Cross-Eyed Rottweiler

A man took his Rottweiler to the vet and said to him, "My dog's cross-eyed. Is there anything you can do for it?"

"Well," said the vet, "let's have a look at him." The vet picks the dog up by the ears and has a good look at its eyes.

"Well," says the vet, "I'm going to have to put him down."

"Just because he's cross-eyed?" says the man.

"No, because he's heavy," says the vet.