A young father bought a Doberman Pincher puppy as a family pet. The puppy was loving and playful, a good companion. When the dog reached a year and a half he became aggressive, nipping at the children and the neighbors. The veterinarian tells the dog's owner that the dog has reached puberty and the solution is castration. The owner makes an appointment for the following Tuesday for the procedure. That Saturday the man is walking the dog down the street near his apartment when the dog spots a homeless man going through a trashcan down the alley. The dog becomes agitated, breaks loose from his owner, races down the alley and attacks the homeless man. The owner rushs down, pulls the dog off the homeless man who has been bitten several time on the arm and says:
"I'm terribly sorry, we're going to have him castrated on Tuesday."
The homeless man replies: "I don't think that's the problem, I could tell from down the alley he didn't want to screw me."