I noticed about a week ago that two of my 4 hens had lice on them. The other 2 seem to be fine, and it seems that it may be only affecting my barred rocks. So I treated them exactly a week ago, and it's getting worse! One hen has lost a good sq inch patch around her vent and even more feathers than before have eggs around the base of them. The other hen who had no eggs on her before now has way more, and it looks like more bugs too! I used this powder called "Permethrin Insectrin Dust PROzap" It is supposed to treat both lice and mites even though I'm pretty sure they don't have mites. I don't know what to do since it isn't going away, and a few days ago I got 2 new chickens a Barred Rock 9 month old hen, and a 2 month old Buff Orpington. I've been keeping them in seperate pens, and the chick is even inside, but I'm worried. Especially about the Barred Rock as I'm pretty sure its only my BR girls that are getting it...Any help?