Interesting. We have a show up special that's been here 6&1/2 years. He just showed up, ate all the cat food and hasn't left so he must like the joint. Has similar body structure to yours with Aussie Cattle Dog (Healer) colors but vet thinks some sort of Terrier on the other side of the coin. Wasn't very old on arrival and no collar, tags, or chip to be found. Big man when the cattle are on the opposite side of the fence but when you have an open gate he's as helpful as a cat. Herding instincts missed the genetic boat.....