Genetics of hatchability - egg quality from the perspective of a chick

Hatchability is a complex age dependent trait. It comprises of several sub-traits which are susceptible to genetic and environmental factors arising from various sources. This review examines the genetic basis of egg production, fertility and egg quality traits and how these relate with hatchability. We suggest that both sire and dam genetic components are important in overall hatchability mostly because of the significance of these components on fertility and early embryo mortality. The dam that laid the egg was the main source of genetic variation in hatch of fertile eggs, suggesting a huge impact of egg quality traits. The genetic effects (paternal and maternal) were found to vary with the age of the flock.