BOSTON -- Team 5 Investigates exposed horrific conditions inside a Minnesota puppy mill that has supplied thousands of dogs to pet shops all over the country. NewsCenter 5's Sean Kelly reported on Monday that one of those shops, located in Oxford, Mass., did business with that breeder for years.

Video | Photos: Local Pet Owners

Four families came to a stark realization. The sick dogs they bought at Laughlin Kennel in Oxford had a horrific start at a New York Mills, Minn., puppy mill run by Kathy Bauck.

"Kathy Bauck does not care she is breeding dogs that are sick, that are deformed and dying," said Beth Christman, of Warren, Mass.

Christman said her dog Gertrude, a St. Bernard, has double hip dysplasia. "Her hips are out of socket all the time. She lives in pain every day."

Ginger was infested with parasites. "I'm just glad I got her out of that environment," said her owner, Susan Bussow of Nashua, N.H.

And Aimee went from bad to worse. "She wasn't eating. She wasn't drinking. She would chew her feet raw, I mean right to the bone," said her owner, Rose Marie Laramee, of Ludlow, Mass..

All of the puppies were sold at Laughlin Kennel, which purchased dogs from Kathy Bauck for more than a decade. Now Bauck stands accused of animal cruelty and torture based on incidents of abuse documented in undercover video shot by an investigator for the Companion Animal Protection Society and turned over to police earlier this year.

"They're condoning the mistreatment of dogs in puppy mills. It's all about making money and taking advantage of unknowing customers," said Deborah Howard, President, C.A.P.S.

The state bureau of animal health inspects Laughlin every year and despite a stack of complaints dating back to 1993, it's still in business. Complaints obtained by Team 5 Investigates claim the kennel is dirty and overcrowded, the animals aren't cared for and are sold with diseases. While the kennel's owners have addressed many of those complaints, the complaints keep coming in.

"They told us they not only used, you know, qualified breeders, that they did not come from puppy mills," said Janine Meunier, of Uxbridge, Mass.

Meunier said she saved two sick dogs. "You go to look at that dog, it's covered in feces, it's covered in urine, it's disgusting. You can't go downstairs where they keep everything. They don't allow you down there."

So Team 5 Investigates went undercover to check out the animals' living conditions. But just like other customers, the sellers brought the puppies to us and refused to let us see where the animals are kept.

Team 5 Investigates tried to get answers from the kennel's owners. But when we paid them a visit, they were nowhere to be found.

But the Finks did send us an e-mail and provided us with a statement that answers to some questions. They don't consider Kathy Bauck's operation a puppy mill because it's licensed by the U.S.D.A. And they said they stopped buying dogs from Bauck back in June because of the animal cruelty charges she faces. They also told Team 5 they won't rule out buying animals from her in the future as long as she's cleared of all charges.

As to the reason why they won't let customers see where the animals are kept, they said they don't want to encourage "impulse" buying.

"It's frustrating for me as an animal control officer not to be able to do anything," said Sheila Donahue, the town of Oxford's animal control officer. Donahue said she's tired of receiving complaints about sick dogs being sold at Laughlin. Earlier this year, she stopped one of Bauck's trucks making a delivery there.

Inside the truck, she found puppies stacked in cages without any mats to prevent their feet from falling through. A problem regulators have cited both Bauck and Laughlin for in the past. "And they had some bottles with yellow water which indicates to me they probably were on antibiotic water," said Donahue.

Donahue was so frustrated she e-mailed town officials last year expressing outrage and embarrassment that the kennel has been allowed to stay in business.

Kelly: "Do you think Laughlin should be able to operate?

Donahue: "If it was my call, I don't think I'd be too quick to renew their license."

But that decision isn't up to the town. It's up to the state department of agriculture and the man in charge, Commissioner Doug Petersen, who told Team 5 Investigates he doesn't see any problems.

"We see them more often than other pet stores simply because of the volume of animals they sell and when you sell that many, a certain percentage of those are going to be sick," said Petersen.

"So just because they sell a lot of dogs means they're allowed to continue selling sick dogs?" asked Kelly. "We look at the trend lines of every single pet store to see if they were selling dogs that are more unhealthy than others, this particular pet shop doesn't show that," answered Petersen.

It was not exactly the response customers said they expected. They said they believe the state could do more to protect the animals. "I do believe they are turning a blind eye to the problem," said Christman.

Laughlin told Team 5 Investigates all of the dogs mentioned in this report were healthy when they were sold. And the kennel did refund Beth Christman after her dog was diagnosed with hip dysplasia. As for Janine Meunier and her two dogs, the kennel said she never tried to get her money back.

But Meunier denies that claim. An attorney for Kathy Bauck said his client runs a clean operation and treats all of her animals with the care and compassion. And he charges that the CAPS investigator created situations to portray bad conditions.