One day old pullets of Indi~ RIR breed were reared under LD 12:12 (NLD) throughout, or under a step down photic schedule of LD 18:6 (long photoperiod; LP; from day 1 to day 90) followed by LD 12:12. The effect of these photoperiodic schedules on physical features and biochemical composition of eggs has been assessed. The LP hens laid marginally heavier eggs compared to the NLD hens. The eggs of LP hens showed higher weights of yolk and albumen and a lower yolk: albumen ratio. On a temporal scale, the percentage water content of yolk and solid content of albumen showed a reverse trend between the NLD and LP eggs. The total protein and total cholesterol contents were significantly increased in both yolk and albumen of LP eggs while the carbohydrate and total lipid contents decreased in yolk and albumen respectively. A compari son of calorific value shows significantly greater energy content (13.4%) in LP eggs. Overall, the present evaluations provide hitherto unreported evidence of a step down photoperiodic schedule on the structure and composition of eggs and their nutritional status.
