Photoperiodic Response of Chickens

Effect of Lighting Systems in the Grower and Adult Periods Upon the Over-All Performance of White Leghorns

“…When the pullets were given light restriction in the grower period, and intermittent system in the adult period, egg production was significantly lower than for controls (Wilson et al, 1960). However, Davis et al (1964) stated no differences on all light-dark cycles with respect to rate of lay.…”

The Effect of Photoperiodism and Rearing Period Feed Restriction on the Performance of Five Leghorn Strains

“…The experimental procedures used by different workers in the study of photoperiodism have varied widely and results tend to be somewhat contradictory. Biellier and Ostmann (1960), and more recently, Smith and Noles (1963), Davis et al (1964) and Lillie and Denton (1965) have reviewed the literature on the effects of different photoperiods on the performance of egg production stock. A number of reports indicate that performance was improved for some traits when an increasing laying period day-length is coupled with either a constant 6-to 8-hour rearing period day-length or a rearing period with a day-length which is shortened, by equal weekly decrements, from day-old to housing age.…”

Effect of Ahemeral Light-Dark Cycles on Production and Egg Quality of Laying Hens

“…Research using a light-dark cycle (LDC) shorter than 24 hr has produced conflicting results. Woodard et al (1962), Marks and Lucas (1963), and Davis et al (1964) employed LDC of 16, 18, or 20 hr. They found that egg production was lower for these LDC than a 24-hr LDC.…”