HARRISBURG -- At a standing room-only hearing yesterday, animal rights activists clashed with dog kennel industry advocates in an emotional debate over a Rendell administration-endorsed rewrite of the state's dog law.

One lawmaker, Rep. Jim Cox, R-Berks, said the revision, intended to put an end to much-criticized "puppy mills," was receiving "rabid" opposition from kennel owners, who feared it would drive up the cost of their operations.

The hearing centered on House Bill 2525, which proposes the first changes to the state's dog law in 12 years. It was introduced by Rep. James Casorio, D-Westmoreland.

The Casorio bill would force commercial kennels to increase the space requirements for dog cages, stop using wire flooring in the cages, eliminate the stacking of cages, provide dogs with an annual veterinary checkup and guarantee dogs access to an outdoor exercise area.

"We are not trying to put commercial kennels out of business, but we are trying to raise the bar," state Agriculture Secretary Dennis Wolff said.

"For many dogs living in Pennsylvania's commercial kennels, 'legal' is not synonymous with 'humane'," said Cori Menkin of the American Society for Prevention of Cruelty to Animals.

The bill defines kennels as places that house more than 26 dogs in a year. A subset called "commercial kennels" is defined as establishments that sell or transfer more than 60 dogs in a year.

Opponents of the bill, including the Pennsylvania Farm Bureau and the Pennsylvania Professional Dog Breeders Association, argued the bill unfairly targets responsible commercial kennel owners.

They also said it unnecessarily exceeds the standards outlined in the federal Animal Welfare Act.

"There can be no mistake about it," Ken Brandt, a spokesman for dog breeders, said. "If this bill is enacted into law, the association believes that no existing kennel operation could ... meet the requirements."

In 2006, Gov. Ed Rendell attempted to tighten restrictions on commercial kennels by introducing regulations that agriculture department spokesman Chris Ryder said resulted in 16,000 comments from concerned kennel owners. The regulations were withdrawn last month and the bill is now attempting to solve the issue through legislative action.

Much testimony revolved around the issue of wire caging, which some critics claim can hurt dogs' paws.

Robert Lavan of the Pennsylvania Veterinary Medical Association said his organization opposes the solid flooring included in the bill because of sanitary issues. He said the type of caging shown in the ASPCA photos is "an extreme" and his colleagues support a tighter meshing.

"We believe there is a middle ground," he said.