A Green Lake County-based dog breeding operation believed to be one of the largest in the country has agreed to sell its assets to the Wisconsin Human Society, which plans to find adoptive homes for some 1,100 of the facility's dogs.

The deal will take about 3,000 puppies off the market each year and close what critics of large-scale dog breeding call a "puppy mill."

Wallace Havens, 72, who has owned Puppy Haven Kennels near Kingston since 1974, said the deal was reached late Thursday night. He said he had first approached the humane society about selling his breeding operation seven or eight years ago as he looked toward retirement.

"If I could have my pick of anyone in the world to turn it over to, it would be them," Havens said.

Havens is selling just the dogs and the equipment used in his breeding operation but not the 20 acres of land the kennel occupies. Neither Havens nor the humane society would disclose the sale price but both said it was less than what it's worth. The assessed value of the improvements to Havens property is a little under $300,000, according to the Green Lake County treasurer's office.

Havens will retain ownership of the wooded property and said he's likely to rent it out.

In a statement released Friday, Margaret Stratton, president of the board of the Milwaukee-based humane society, said the society's purchase of the kennel is a "groundbreaking action ... unique in the humane movement" and "consistent with the Wisconsin Humane Society's mission to build a community where people value animals and treat them with respect and kindness."

Havens said dogs began leaving his kennel for the humane society's facility on Thursday and that it could be September before all the dogs are gone. The humane society said about 300 had been transferred as of Friday. It plans to spay and neuter all the dogs it gets. The group has veterinarians evaluating many of them in preparation for adoption, and said a challenge will be getting the dogs used to interacting with people.

Puppy Haven specializes in so-called designer dogs like puggles — a pug-beagle cross — and miniature St. Bernards. It sells most of its animals to pet stores, although the general public can buy them direct as well.

Critics of large-scale dog breeding operations say they are often poorly run and dirty, but that even the better ones are not ideal environments for a dog's social and emotional health.

State lawmakers have tried and failed in the past to enact legislation to regulate commercial dog breeders like Havens, most recently earlier this year. Puppy Haven is inspected annually by the U.S. Department of Agriculture, which said earlier this year that it hadn't had to take any enforcement action against the kennel, though there had been several instances when fencing and drainage did not comply to standards.

The humane society was careful in its public statements Friday not to directly criticized Havens' facility, but in a list of "frequently asked questions" did say "living conditions for dogs in mass breeding facilities do not meet the medical, social or emotional needs of dogs, making the purchase (of Puppy Haven) consistent with our mission to create a community that values animals and treats them with respect and kindness."

Havens defends the care dogs have received at the kennel, and a representative with the Wisconsin Retired Breeders Rescue club said in February it's far from the worst.

It was suspended and fined by the American Kennel Club in 2006, however, because of poor conditions there.

John Snyder, a vice president in the companion animals division at the U.S. Humane Society did not have access to any records on Puppy Haven Friday night, but did say that in general, large breeding operations are an "industry of misery."

"I've yet to see a (puppy mill dog) that's well cared for," he said.

Havens said seven full-time employees, including himself, and eight part-time employees will lose their jobs.

— The Associated Press contributed to this story.