Humane Society of the United States An image from an undercover video taken for the Humane Society of the United States shows a dog called "Shy Guy" that was part of an experiment on dental implants at Georgia Regents University.

A grim undercover video showing researchers performing “painful … unnecessary” dental implants on dogs has landed a small Georgia university at the center of an intensifying debate over medical research involving live animals.

The video, which the Humane Society of the United States said was taken by an unidentified investigator, shows dogs under anesthesia having teeth pulled out and dental implants inserted at Georgia Regents University in Augusta. Eventually, the animals were euthanized and sections of their jaws removed for study.

Actress Kim Basinger narrates as a thin dog named “Shy Guy” shivers after surgery. Later it shows euthanized dogs, their necks flayed open during autopsy, as sections of their jaws are removed.

Since it was posted on YouTube on Nov. 20, the video has been viewed more than 35,000 times and stirred controversy on the 9,000-student campus. It prompted a protest last week across the street from the university, and a second is planned for Dec. 7. One first-year biology student who aspires to be a veterinary student told the Aiken Standard that she intends to transfer to another school after seeing what was going on there.

“What kind of veterinarian would I be if I stuck at a school that was potentially abusing animals? That goes against everything I'm for,” Hannah Kellems told the newspaper.

The Humane Society alleges that the experiments on the six animals were “painful” and “unnecessary,” and filed complaints with the U.S. Department of Agriculture and the National Institutes of Health’s Office of Laboratory Animal Welfare. It also accused the university of providing inadequate care during the research and of procuring the dogs from a dealer facing a USDA complaint that he improperly acquired animals.

"Dogs don't need to die for frivolous dental experiments,” said Wayne Pacelle, president and CEO of the society. “It's painful to watch these forlorn dogs sacrificed for these questionable purposes.”

The video below claims to show the suffering and death of dogs used in the research. Warning: This video may be disturbing to some viewers.

Kathleen Conlee, the society's vice president of animal research issues, said that the dental implant research, while legal, could have been accomplished without the use of dogs.

“There’s no justification there,” she said. “The condition is not life-threatening in humans.”

The university strongly denies the charges.

“The allegation that this research is strictly cosmetic, silly, or frivolous could not be further from the truth,” Mark Hamrick, the university’s senior vice president for research, wrote in an email to NBC News. “In this study, researchers were testing an antimicrobial coating that could help prevent dangerous infections in the gums and bones of the mouth.”

(See a statement from Georgia Regents University.)

Georgia Regents University obtained 186 dogs from animal dealer Kenneth H. Schroeder from 2005 to 2012, the Humane Society said, citing documents it obtained from the university and the USDA. The six used in the dental implant research arrived in November 2012. The surgeries were conducted in March, and the dogs were euthanized in May, according to the documents.

In the statement last week, the university said that the surgeries were performed under anesthesia and that pain control was provided afterward.

The USDA in September filed a complaint against Schroeder, alleging he improperly obtained dogs, impeded efforts to inspect his operation in Wells, Minn., and provided substandard care for dogs there. NBC News could not reach Schroeder on Tuesday or Wednesday. There are no allegations that the dogs that Georgia Regents bought were improperly obtained.

He is one of only six random-source Class B animal dealers left in the U.S., down from 11 in 2009. They typically acquire animals from breeders, shelters, auctions and “bunchers,” who collect animals from random sources. The Humane Society alleges that such dealers often get animals through unscrupulous means or without proper certification.

“We’re seeing pets ending up in laboratories,” Conlee said.

Some institutions avoid these dealers because of such issues. “We do not deal with Class B dealers, period,” said Charlie Powell, public information officer for the College of Veterinary Medicine at Washington State University in Pullman, Wash.

While Georgia Regents is feeling the wrath of pet lovers and animal activists, it is a small player in the use of dogs in medical research.

Pharmaceutical and biomedical companies use many more dogs in experiments, according to USDA data. New Jersey-based Covance used more than 5,000 dogs in research at its facilities in each of the 2011 and 2012 reporting years. In 2012, more than 1,100 of those dogs fell into “Column D” -- the category that the USDA’s Animal and Plant Health Inspection Service defines as “experiments … involving accompanying pain or distress to the animals and for which appropriate anesthetic, analgesic, or tranquilizing drugs were used.”

But universities and colleges across the country also use dogs in research. For instance, Central Carolina Community College reported using 50 dogs in its programs in 2012 – more than twice as many as the 22 that Georgia Regents University used. In 2011, Duke University reported using 1,158 in its programs, including 101 in “Column D.” Last year, Duke’s use of dogs fell to 213, according to USDA records.

But Globe University, a private institution based in Minneapolis that offers veterinary and health care degrees, reported an increase in its use of dogs over the past four years, from 355 in 2009 to 1,371 in 2013, according to numbers on file with the USDA.

Conlee, of the Humane Society, cautioned that such numbers might include animals that were spayed or neutered for local shelters or individuals as part of training programs.

She allowed that some research using animals might be necessary – for now.

“There is some life-saving research out there. We accept that it’s happening today,” she said. “We urge that we move away from using animals in research.”

Helen Diggs, director of laboratory animal resources at Oregon State University in Corvallis, Ore., said any university has rigorous protocols for approving animal research. “Before we say yea or nay about a specific project, we want to be sure that we’ve really thought about this, that this is the right species to be using,” she said.

And Powell said that the use of dogs is a necessity in research for products or procedures to benefit dogs. Still, he said, he understands the reaction to the video taken at Georgia Regents University.

“You can imagine pain in your mouth, and you imagine a nice fuzzy dog, and it becomes pretty repulsive,” he said.

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