What's wrong with my chicks feathers?

[dboranch]

I have 4 individual pens of chicks inside my garage at various stages of growth until they are fully feathered to go outside. I have a sportsman incubator and hatch out hundreds of chicks each year but I have something unusual going on at the moment. It is only in one pen and the other pens seem fine. It has been going on for a couple of weeks now. Can anyone tell me what's going on with the feathers of these chicks? They are maybe 5 to 7 weeks old I have given them a thorough check for cooties and have found none. They were due to go outside in my grow pen but I am afraid to put them in with the others in case it contagious or something. Any help would be greatly appreciated. Thanks so much.

 

[Poultry parent]

it looks kinda like other the feathers are being pulled out, and pecked at