Hi mate,
From my own experience, I have a paterdale terrier, 6yrs, brought up wih ferrets about, a great fox dog, rats etc too. She will happily work all day with ferrets, even ignoring them at the mouth of holes, All sounds good right?
Well, she managed to kill 9 ferrets , this was two jills and their litters, the patt was loose in the garden and nobody there to see anything. She'll go through a cage to get to them.
So you'll have to see how yours goes, Best of luck.
PS ferrets now kept in a dog proof enclosure