Exogenous Regulation of Oviposition in Chicken

Abstract

THE circadian rhythm of oviposition in chickens is well established, but the exogenous stimuli which influence the release of humoral factors involved in egg production are not. This study considers the influence of sound, feeding time, and light on time of egg-laying by chickens. In his review on diurnal rhythms, Aschoff (1963) has defined the “Zeitgebers” as the periodic factors of the environment by which free-running circadian oscillations can be synchronized. Shifting laying hens from 14 hours of light per day to 24 hours continuous light results in eggs being laid at a uniform rate throughout the 24 hours (Warren and Scott, 1936). Shifting the time of lighting alters the time of oviposition, according to Bastian and Zarrow (1955), Lanson and Sturkie (1958), and Biellier and Ostmann (1960). The use of 1-minute periods of intermittent light resulted in eggs being laid near the light period (Wilson and Abplanalp, 1956). A…