Genetic variation in the incidence of pipped eggs in turkeys selected for low and high semen ejaculate volume.

Genetic variation in embryonic mortality, expressed as embryos that pip their eggshell but do not hatch, was investigated in turkeys selected for low and high semen ejaculate volume (SEV). Through five generations (Generations 10 to 14, inclusive) mean heritability estimates for pipped eggs were .21 and .08 in the low- and high-SEV lines, respectively. Estimates of sire, dam, and within-hatch components of variance suggest greater environmental and maternal effects than genetic influences on the incidence of pipped eggs in turkeys.