The effects of different lengths of the subjective day on the productive performance in laying hens under intermittent lighting regimes
The effects of different duration of the subjective day on the productive performance in laying hens under intermittent lighting regimes with skeleton photoperiods were studied. The 14-hr subjective day (in compare to 13-, 15-, and 16-hr) increased live bodyweight in layers by 2.0-3.3%, egg production per initial and average hen by 3.3-5.2 and 3.2-5.2%, egg weight by 0.7-1.2%, egg mass output per initial and average hen by 4.5-6.7 and 3.1-4.6%; decreased feed expenses per 10 eggs and 1 kg of egg mass laid by 2.9-3.6 and 3.5-4.9%. Chemical composition and morphology of eggs were not affected by the length of the subjective day.