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Inbreeding – lessons from animal breeding, evolutionary biology and conservation genetics

Published online by Cambridge University Press:  09 March 2007

T. N. Kristensen
Affiliation:
Department of Genetics and Biotechnology, Danish Institute of Agricultural Sciences, PO Box 50, DK-8830 Tjele, Denmark Aarhus Centre for Environmental Stress Research (ACES), Department of Ecology and Genetics, University of Aarhus, Building 540, Ny Munkegade, DK-8000 Aarhus C, Denmark
A. C. Sørensen*
Affiliation:
Department of Genetics and Biotechnology, Danish Institute of Agricultural Sciences, PO Box 50, DK-8830 Tjele, Denmark Institute of Production Animals and Horses, The Royal Veterinary and Agricultural University, Ridebanevej 12, DK-1870 Frederiksberg C, Denmark
*
Corresponding author. E-mail: [email protected]
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Abstract

Abstract Increased rates of inbreeding are one side effect of breeding programmes designed to give genetic progress for traits of economic importance in livestock. Inbreeding leads to inbreeding depression for traits showing dominance, and will ultimately lead to a decrease in genetic variance within populations. Here we review theoretical and experimental literature from animal breeding, evolutionary biology and conservation genetics on the consequences of inbreeding in terms of trait means and genetic and environmental variance components. The genetic background for these effects is presented and the experimental literature interpreted in relation to them. Furthermore, purging of deleterious alleles and the variable nature of effects of inbreeding on populations are discussed. Based on the literature, we conclude that inbreeding in animal breeding must be controlled very efficiently to maintain long-term sustainable livestock production in the future. The tools to do this efficiently exist, and much can be learnt on inbreeding from the literature in fields only distantly related to animal breeding.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 2005

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