Effect of smooth switching the light on/off under intermittent LED lighting on the productivity of laying hens

The influence of smooth switching the light on/off on the productivity and viability of laying hens of the SP-789 cross was studied. In the experiments, three identical groups of 120-day-old birds were formed. In the first preliminary experiment, poultry was raised up to 410 days of age, in the second main experiment it was raised up to 350 days of age. All birds were kept in cage batteries under intermittent LED lighting. The light was turned on at 2-3 am, 8-12 am, and 2-5 pm. In both experiments, lights were switched on and off instantaneously in the control group. In the first preliminary experiment, the sunrise and sunset imitations took place each time the light was switched on and off, and lasted 3 minutes in the experimental group No.1 and 6 minutes in the experimental group No. 2. In the second main experiment, in the experimental group No.1 the mode of imitation of sunrise and sunset was similar to that of the experimental group No. 1 of the first preliminary experiment. In the experimental group No. 2, sunrise was simulated only during the first light turn on, and sunset was simulated during the last light turn off (3 min). The best results were obtained in the group with smooth switching the light on at the beginning of the first photoperiod and smooth switching the light off at the end of the last photoperiod (for 3 min). As compared with control, this group showed an increased livestock livability (91.7%) by 1.9%, egg production (171.6 eggs) and yield of egg weight (9.81 kg) per initial and average laying hen by 7.3% and 6.5%. Feed efficiency per 10 eggs (1.33 kg) and 1 kg of egg weight (2.32 kg) decreased by 5.0% and 4.5% respectively.