Effects of monochromatic green light stimulation during embryogenesis on hatching and post-hatch performance of four strains of layer breeder

Abstract Providing green light during incubation has been shown to accelerate the embryo development and shorten the hatching time in broilers. Few studies have concentrated on the exact effects on layer breeders in the aspects of hatching and post-hatch performance. In this study, four strains of layer breeder eggs, namely White Leghorn (WL), Rhode Island Red (RIR), Columbia Rock (CR), and Barred Rock (BR) were used to assess the effects of monochromatic green light during embryogenesis on hatching performance, chick quality, and pubertal growth. Each strain of 600 eggs were incubated under photoperiods of either 12 h of light and 12 h of darkness (12L:12D, light group) or 0 h of light and 24 h of darkness (0L:24D, dark group) for 18 d, with two replicates for each treatment. The results showed hatch time, time reaching 90% hatch, and average hatch time were significantly shorter among the four strains in the light group (P 0.05). There was no significant difference in hatchability of fertile eggs, chick weight/egg weight, or chick quality among the four-strain eggs between the light group and dark group (P > 0.05). There was no difference (P > 0.05) in post-hatch BW between different light treatments of the three strains (WL, CR, and BR), while the BW of RIR was higher in light group than that of the dark group at 8-12 wk of age (P