Heritability Studies of Egg Production in the Domestic Fowl

Abstract

WHETHER genetic progress is being made has been a topic of increasing concern among poultry breeders. It may be worthwhile to consider some of the possible reasons why this important question should arise in the minds of these breeders. (1) Perhaps an over optimism on the part of the breeders could be an answer. (2) Most demonstration projects have been primarily concerned with only one trait. Most commercial breeders find it necessary to consider several traits, which fact greatly reduces the chance for progress in any one trait. (3) Has the environment been getting worse all the time, thus masking any genetic progress made. As yet, outside of an experiment just beginning (Gowe, 1952), efforts to measure environmental trends have not been attempted in poultry breeding. (4) One might hypothesize that the selection programs utilized to date have used up all or practically all of the additive genetic variance, leaving …