Is it lice or mites, or something else?

[Rose_coop]

I have a prarie bluebell who has a patch of feathers missing on her back, and the exposed skin looks rough (pictures attached). I initially thought it might be lice or mites, and so we checked our whole flock. I didn't see any bugs, eggs on feathers, or red vent areas. It seems to be just this one bird. Any ideas about what this could be? Could it still be pests that just haven't gotten to anyone else?

 

[ChickenCanoe]

Do you have a rooster?

 

[Rose_coop]

We did have a silkie rooster until 2 weeks ago. We thought it was a hen, but out of nowhere it started crowing and mating. He went to a friend about 18 days ago.

 

[ChickenCanoe]

The damage to me looks a lot like the favorite hen of a rooster. Maybe she was the only one that would let him mate.
Have you dusted her/them?

 

[Rose_coop]

Dusted for mites or lice? No, we haven't. We just noticed this yesterday, and checked everyone this morning but didnt see anything in anyone else. Would you suggest treating for live or mites just in case?

 

[CarolSMargerum]

I don't think this is merely from feather picking or mating. There looks like there is a greater issue, something dermatological going on. Considering that you are not seeing any evidence of poultry lice or fowl mites, I would treat for depluming mites and maybe use a hen saddle while healing as a secondary precautionary measure.