Kansas City, Mo. ? The cameras were rolling as Willy the wiener dog stopped his trick for a blissful restroom break center stage.

Nearby, Quarter Pounder, a 650-pound miniature bull from Olathe, Kan., decided he had waited long enough for his shot at stardom. With a flick of one horn, he convinced his master — and any other humans standing too close — that it was time to leave. Now.

Then there was Aspen the German shepherd, who, perfectly on cue, raised his 110-pound self upright to croon a howling canine karaoke to a recording of country singer George Strait. He was only slightly out of tune.

Some tricks were planned. Others were, well, unexpected performance pieces.

From morning to midafternoon Saturday at Broome Chevrolet, at least 45 acts auditioned for a shot at appearing on the Stupid Pet Tricks or Stupid Human Tricks segments on CBS’ “Late Show with David Letterman.”

Each artist tried to entertain the crowd the way he or she had done so many times before, recreating those magical moments spawned in homes across the Kansas City area.

Louis Laugesen, 64, of Kansas City, stood fearlessly in front of the cameras. His electronic piano played a prerecorded meringue rhythm while he flicked his hands in a little dance, palms up, then palms down.

“I usually do this with my cat,” Laugesen said afterward. “But I couldn’t catch it today, so I improvised. My cat really makes this better.”

Cassidy Cooper, 10, of Tonganoxie, Kan., frightened a few spectators when Sylvester, her 2-year-old cockatiel, walked inside her mouth to get a cracker wedged between her back molars. For a second, all you could see was half of the bird’s tiny body and a flange of gray feathers arcing in a swoop out of the girl’s smiling lips.

Sylvester usually climbs all the way in Cassidy’s mouth, but Cassidy’s mother asked her daughter to refrain from “going all the way” because Sylvester sometimes pecks on Cassidy’s uvula, that thing that hangs down the back of the throat.