I am of the opinion, that any dog,regardless of breed, can turn,vicious at the drop of a hat,...its the nature of the animal,it can be the most mild good tempered beast that you ever did own....but they can and often do turn vicious for no apparent reason....take our dog for instance,..a more good tempered dog you could ever think of owning, we have had here for 6 years,and she is a very couthy animal,...but a few months ago, we saw a side of her, that shocked Avril and I,....went we got her she was 11 months old,..we brought her home into a household that had 2 cats,...from the outset she got on reasonably well with the cats, what i mean by that is, she gave them a wide berth,..and there were never any major confrontations....t hat is ..until a few weeks ago,..when for no apparent reason,she attacked our eldest cat...Poppy,..who is a very old lady...17years old,..she, Bess, grabbed Poppy in an instant and tossed her into the air,..before a very startled Avril and I,...fortuntately,we were there and were able to rescue Poppy, and no lasting damage has been done...but we were, and still are at a loss, as to why the dog attacked Poppy....suffice to say, we do not leave them together when we are not in....