Effects of genotype and egg weight on hatchability traits and hatching weight in Japanese quail

The effects of genotype and egg weight on hatching weight, fertility, hatchability of fertile eggs and incubated eggs were investigated in Japanese quail. The birds were obtained at an age of 20 weeks from four genetic lines selected for 11 generations for either a high (HL) or a low body weight (LL) at five weeks of age, a randomly bred control line (C) and a layer line (L) selected for egg production over 120 days. Eggs were allocated according to their weight to 13.1 g groups. There was a significant difference between groups in terms of hatching weight, fertility, hatchability of fertile eggs and hatchability of incubated eggs. The highest hatching weights were recorded in the > 13.1 g egg weight group. Genotype affected egg weight significantly, with the highest egg weights recorded in the HL genotype and lowest in the LL genotype. There was a significant positive phenotypic correlation (r = 0.72) between egg weight and hatching weight, and hatching weight increased with an increase in egg weight.