Descriptive statistics of egg production traits for F₂ chickens.

1: EN1, egg number in the pre-peak laying period from 21 to 26 weeks of age; EN2, egg number in the peak laying period from 27 to 36 weeks of age; EN3, egg number in the persistent laying period from 37 to 72 weeks of age; EN4, egg number from 37 to 47 weeks of age; EN5, egg number from 48 to 72 weeks of age; EN21-40, egg number from 21 to 40 weeks of age; EN21-56, egg number from 21 weeks of age to 56 weeks of age; EN21-72, egg number from 21 to 72 weeks of age; LR, egg laying rate from 25 to 40 weeks of age; AFE, age at first egg. 2: Number of birds that pass the quality control of phenotypic value. 3: Coefficient of variation. Descriptive statistics of egg production traits for F2 chickens.