I have 5 hens who are 20 months old, 1 hen who is about 2 yrs old, 3 pullets/hens that are 8-1/2 months old. My 6 older hens were laying just fine until about the beginning of October - then they molted. They now have all their feathers in but still have not started to lay again. My other 3 younger girls - 1 started laying in late Sept but stopped at the end of October and the other 2 - I got 2 eggs from at the end of October then nothing. I have not had any eggs since the end of October! What is going on??? Last year with my first 5 hens I had eggs starting in early November and they laid all through winter. I feed them Purina Layena, oyster shell is available. They have a light on a timer to give them additional light (it is a cool florescent light does not emit any heat). They look healthy and act healthy. Help!!!!!