Second Year Egg Production in Relation to First Year Egg Production in the Domestic Fowl

Abstract

Studies on the inheritance of egg production have been in relation to the first year production almost entirely, in which respect first year production has been considered to be composed of four definite cycles, the winter cycle from November to February inclusive, the spring cycle from March to May inclusive, the summer cycle from June to August inclusive, and the fall cycle including September and October. That the first year production should be divided into four such arbitrary periods seems very questionable in the light of recent studies. Brody (1921), from an analysis of the first year records of production of 4,210 Barred Plymouth Rocks at the Maine Agricultural Experiment Station and 1,000 White Leghorns in the Storrs egg laying contests, determined that egg production is of the same general order as the growth of organisms. The curve constructed by Brody, shown in Fig. 1, shows no tendency of indicating .