And as a bonus, here's a dog joke: A man takes his Labrador to the vet and says, "My dog is cross-eyed. Is there anything you can do for him?"
The vet says: "Well, let's have a look," and picks up the dog to examine his eyes.
Finally the vet says, "I'm going to have to put him down."
"What? Just because he's cross-eyed?"
"No, because he's really, really heavy."