We have six hens. Two three-year-old highline browns, (Which is a commercial laying breed we got from an organic egg farm nearby), a five-year old commercial breed who is so old she is blind, a buff orpington, an Easter egger and a Partridge rock. Out of these six, there should be three who are laying right now--we don't expect the very, very old blind hen to lay,the EE has sour crop, and one of the highlines is molting. But despite the fact that we use artificial lighting in the coop, only one hen is laying--the very old, blind hen, and only very occasionally. The orp, the other highline, and the rock should all be laying right now. I've done all the normal things--checked for eggs elsewhere, have a light in the coop, ect. I have kept chickens for five years, and I am doing this winter exactly what I have been doing the past five years, and got at least two eggs a day. The only differences are different chickens and small changes to the coop--insulation, a new waterer, and wood shavings instead of straw bedding. What is going wrong here? I don't expect five eggs a day, all we really need is two or three, but why are perfectly healthy hens not laying? Thanks, Earlybird.