GROANER

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?"
"Well," said the vet "let's have a look at him".
He picks the dog up by the ears and has a good look at his 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.