Sexual Maturity and Subsequent Laying Performance of Fowls Under Normal Photoperoids—A Review 1950–1975

SummaryThis review deals only with the relationship between sexual maturity induced by lighting and subsequent performance of the pullets. A total of 38 reports were examined in an attempt to summarize and arrive at a quantitative estimate of the way in which maturity of the pullets alters their egg output, feed intake, feed conversion and mortality rates during the first laying year.Two equations were employed to correct all reported measures of maturity to age at 50% production. Egg output and feed conversion rates were found to depend upon a curvilinear function of maturity, with the highest egg output and the best conversion rate obtained from middle maturing birds. Differences between stocks in their responses maturity were also evident in the sense that each stock showed different optimum maturity age.