I'm not 100% sure, but it does sound like Demodex (not sure if this is the correct name) Mange. From what I understand, this type of mange is genetic, and is usually brought on by stress such as a heat cycle or pregnancy. I've not had to deal with this, so when Lisa and/or Deb to chime in here b/c they have more experience/knowledge in this area. I'll see if I can find some sticky threads pertaining to the subject at hand to help you out in the mean time and post them here.
You may want to start here, click on the link for the vet manual and try searching around in there. It is a free site, and there's no membership required. This may help you to find out some answers until Lisa or Deb can offer you any guidance. Sorry I'm not much help. Also, I believe Trevor (Nismo) might be able to help since he's a vet tech. Best of luck to you and please keep us posted. I will be keeping an eye on this thread to see what you find out. I hope that I've been of some help to you.