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Genetic and phenotypic parameters for litter traits of D'Man ewes

Published online by Cambridge University Press:  02 September 2010

I. Boujenane
Affiliation:
Department of Animal Production, Hassan II Agronomy and Veterinary Institute, BP 6202 Rabat-Instituts, Morocco
M. Kerfal
Affiliation:
National Institute of Agricultural Research, Errachidia, Morrocco
M. Khallouk
Affiliation:
Livestock Extension Service, ORMVA Tadla, Fquih Ben Salah, Morocco
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Abstract

A total of 1754 records for litter traits of 458 D'man ewes sired by more than 45 rams were analysed to estimate repeatability, heritability and genetic and phenotypic correlations. Repeatability estimated by the intraclass correlation method was 0·11, 0·11, 0·12 and 0·15 for litter sizes at birth and at weaning and litter weights at birth and at weaning, respectively. Paternal half-sib estimates of heritability were 0·09 (s.e. 0·06), 0·04 (s.e. 0·05), 0·15 (s.e. 0·07) and 0·08 (s.e. 0·05), respectively. Genetic correlations among the traits were all positive and varied from 0·17 to 0·72, whereas phenotypic correlations ranged from 0·68 to 0·86.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1991

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