Hello, I was hoping to get some advice from some of you chicken experts out there! i've got a mixture of young chickens and hens that have just come into laying. They all free range and they are all in the same large coop and run now, however, the younger ones are missing feathers mostly in their neck, tummy, Bum, and back areas. Prior to combining all the chickens together, I was already noticing the littler ones starting to look like they were missing feathers just as soon as they're real feathers came in. When they were big enough to let loose with the bigger chickens, the problem continued but none of my bigger chickens have any bald spots like these young ones. I had thought that perhaps the enclosure was becoming too small for the younger ones and that maybe they were picking on each other causing the balding look and that once they had more room to run around their feathers would grow back- but that is not the case. I am including some pictures of what it looks like. If anyone knows what this could be I would greatly appreciate it!