Life’s never been sweeter for a hound dog. In a parallel, online universe, floppy-eared canines, along with cats, monkeys and other critters, soak in hot tubs, lounge about in pink tutus, dine on chocolate pudding and relieve themselves in porcelain toilets.

Welcome to the land of Webkinz, the toy craze that is transforming how children interact with that old classic, the stuffed animal. Each pint-sized creature arrives with a “secret” code that, when punched into the Web site http://www.webkinz.com, gives birth to a digital alter ego.

Using virtual cash earned through game-playing, kids must make sure the online versions of their pets have food, attention and the requisite creature comforts. “Mmm to the mmmax!” the virtual version of a cuddly gray elephant, tottering in ballet slippers, says in a cartoon bubble after being fed.

They’re an early lesson in caregiving, social networking and the ease of online consumerism all wrapped into one. And as with many toy fads, not everyone thinks they’re a good thing. But that apparently isn’t slowing down sales.

“They are truly the hottest things going,” said Tracey Orrico, manager of Blue Tulip, a Wilton, Conn., gift shop. “At first it was like, oh, those are cute stuffed animals. It was overnight, boom, every kid had to have a Webkinz.”

Orrico said she is greeted each morning with phone messages from Webkinz-seeking customers, asking when the next shipment will be delivered.

The plush animals can’t be found at Toys “R” Us or Wal-Mart; they are sold exclusively at independent toy shops and high-end gift stores, according to Jim Silver, editor-in-chief of Toy Wishes magazine.

Unleashed in a year ago, the pets didn’t morph into a national phenomenon until a few months ago. Word spreads from playground to playground, a child’s version of a computer virus.

Ganz, the family-owned company that produces Webkinz, would not disclose sales figures.

New York-based toy consultant Chris Byrne says Webkinz have struck a nerve with today’s tech-savvy children.

“Play always reflects the culture,” he said. “It’s a social experience like Beanie Babies, but a global experience with the Internet. It allows the child to have very distinct play experiences that use different parts of the brain.”

Beatrice Landau, 8, of New York City, handed out Lil’Kinz, the Webkinz equivalent of Barbie’s little sibling, Skipper, at her recent birthday party. They were an instant hit among her friends, said Beatrice’s mother, Robin Landau.

Though Beatrice and her brother Sam, 10, spend more hours on the Webkinz site than they do playing with the actual animals, Landau said she doesn’t limit their computer time.

“I’d prefer they do that than watch television,” she shrugged.

At roughly $12 apiece, Webkinz are often cheap enough for children to buy. Beatrice and her friend Aliona Maitland, 8, peddled their baby books in Central Park to drum up a few extra dollars for more animals “We’d already read them all,” Beatrice said.

A mini-capitalist economy unto itself, the Webkinz world expects children to provide financially for their pets’ survival.