ESTIMATES OF (CO) VARIANCE COMPONENTS FOR DIRECT AND MATERNAL EFFECTS ON BIRTH WEIGHT OF EGYPTIAN BARKI LAMBS

Document Type : Original Article

Authors

Animal and Poultry Breeding Dept., Desert Research Centre, ElMatareya, Cairo, Egypt

Abstract

The  present study was undertaken to estimate (co) variance components for birth weight (BW) of Barki lamb's. The models fitted included direct genetic, maternal genetic and direct-maternal genetic co-variance and maternal permanent environmental effects using six forms of animal models (MTDFREML). Data and pedigree information of the studied Barki sheep were collected from 1994 to 2001. A direct heritability estimate of 0.12 and maternal heritability estimate of 0.21 were obtained for BW. Maternal permanent environmental effect was found to be 0.092 with little  contribution on BW. The estimate of the direct- maternal correlation was high and positive. Results indicated that the inclusion of maternal effects in genetic evaluation of early growth traits in Barki lambs were significant and need to be considered in any selection program to improve Barki sheep.