A man takes his Rottweiler to the vet.

"My dogs crosseyed," the man says. "Is there anything you can do for him?"

"Well," says the vet, "lets have a look at him."

So he picks up the dog and examines his eyes and ears and then checks his teeth. Finally, he says, "I'm going to have to put him down."

"What?" The man was astonished. "Why because he's cross-eyed?"

"No," said the vet, "because he's really heavy!"