Photoperiodism as a Factor in Feeding Rhythms of Broiler Chickens

Abstract

BROILERS exposed to continuous light at a single intensity during the growing period are heavier than those exposed to either varying intensities or intermittent light and dark periods (e.g. Moore, 1957; Shutze et al., 1960; Krueger et al, 1963; Beane et al., 1962, 1965). Observations indicate that under continuous illumination growth is more rapid at low than at higher intensities (Skoglund and Palmer, 1961; Cherry and Barwick, 1962; Beane et al, 1965). The diurnal feeding patterns of broilers have been studied by Siegel and Guhl (1956) and Siegel et al. (1962). They found that the percentage of birds feeding was highest at the beginning and at the end of the daily light period suggesting that the birds have become conditioned to the dark periods. The experiment reported there was designed to determine feeding rhythms, growth, feed efficiency, and endocrine responses of broilers maintained under several light regimes. EXPERIMENTAL PROCEDURE Four . . .