A man takes his dog to the vet, because the dog has been feeling poorly of late. In the surgery the vet examines the dog, taking temperature, feeling the dogs abdomen and smelling his breath. The vet steps back and shakes his head ruefully.
"I'm sorry" he says "Your dog has kidney failure. He has two days left to live."
The man is appalled at this terrible diagnosis, and demands a second opinion. "Well, okay" says the vet, and picks up the phone. He mutters into the receiver for a few seconds and then puts the phone down. A minute later a cat comes into the surgery.
The cat looks the dog over for a short while, and then turns the vet and says "Kidney failure?"
"That's what I thought" says the vet.
"Yep. I'd say he has two days, maybe three." and the cat walks out.
The man reacts angrily to this. "What the hell was that? I'm not taking a cat's opinion. Get someone else."
The vet replies "Okay" and picks up the telephone again. After a short conversation, and a little wait, a Labrador walks into the surgery. The Labrador examines the other dog briefly and then announces "Kidney failure, by the look of it. Not much more than two days left in the old boy."
"I concur" says the vet and the Labrador leaves the room.
The man has had enough and decides to leave "Right. I'm leaving."
"That will be 450 dollars" says the vet.
"What! That's a fortune! What the hell do you think you're playing at!"
"Well if it had just been me" says the vet "it wouldn't be that much, but after the cat scan and the lab report..."