We have a rat terrier, so you can guess where this post is going. He's a retired therapy dog, so his training and background make him a pretty gentile and loving dog. He loves our other pets too, his best friend is my daughter's cat. As far as being a terrier, he has a lot of that high energy personality common to terriers, but rat terriers have a kind of "off switch" that makes it easy to transition them into a calm and relaxed state. (All in all, IMO a great breed if you can make the commitment to training and socialization starting from a young age and maintain it throughout their lives). So the cats like to catch wood rats and bring them alive into the house where they get released. My wife and daughter, of course just love that. I am thus the appointed rat hunter. Fortunately, I have a deadly weapon to assist. Turns out Mooshu has another switch, one that requires no training. I just say, "Mooshu, let's get that rat" and he turns into a deadly predator. The rat could be anywhere in the house, but he'll find it for me and go into an alert posture near whatever furniture or appliance the vermin is hiding under. Last night it was the kitchen stove. I move it away from the wall, and Mooshu has that rat in his mouth quicker than the eye can follow. A couple of flicks of his head back and forth and the rat's back is broken. I tell him to drop it and he puts it at my feet (usually still breathing so I finish the job) and I dispose of it. Once it is over, that is one happy dog. I mean dog's live to please their owners, but when they get to do it in the capacity of their breeding? They go to a whole new level. The cats used to be able to catch rats a few times a week, but lately it has been months in between catches. I figure we are doing the neighborhood a public service.