Talking 'single handed'. Theres a lot of evidence of many different types of dogs taking wolves. Which is quite a feat, but as a wolverine will see off a wolf, say, from a kill, then I would guess they are a much tougher beasty altogether! Leopards were and still are hunted with dogs, but a pack of them, often ridgebacks, or hounds, and crosses. Which bring the leopard to bay, to be then shot... ive never heard of a dog to take one single handed.