I have 11 hens in my flock, no rooster. About half of them looked like they were molting for a while, but its been about 3 months, and some of their backs still look like a corn cob that has been picked clean. I don't think they have mites or lice, and havent noticed them picking excessively. They do seem to be laying less. 3-5 eggs per day for 11 chickens. I feed them layer ration and throw out black oil sunflower seeds for them to pick at during the day. Their coop is about 8x8x4 feet and they run outside every day in a 12x12 foot run. Which admittedly has been pecked down to dirt. Any suggestions on what this can be? They don't seem unhappy, but look pretty pathetic.