Genetics of Economic Traits in the Cornell Randombred Control Population

Abstract

Data from the Cornell Randombred Control Population of White Leghorns were analyzed to determine production characteristics in each of two hatches and the different components of genetic variance of economic traits. Birds from hatch 1 were heavier at 8 weeks of age, matured earlier and produced more but smaller eggs with higher albumen score than birds from hatch 2. It was found that additive direct variance was important in determining the variation in the traits studied with the exception of hen-housed 500-day egg production. The additive-maternal variance was important for most of the traits but the correlation with the additive-direct variance, when present, was negative. There was some evidence suggesting the presence of dominance-direct variance for body weights. The presence of additive-maternal and dominance-direct variances could account for the higher heritability estimates obtained from the dam component of variance.