Updated

It's the nightmare of pet lovers everywhere: Their beloved Fido or Whiskers gets lost, is scooped up by animal thieves, then sold to be dissected in a university research lab.

The Humane Society of the United States estimates that every year middlemen known as "Class B" animal dealers round up about 18,000 dogs and cats through flea markets and free-to-good-home ads, and then sell them to laboratories and university research labs.

In the process, it says lost pets are rounded up, too.

Now that Congress has undergone a change in leadership, the animal advocacy group hopes lawmakers will make it illegal for "Class B" dealers to sell "random source" cats and dogs to research labs.

The proposed ban is dubbed "Buck's Bill" in honor of Buck, a black hound dog seized in 2003 in Oklahoma from a dealer. Buck, who had heartworm disease and other ailments, died of internal hemorrhaging months after his rescue, while in foster care.

Mary Hanley, the executive vice president of the National Association for Biomedical Research, said she sees no reason for the law change. There may have been past abuses, she said, but it's not the current reality; Labs are required to keep documentation on where their research animals came from.

"Research facilities take great care," Hanley said. "They don't want dogs that they don't know where they came from. They take great care so that they do know."

Pennsylvania Reps. Phil English and Mike Doyle disagree.

"Lost or stolen animals may be getting in the queue for experimentation" without their owners' knowledge despite laws designed to prevent that, said English, a Republican who sponsored a House bill with Doyle, a Democrat.

Under their bill, labs would still be able to obtain research animals from breeders, pet owners who donate them, or shelters as long as the animal in question is not a stray. The bill is still pending before both the House and Senate agriculture committees.

The Department of Agriculture estimates that there are about 10 to 20 Class B dealers that sell to labs — far fewer than in the late 1970s and early '80s when there were more than 1,000 such dealers.

The states with Class B dealers that provide animals to labs are Arizona, Illinois, Indiana, Kentucky, Michigan, Minnesota, Missouri, North Carolina, Ohio, Oklahoma and Pennsylvania, according to the Humane Society.

Doyle said the Department of Agriculture doesn't have the money to ensure that the dealers are complying with animal welfare laws. Undercover work by outside groups has found evidence of animals being mistreated by Class B animal dealers, he said.

Darby Holladay, a USDA spokesman, said he could not comment on pending investigations or legislation.

A House agriculture panel held a hearing on the subject of animal welfare last week, which Wayne Pacelle, the Humane Society's CEO, said was a good sign that the Democratic-controlled Congress may take legislation like this seriously. The committee's last serious look at animal welfare was in 2000, he said.

An estimated 90,000 dogs and cats are bought by research facilities and veterinary schools each year. The Humane Society estimates that 70 percent comes from breeders, 20 percent come from Class B dealers, and 10 percent come from pounds.

Sen. Daniel Akaka, D-Hawaii, sponsored the bill in the Senate.