mates dog had been steady with ferrets, then one day when bunies were bolting the ferret had come up and the dog picked him up and there was a lot of squealing . The dog got a sharp rap across the snout! and a LEAVE!!! from that moment on he has shown no attention to ferrets, and this was the only instance. we put it down to a young dog being excited with bunnies bolting all over the shop.
Point I am making is if your dog has not been introduced at an early stage , you will need to introduce him/her very carefully under controlled conditions, perhaps in the house where room is limited .