They're all making small talk with each other (they all have big dogs, etc), when one looks to the other and says, "So what are you here for?"
"Well," the girl with the black Lab says, "My dog's a compulsive chewer--he's chewed up EVERYTHING in my house. He got hold of my Manolo Blahniks, and well, that's just the last straw--I brought him in for that new dog-Prozac."
"Aaah," the girl with the yellow Lab says. "My dog's in the same boat, but he's a compulsive whizzer--he marks his territory EVERYWHERE!! I lost it when he peed on my new laptop, he's here for the same thing."
The women look at the girl with the German Shepherd, who's sitting there snickering to herself. "So what about you?"
"Heh, my dog's a compulsive humper," the woman with the German Shepherd says. "My dog will hump anything--pillows, table legs, small children..."
"Oh my god," one of the other women says. "What made you bring him in?"
"I was just out of the shower the other day, and I was bent over the commode, one foot hiked up, painting my toenails," the woman patted her German Shepherd, "and Alex came in, mounted up, and just started whaling away!"
The other two women were FLABBERGASTED! "Oh God! So you're here for that new dog-Prozac too??"
"Nah, he's just here to get his nails trimmed."