HERSHEY, Pennsylvania — On a stage in a conference hall in central Pennsylvania, at least 14,000 years after humans domesticated wolves into dogs, Milena Kon was turning a dog into a gazelle. And an elephant. And a lion. And a giraffe.

This evolution, taking place during one of the nation’s highest-profile dog grooming competitions, involved strategically dying the white fur of a poodle named Soleil to the hues of African animals, sculpting her hair into horns and tusks, airbrushing elephant toenails to her back legs and attaching googly eyes to her rear end.

“Anything artistic is what I’m drawn to,” Kon, a graphic designer-turned-dog groomer from New Jersey, said before the event. “And I love dogs. They’re my passion. They’re my weakness.”

This “creative grooming” contest was the crowning event of the nation’s largest dog-grooming trade show, Groom Expo. But the action was just as buzzy beyond the stage, in hundreds of booths selling polka-dot barrettes and bubblicious dog cologne and in dozens of seminars with titles including “Thinning Shears . . . the Wow Factor!” Amid it all, thousands of groomers were buying specialized gear, networking and commiserating about long client waiting lists in a field that these days counts all dogs — not just poodles, the traditional canine topiaries — as canvases worthy of transformation.

All had some part in a $6.5 billion pet services industry that has doubled over the past decade, fueled by the rapid rise of what marketers call the “humanization” of pets. When it comes to dogs, that has meant a migration not only from the backyard into the house, but also into the bed and the car, where they’re often treated as nicely — and expected to smell as nicely — as the rest of the family.

Groomers have responded. When the expo debuted here 30 years ago, 350 showed up. This year, nearly 5,600 came.

“The biggest factor of all is that so many people consider their dogs to be children,” said Todd Shelly, president of Barkleigh Productions, which hosts several dog-related trade shows and publishes Groomer to Groomer magazine, which would feature the creative contest’s winner on its cover. Mercedes-Benz and other prominent companies are increasingly advertising in the publication, he said, because they’ve come to view groomers as “influencers” — people who have the ears of a dog-loving nation.

And while there’s much overlap between the grooming world and the show dog world, Shelly said, more and more groomers are devoted to what is arguably the vanguard in American dogdom — the rescue dog.

“I had dogs growing up. I think we just hosed them off in the backyard,” said Corina Stammworthy, who not long ago was a biotechnology graduate student preparing for a career in research. Instead, she opened a self-service dog-bathing shop that later added grooming, and now she employs 14 people.

Her customers represent a wide socioeconomic range, she said, and their pets are anything from mutts that come in weekly to show dogs. “We’re finding more and more the line’s being blurred,” she said.

That is also happening at Groom Expo. Stammworthy was standing in a parking garage that served as a bathing area for the dogs in the expo’s various competitions, which at this moment were shelter dogs. Now in its fifth year, the rescue-only event pairs homeless dogs with groomers, who have 21/2 hours to give them makeovers that, the idea goes, will increase their chance of being adopted. Contestants are judged not just on the cuts, but also on their handling of dogs that might never have seen clippers before.

In a stainless tub next to a mound of wet towels was a bewildered chow mix named Brownie. He was being lathered by the gentle hands of Miranda Kalonarou, a groomer from the Astoria neighborhood in Queens and the winner of the rescue contest last year. She was using the provided shampoo, though it was not ideal.

“It does matter,” she said, but given the time limit, she opted against lugging her own products to the garage. “A good cut starts with a good bath. And he’s filthy.”

On stage after the bath, Kalonarou trimmed Brownie to a shinier and sleeker version, then finished him off with a bow tie. Next to her, another contestant pampered Mr. Lily, a little white dog with Yoda-like ears and the sort of misaligned underbite that could make him an Instagram star. (His groomer took second place, winning $1,500.)

Out in the exhibition area, at least a dozen booths were selling shears that all looked similar to a layperson, but which their representatives assured were not. On one side of a hallway, a salesman extolled the virtues of an “effortless” pair of scissors that “does most of the work.” On the other side, Bob Edman, a towering former machinist, stood confidently over a shiny array of his own, Aussie Dog Shears.

They are the best product for the price, he said. He goes to all the expos, and lately, he said, he’d been wowing people with his new “phenomenon,” a copper comb that he says has antibacterial properties, among other advantages. Edman said he was certain he’d sell all his stock, though he insisted money is not why he makes dog scissors.

He does it for the groomers, he said, who are “not phonies,” but are generally just good people.

Few ordinary dog owners want rainbow hues, groomers said. Even so, hundreds of people came to watch the creative grooming spectacle on the last day of the expo.

A dozen groomers were in the running. All their dogs were poodles, which is typical, said Emily Myatt, a grooming school owner who flew from her home country of Australia to judge the competition.

“You want a dog that likes to be shown off, and poodles are those types of dogs,” Myatt said. “They like to strut their stuff. They’re very prancy.”

Unlike other competitions, where all the grooming takes place during the event, creative groomers’ dogs can arrive with pre-dyed fur. Before the contest, the color-splotched pooches resemble afghans — the blankets, not the dogs.

The sculpting and finishing happens on stage. More dye is airbrushed on. Bling can be added but nothing that restricts movement, Myatt said. Hot glue guns are not allowed. Dye must be nontoxic.

The best have perfectly precise color lines, no loose hairs, and creative themes that don’t require too much effort to understand, she said.

Creative groomers insist the dogs do not mind the garish results and that they even enjoy it.

“They see the attention that they get, and that’s what I think they like,” said Kon, who owns two mobile grooming vans that she said serve many young couples who view their dogs as kids. Kon took up creative grooming four years ago, and now she owns 10 poodles.

“I have a big backyard,” she said.

In past years, Kon has done “Finding Dory” and Wonder Woman themes. This year’s African safari idea was inspired by Soleil, she said, whose petite stature reminded her of a gazelle.

“When I show people my pictures, they’re like, ‘No, that’s not a dog,’ ” Kon said. “And I’m like, ‘Yes!’ “

Other themes this year: the horror film “It”; a farm tableau complete with John Deere tractor; and two “Game of Thrones” dogs, one of whose owner explained to the audience that she was tired of waiting for a new season, “so I decided to go ahead and decorate my dog as the show.”

Kon, who’d won several contests earlier this year, didn’t place, though she came close to snagging the people’s choice award. The victor was a groomer who used her poodle’s fur to create the characters of the 1980s cartoon “The Wuzzles,” which most people, including Myatt, had not heard of. It didn’t matter: The detail was what counted.

“Go ’80s!” the winning groomer shouted, to an audience and industry planted firmly in the present.

Louie, a 2-year-old toy poodle, is groomed during the Groom Expo at the Hershey Lodge in Hershey, Pennsylvania, in September. (Photo for The Washington Post by Calla Kessler.)