Ron, we'd adopted a mix dog once. He refused to stay in our backyard. It's the only dog we've ever had who refused to be part of our pack. We (including the people we adopted him from ) believed the mom had been mating with coyotes. The pup was a meant to be a pitbul. but he looked almost exactly like a short furred coyote. And nothing about him looked pitty.
It's the one and only time I wasn't able to "reach" an animal. It was very odd.