Hens with feather lost under neck

[kellycoop]

Could someone help me please, I have a few hens shaking their heads and lost of feathers under neck. I have dusted the coop and clean it all the time. Some have very poopy behinds also. If it is lice or mites why can't I see them and how do I get rid of them!! Thanks

 

[Judy]

Dusted with what? Have you looked for them at night with a light? Not all of them stay on the bird during the day. It might help us if you answer the questions in the sticky for this forum.