Veterinary Medicine and Science, cilt.11, sa.4, 2025 (SCI-Expanded, Scopus)
Background: In recent years, research has increasingly focused on the role of light exposure in stimulating embryonic development of broilers, particularly regarding how different lighting conditions during incubation may affect growth and performance outcomes. Objectives: This research examined the effects of continuous green LED lighting (560 nm, 15 lux) throughout incubation on embryo growth, hatching performance, post-hatch growth, intestinal morphology, and carcass traits. Methods: In this study, 600 Ross-308 hatching eggs were divided into two groups: a control group incubated in darkness and a group exposed to continuous green LED light (560 nm, 15 lux) throughout incubation. Results: Results showed no significant differences in embryo weight, length, or yolk sac usage between groups at day 19 (p > 0.05). Green LED lighting reduced relative heart weight (p < 0.01) and chick weight at hatch (p < 0.05) while significantly shortening incubation time (p < 0.001). Embryonic mortality and hatchability were not affected (p > 0.05). By day 42, broilers incubated under green LED light exhibited lower body weight and cumulative weight gain (p < 0.05), though feed conversion ratios remained similar across groups (p > 0.05). Carcass analysis revealed no significant differences in yield, but relative liver weight was higher in the green LED group (p < 0.01). Subtle changes in intestinal morphology, particularly in the jejunum, were observed with age. Conclusion: While green LED lighting did not affect hatching performance, it negatively impacted body weight, heart weight, and liver development.