Integration of classical and molecular approaches of genetic selection: egg production.

Poultry breeding has demonstrated success from the use of a complex mixture of assessment tools. New proposals are regularly sought out and tested for their ability to translate data into information that enhances genetic gain from selection. Details long hidden from view are already being uncovered by molecular genetics, calling for great skill and discipline to discern and harness their real potential. Some aspects of egg production grudgingly may yield to the influence of new associations suggested from molecular work. In particular, diverse environments call for the kind of genetic variation found only under expensive multiple-location testing, longer flock production life calls for better early predictors, and new egg products call for novel measures of egg component value. In the final analysis, selection on a mix of phenotypic and molecular data is an essential step in evaluating its worth for improving a physiologically complex trait like egg production.