You do not say how your ferrets are being treated, with what
medication. James Fox's Biology and Diseases of the Ferret 2nd E. p.387
suggest dipping in a 0.0125 Amitraz suspension several times over some
lengthy time with the same medication as ear drops and extra strength
tail dips, followed by more higher strength dips for whole body
again.with eventual complete cure. I will give the full treatment
schedule if you need more details.

Tony (not a vet), Sugar and Suki.
In memory of Sally and  Sue.

[Posted in FML 5751]