By Betty Yu

TURLOCK (KPIX 5) — For pet owners it may come as an unpleasant surprise: The flea and tick products you use on your dog or cat are tested in labs on other dogs and cats.

The research animals are kept in cages for months, even years, and subjected to the potentially painful experiments. And one of the biggest such labs in California is right in our own backyard.

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It’s a row of old sheds behind a walnut orchard in the central valley town of Turlock.

“It looks like a horror house,” said nearby resident Erma. “It’s scary. I mean those dogs are crying.”

Young Veterinary Research Services is a registered USDA lab. Inspection records show more than 300 dogs and 100 cats living there. Residents have started a Facebook page hoping to get a look inside.

“We want to know that these pets are not suffering in any way,” Erma said.

But so far, no visits have been allowed. Research articles we found show big name pet product companies like Merial, Merck, Bayer and Pfizer use the private lab to test flea and tick products. “These are not benign procedures,” said Kathleen Conlee with the Humane Society of the United States. “These can be invasive protocols that even involve the death of animals.”

It’s all perfectly legal. In fact the government mandates that most flea and tick products be tested on dogs and cats.

We looked for David Young and his wife Corinne at their business address, which is also their home: A horse breeding facility called Revelers Ranch best known for holding jousting matches and lavish medieval parties. No answer there. Down the road at the “actual” lab, they weren’t exactly happy to see us, yelling at us to get out.

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We did reach Dr. Young over the phone and he declined our request for an interview because he says people have already made up their mind about animal testing as something inhumane and unjust.

After our phone conversation Dr. Young hired a public relations person. She referred us to a local vet who she told us “works closely with Young.”

But Dr. Robert Santos told us all he does is treat animals in the colony that get sick at his clinic. He told us he has never been to the lab, but knows David Young well: “He is a personal friend of mine. I can vouch for his character, him and Corie are very compassionate towards animals,” he said.

Last year USDA inspectors visited the facility three times and found nothing wrong.

But there are past citations that Dr. Santos agreed to look at: In 2010 for instance the USDA cited him for geriatric dogs, several of them underweight, walking with a stilted gait. His response: “ I don’t know what happened there but I can tell you geriatric dogs will walk with a stilted gait. We asked him if he thought that was normal. His response: “Well, yeah.”

He says research on dogs and cats may not always be pleasant, but it’s necessary. “I think it is fair to have a bit of diarrhea and vomiting to see if a drug is effective or too strong.” We asked him if it was really worth it. He never got a chance to respond. His PR person interrupted the interview, telling us he was late for a surgery appointment.

For residents, it’s frustrating: “Why can’t we have a camera go in there. That is all the community wants to see. Just show us.

David Young declined our request to tour inside the lab. His PR person at first offered to provide us company video. But after our interview she told us it would not be available.

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We reached out to all the manufacturers listed in this report. Only Bayer sent us a statement, saying: “Bayer’s principles for animal studies underline our commitment to the well-being of our study animals. We expect the same commitment from our external partners. Full information on Bayer’s principles may be found here.