have a dog here, that was raised round chicken sheep and cats, was great off lead round stock, was walking her one day and something in her went off and she grabbed a sheep by the ass and hung on, eventually broke her off and despite some strict discipline she has proved she cannot be trusted at all off lead anymore around sheep,cats chickens or white dogs, if she wasnt looking so promising I would probably cull her, cos to be honest shes looking like a liability. Now to all the experts, is that because she wasnt raised or brought on properly round stock? I dont think so.