Genetic analysis of egg quality in selected and control lines of Japanese quails

Body weight, egg production and egg quality traits of two selected strains (PQ1 and PQ2) and a control line (PQ3) of Japanese quails, comprising a total of 750 females which were the progeny of 114 sires, were recorded upto 16 weeks of age. Selected strains were significantly heavier than control line at 16 weeks of age. The selected strains, as compared to the unselected control line, had more egg weight, yolk weight, albumen weight and lower egg production. The heritability estimates, pooled over the three lines, were high for body weight, egg weight, albumen weight and egg number (0.51±0.13 to 0.87±0.16), moderate for yolk weight, specific gravity, albumen height, Haugh Unit Score (0.26±0.1 0 to 0.43±0.12) and low for % yolk albumen and shell weight (0.11±0.09 to 0.20±0.11). Body weight at 4 and 16 weeks of age had low positive genetic and phenotypic correlations with egg weight, yolk weight, albumen weight, albumen height and shell weight and specific gravity. The correlations between egg number and egg weight and its components were very low and negative. The genetic and phenotypic correlations between egg weight and its components were positive and high.