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Cumulative selection differentials and realized heritabilities with overlapping generations

Published online by Cambridge University Press:  02 September 2010

J. W. James
J. W. James
Affiliation:
Institute of Animal Genetics, West Mains Road, Edinburgh EH9 3JN
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Abstract

It is shown that a commonly used method of calculating cumulative selection differentials in experiments where generations overlap is biased, and consequently leads to biased estimates of realized heritability. In one example, the heritability was underestimated by about one-fifth. Since genetic variation in a given progeny crop may be increased by genetic differences between parental age groups, realized heritability estimated by regression may not agree with base population estimates. An alternative form of analysis is proposed to allow for this effect.

Type
Research Article
Information
Animal Production , Volume 42 , Issue 3 , June 1986 , pp. 411 - 415
Copyright
Copyright © British Society of Animal Science 1986

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References

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