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Genetic heterogeneity of residual variance within families for body weight in poultry

Published online by Cambridge University Press:  23 November 2017

S.J. Rowe*
Affiliation:
School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, U.K.
I.M.S. White
Affiliation:
School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, U.K.
S. Avendano
Affiliation:
Aviagen, Newbridge, Midlothian, Edinburgh EH28 8SZ, U.K.
W.G. Hill
Affiliation:
School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, U.K.
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Extract

In classical quantitative genetic models, phenotypic value depends on genotype, but phenotypic variation among individuals of the same genotype is assumed to be the same for all genotypes. ANOVA and other statistical tests are underpinned by the assumption of a multivariate normal distribution with homogenous variances and independent normally distributed deviations. Heterogeneity of phenotypic or environmental variance has been estimated in dairy cattle (Brotherstone and Hill, 1986). Models and analyses developed by SanChristobal et al. (1998) and Sorenson and Waagepeterson (2003) provide strong evidence for litter size in pigs of heterogeneity of residual variance under genetic control. Environmental sensitivity dependent upon genotype has implications for livestock production, and may explain phenomena such as plasticity and canalisation. The aim was to calculate variability in within family variance among large half sib broiler families, in order to test for the presence of and quantify heterogeneity in residual variation amongst genotypes.

Type
Theatre Presentations
Copyright
Copyright © The British Society of Animal Science 2005

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References

Brotherstone, S. and Hill, W.G. 1986. Heterogeneity of variance amongst herds for milk production. Animal Production 42: 297303.Google Scholar
Hill, W.G. 2004. Heterogeneity of genetic and environmental variance of quantitative traits. Journal of Indian Society of Agricultural Statistics 42: 4963.Google Scholar
SanCristobal–Gaudy, M., Elsen, J.M., Bodin, L. and Chevalet, C. 1998. Prediction of the response to a selection for canalisation of a continuous trait in animal breeding. Genetics Selection Evolution 42: 423451.CrossRefGoogle Scholar
Sorenson, D. and Waagepeterson, R. 2003. Normal Linear Models with genetically structured residual variance heterogeneity: a case study. Genetical Research 42: 207222.CrossRefGoogle Scholar