Hello! I'm hoping all you more experienced people can help me out here! I have 22 chicks in a brooder. They're about 6 weeks old. 18 are mine that I hatched and 4 are chicks I purchased locally from a "breeder" who is a frequenter of BYC so will remain unnamed. Anyway, when I purchased the 4 chicks, the conditions they were living in were filthy, just abhorrent. That should have been a red flag but I purchased the chicks anyway. After quarantining them they joined the brooder with the others and all appeared well. That was about 5 1/2 weeks ago. Lately I've noticed that as the adult feathers are growing in on 3 of the 4 purchased chicks, they are practically bald along their backs and chest/breast areas. Their wing feathers are coming in nicely. My other chicks are all completely feathered out, none of them have any baldness. The 4th chick has feathered out completely and looks beautiful. I don't see any open areas, no bleeding. I thought I saw some scabbing but it's hard to catch them as they're VERY wild. (the one's I hatched and raised are quite tame). Any ideas what's causing it? They are very active and otherwise appear healthy. One last note...one of the 4 chicks that I purchased had fuzz that was all matted down, like it had something on it the day I picked them up. The "breeder" said it was just 'egg junk' from hatching. I didn't think anything of it at that point. They were 1-2 days old when I purchased them. Again, should have been a red flag. Needless to say I won't buy from this "breeder" anymore and I wish I could warn others to stay away. The bottom line is I just want to make sure my chicks are healthy. Thanks for any info and advice you may have!