A man took his Rottweiler to the vet and said to him, "My dog's cross-eyed. Is there anything you can do for him?" "Let's have a look at him." So the vet picks the dog up and has a good look at its eyes. "Well," says the vet, "I'm going to have to put him down." "What?" shouted the man in fright. "Just because he's cross-eyed?" says the man. "No, because he's heavy," says the vet.