Our babies are about 9 months old and we are headed into winter (central Illinois). One of the girls started looking gangly and we noticed her neck and tail feathers are falling out. I have been seeing them on the coop floor, but assume that was normal. We have checked for lice and mites. We don't see any. I regularly DE their areas...and have even done a food grade DE dust bath per other things we saw on the net. I admit we have been letting them have more treats (USA brand meal worms and some scratch) than they probably should have. Their normal food is organic non GMO pellets and we get them a seed feed for layer organic mix that we put together. We put calcium in their food as well. I keep their water clean and have them on buckets with horizontal nipples they peck for water. She appears to otherwise act normal. The last two days I've been adding yogurt and taking up the other treats. This morning I noticed one of the other girls dropping some too. Egg production is way down - but winter is here and it is dark more. While we've had a mild start into winter I'm very concerned about her ability to keep warm without enough fluff. What have we missed here? We've combed over and over other posts and can't seem to find a direction we need to go. As of now, she has no bald spots showing...just goofy feather spots. The feathers appear to be both breaking off at the stem and pulling/falling out. She is losing both the fluffy down and standard outer feathers. Vent looks good - her skin is a pale white/yellow - there is no pink irritation. Her comb also has a bit of a white/dry looking. We put some vaseline on that and it seemed to red it back up pretty well. Just don't know what to do...we did lose one out of the blue a few weeks ago...no warning signs, just found her dead on the coop floor in the morning. She was not losing feathers prior to.