Intermittent Light and Light Intensity Effects on Broilers in Light-Proof Pens ,

Five experiments were conducted in light-proof pens to compare various intermittent lighting programs with continuous light and with two light intensities on broilers. In general, growth was satisfactory only if the lights-off period did not exceed 2 hours and the lights-on period apgroached that of the lights-off period in length. A program with a repeating cycle of lights-on for 1 hour followed by lights-off for 2 hours, when initiated at one day of age, gave equal growth to continuous light; feed conversion from the intermittent program was superior in all 3 trials; however, the difference was significant in only 1 trial. Performance with continuous light of 2–3 lux intensity was as good as with 6–15 lux intensity. The best overall performance in two trials was obtained with 2–3 lux of light on continuously, plus 6–15 lux cycling on 1 hour and off 2 hours. Males and females did not differ in their response to any of the lighting programs, as measured by 8-week body weight. Mortality was not affected by any lighting program.