i live in massachusetts, so it's been pretty cold. i have 8 ee hens, that seem to be healthy and happy, we get an average of 6 eggs per day, they are in a house we sized for 16 hens, and they eat like crazy: layer crumbles, greens and corn. yesterday one hen had a bald spot on her back today several more do! I don't see any mites, and they're still eating and laying. we put corn and greens around outside to encourge them to come out and scratch around so they don't get bored anyone have any ideas? they were hatched & gotten from Ideal last july... thanks in advance, i'm a little freaked out!