Three dogs were sitting in the waiting room at the vet's when they struck up a conversation. The Black Labrador turned to the yellow Labrador and said, "So why are you here?"

The yellow Lab replied, "I'm a pisser. I piss on everything....the sofa, the curtains, the cat, the kids.  But the final straw was last night when I pissed in the middle of my owner's bed."

The black Lab asked, "So what’s the vet going to do?"

"Gonna cut my nuts off "came the reply from the yellow Lab. "They reckon it'll calm me down."

The Yellow Lab then turned to the Black Lab and asked "Why are you here?"

The Black Lab said, "I'm a digger. I dig under fences, dig up flowers and trees, I dig just for the hell of it.  When I'm inside, I dig up the carpets.  But I went over the line last night when I dug a great big hole in my owners' couch."

"So what are they going to do to you?" the Yellow Lab inquired.

"Looks like I'm losing my nuts too," the dejected Black Lab said.

The Black Lab then turned to the Great Dane and asked, "Why are you here?"

"I'm a humper,"  said the Great Dane. "I'll hump anything. I'll hump the cat, a pillow, the table, fence posts, whatever.  I want to hump everything I see.  Yesterday my owner had just got out of the shower and was bending down to dry her toes, and I just couldn't help myself.  I hopped on her back and started hammering away."

The Black and the Yellow Labs exchanged a sad glance and said, "So, it's nuts off for you too, huh?

The Great Dane said, "No, apparently I'm here to get my nails clipped!"