Get a pit bull. They are smart, faithful, funny, strong, and they will take out those gophers if you let them. They get a bad rap for being mean or contrary--for decades they were the standard family dog. You simply have to understand that you are the alpha dog--if you understand it, your dog (of whatever breed) will understand it. You may need to get a young dog of whatever breed to raise it around the cats. My dogs live outside and the cats live inside because we haven't managed to convince the dogs to leave the cats alone. (My second dog is a blue heeler/catahoula mix. A herder, a sweetheart, and an annoyingly hyper pooch).

SRS