This study was conducted to evaluate the effect of a 12 hours light, 12 hours dark (12L:12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hatch performance and the hatch process. In the light-stimulated group, the monochromatic light was provided by a total of 204 green LEDs (522nm) mounted in a frame which was placed above the eggs to give even spread of illumination. The control group was incubated in complete darkness. Four batches of eggs (n=300 per group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown-rump length compared of embryos incubated under green light were significantly longer than those incubated in the dark condition at day10and day 12,... |