I have 20-30 hens. one day i noticed bugs. i didn't really know what to do, and didn't think of googling. someone told me to dust them with 7's powder. it helped but i never got rid of the bugs. then i noticed their leg scales were raising and some, got these hard white crusty thing. i was told to use Vaseline. it kind of worked. i actually had 1 hen loose her2 back toes because of lost circulation. after the hen lost those toes and my favorite hen is getting those white rock things i wanted to do something. i don't care what i use. i just want these bugs gone! after i hold one i feel like the bugs are all over me. anyway, what can i use to kill these bugs including internal parasites? i have read ivermectin it needs to be something that is not very expensive, something i can get at the feed store, and not have to dose very often. first what? how much? how often? how and where do i administer it at? i don't mind injection any other tips would be great! thx. most of my chickens are golden sex- links. i also have a couple americonas sp? 2 austrlorps and a road island red. the golden sex=links are very boney, and have never weighed that much. i can add more detail but i am in a hurry, thanks!!!