In the episode "Homeward Hound", Scooby-Doo and the six puppies are accidentally thrown into a river. While they're going down the river, Scooby Doo really tries his best to protect the puppies who are flying around everywhere, before they are saved from getting shredded to pieces in a timber mill.
In the same episode, Scooby goes Papa Wolf when the "cat-creature" menaces the puppies and their mother. With a snarl, he actually leaps onto said monster and pushes it onto a serving cart, then crashes the cart to immobilize the monster. Don't threaten puppies in front of Scooby-Doo.