I use diatomaceous earth food grade even for 1 mite. Put it on the floor trays,, in the dust baths and see 1 give her a massage getting the diatomaceous down to the skin. Check her in 2 days and the next if any diatomaceous earth again.
Well I don't really know. So the second vet said her skin could not grow follicles and s would not be able to grow skin. She is soaking daily and put on silver sulfadizine.
I use diatomaceous earth food grade only. It has helped. Every one gets fluffy bottom with it if I see any on anybody.
When I started raising hens I couldn't believe how fast .it's would take down a girl.
I'm sad I didn't take their care more seriously.