Just to share my costly experience about lighting effect to quail. This happened to me about a month ago when I unintentionally instruct my worker not to turn on the light at night. The natural light is from 7am to7pm more or less, may be maximum at 13hour/day. My egg production went down drastically from 600-700eggs to only 10-20 eggs/day in 2 weeks time only. When I realize the reduction, its already too late and my quail started to molt, the feathers everywhere, the roos didn't crow at all, very quite week. Luckily today they getting better, now I am getting almost 600eggs/day back since last 4 days. What I notice during molting period, my quail didn't like their normal food, they throw the food away, pecking the food but didn't eat it.