CINCINNATI — Almost as comforting as the soft sweaters made from alpaca fleece is the affection that the llama-like animals from South America bestow on their owners. Jeff Pergram’s alpaca, named Masterpiece, would trail and nuzzle him.

So it was heartbreaking not only to Pergram, but also to owners throughout the state known as “Little Peru” for its thriving alpaca industry, when Masterpiece was stolen, beaten to death with a makeshift club and dumped in a barn.

“I can’t imagine anyone looking into the gentle eyes of an alpaca and doing such a thing,” said Beth Kressin, an alpaca owner in Medina, in northeast Ohio.

Two 17-year-old boys are charged in juvenile court with animal cruelty and other counts, and a 23-year-old woman is charged with complicity offenses. A judge has ruled that one of the teens should be tried as an adult, and a hearing on the other teen’s status is scheduled today.

There doesn’t appear to be a broader trend of attackers taking advantage of alpacas’ trusting nature, but the Ohio attack has rippled through the national network of alpaca ranchers even though most believe their pastures are well-fortified.

“This was tragic, but I think it is an isolated case,” said Jerry Miller, spokesman for the national Alpaca Owners and Breeders Association. Still, “it might make some owners keep an extra eye open.”

The attack is still discussed at alpaca shows, and owners and others have registered their distress on websites such as a “Justice for Masterpiece” Facebook page, which has drawn thousands of comments.

Smaller but similar in appearance to llamas and to camels without the humps, the long-necked alpacas are prized for their fleece, which is made into sweaters, socks, rugs, blankets, even teddy bears. They are raised also for breeding and show.

The fiber varies in price according to market demand and use. It can bring $2 or more an ounce in the raw state, with finished products sometimes costing more than $1,000.

Prices of the animals vary according to fleece, heritage and breeding characteristics. Some lower-quality alpacas sell for $250 to $300, while others sell for thousands of dollars, said Jeff Bradford, president of the Ohio Alpaca Breeders Association. One sold at auction this year for $675,000, he said.

Ohio leads the country in registered alpacas with 25,000. More than 150,000 alpacas are registered in the United States, according to the national association, based in Nashville, Tenn.

Typical security measures to protect alpacas from the likes of coyotes, dogs or mountain lions include 5-foot, no-climb fences and guardian animals such as livestock dogs, llamas, or donkeys, Miller said.

Masterpiece’s owner did not have a high fence or animals to protect the few alpacas at his Butler County farm about 40 miles north of Cincinnati. Pergram has sold his other three alpacas partly because of the January attack.

Masterpiece, worth $8,000, was part of his livelihood but also a gentle and lovable pet, said Pergram, who has received hundreds of sympathetic cards and e-mails.

There have been media reports through the years of humans needlessly killing farm animals, including horses, cows, llamas, sheep and goats. Animal welfare groups such as the Humane Society of the United States don’t track such slayings and believe they are less common than those involving dogs and cats.

Someone killed Tana Ward’s 5-day-old alpaca, Arianne, in 2007.

“I came home one day from work to find her in the pasture, decapitated,” said Ward, who owns an alpaca farm in Walworth County, Wis., about 45 miles southwest of Milwaukee. “We think it was kids, but there wasn’t enough evidence to bring charges.”

She now has dogs for protection and empathized with Pergram through the Facebook page.

“My heart broke when I read about the loss of Masterpiece,” she wrote. “Condolences and hugs to his family.”

Debbie Zulli, an alpaca owner in York Springs, Pa., said she believes her alpacas are adequately protected by the larger llamas and a high fence.

“But if someone wants to do something like this,” she said, “they will probably find a way.”