Two-year crossbreeding experiment involving Baladi Saudi (S) and White Leghorn (L) chickens was carried out in El-Qassim region in Saudi Arabia to evaluate the egg component traits of the resulting crossbreds. A random sample of 1989 eggs for egg weight (EW), albumen weight (AW), yolk weight (YW) and shell weight (SW) were used. Variance components, heritabilities and genetic and environmental correlations for the egg traits were estimated using DFREML procedure of multi-trait animal model. The genetic model of Dickerson under multi-trait animal model was used to estimate the crossbreeding components of this experiment in terms of direct (G') and maternal (GM) additive effects and direct (H') heterosis. Hens of L breed showed higher qualities of eggs compared to the S hens. Estimates of heritability were moderate and ranged from 0.22 to 0.29. All estimates of genetic correlations among egg components were high and ranged from 0.53 to 0.93. The direct additive effects considerably affected all egg traits. L-sired hens had high direct additive effects (GI) compared to the S-sired hens for all traits studied. Maternal additive effects (GM) for all traits were considerable and in favour of the L breed. The percentages of GI for egg components ranged from 8.2 to 11.7, while percentages of G" ranged from 4.7 to 9.8%. Crossbred hens recorded negative estimates of HI for most egg component traits since these percentages ranged from 7.0 to 1.2%.
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