predicted progress from index selection involving estimates of population parameters. Biometrics 20: 20–46.CrossRefGoogle Scholar
Hartley, H. O. and Harris, D. L. 1963. Monte Carlo computations in normal correlation problems. J. Ass. comput. Mach. 10: 10–302.CrossRefGoogle Scholar
Mao, I. L. 1971. The effect of parameter estimation errors on the efficiency of index selection and on the accuracy of genetic gain prediction. Ph.D. Thesis, Cornell Univ., Ithaca, New York.Google Scholar
Miller, R. G. 1974. Thejackknif—a review. Biometrika 61: 61–1.Google Scholar
Neimann-Sørensen, A. and Robertson, A. 1961. The association between blood groups. and several production characteristics in three Danish cattle breeds. Acta Agric. scand. 11: 11–163.CrossRefGoogle Scholar
Pig Industry Development Authority. 1965. Combined Testing. Recommendations by the Statistics Section for the Selection Index (Mimeograph). DA 188. Pig Industry Development Authority, London.Google Scholar
Robertson, A. 1959. Experimental design in the evaluation of genetic parameters. Biometrics 15: 15–219.Google Scholar
Sales, J. and Hill, W. G. 1976. Effect of sampling errors on efficiency of selection indices. 1. Use of information from relatives for single trait improvement. Anim. Prod. 22: 22–1.Google Scholar
Smith, C. 1967. Improvement of metric traits through specific genetic loci. Anim. Prod. 9: 349–358.Google Scholar