This might be another case of a vet refusing to diagnose mites because they didn't show up on the skin scrape. My vet won't prescribe ivermectin and I'm scared to try and dilute and dose it myself for fear I'll overdose my pig.
I've separated the pigs and took pictures of Bean this morning after applying his medication. In this journal entry you will find pictures - since hopefully if you are reading this you know more about pigs and mites than I do, please let me know what you think.
http://twoswimy.livejournal.com/456527.html