Disease?

[CKoz]

My Rhode Island Red has lost her feathers (see picture). They have been gone for over two months with no sign of regrowing. She is one year old. She has access to a dust bath with DE for 3 weeks. She seems to be acting normal. Today I noticed my other Rhode Island Red has some thinning of her feathers around her neck. Same age and also seems to be acting normal. Additionally, I have a golden comet who has lost her butt feathers and a couple of tail feathers. She had a few pin feathers grow back but still has some bare skin. She lost her feathers about the same time as my first Rhode Island Red. I have also sprinkled DE in the coop but not the run because it keeps getting wet with all of the rain we have been getting.

 

[sourland]

Some bird or birds in the flock are feather pecking/plucking them. If there's a bird in perfect feather, that's the culprit.

 

[CKoz]

I have 7 other chickens in full feathers. Any suggestions?

 

[nuthatched]

What's their diet? Have you checked for mites or lice? DE does nothing for either and isn't good for your birds or you.