A Study of the Effect of Restricted Lighting on January Hatched Pullets

THIS study was conducted primarily to determine whether the early maturity and high rate of egg production normally observed with January hatched pullets could be regulated and controlled by restricting the number of hours of exposure to light as the pullets approached the age of sexual maturity. That this seemed logical and possible was evidenced by studies involving hours of light and sexual maturity made by Callenbach, Nicholas and Murphy (1944), and indicated by Jeffrey and Piatt (1941) in their studies on out-of-season hatching, as well as in reports of a similar nature by Moore and Mehrhof (1946) and Skoglund and Tomhave (1948). White Leghorn pullets hatched January 28, 1953, were divided into 2 groups on April 28 when 13 weeks old. One group of 67 birds was kept confined to a pen 10×20 feet in size (3 sq. ft. per bird) and maintained under normal day-light hours. A second …