INDIANAPOLIS (AP) — Indiana lawmakers appeared to move a bit closer to a compromise on a contentious bill to regulate large-scale dog breeding operations on Thursday — the same day a group of pet lovers brought their dogs to the Statehouse to demand a crackdown on so-called puppy mills.

Both the House and Senate have approved versions of the bill to regulate dog breeders. The Senate plan would require breeders to comply with U.S. Department of Agriculture regulations if they have more than 20 adult female dogs able to be bred.

The House version outlined specific standards of care — such as providing dogs with sanitary conditions, exercise, light and ventilation — instead of using the USDA regulations. It would limit breeders to 30 adult female dogs that are not spayed.

Lawmakers on a joint House-Senate conference committee are working to see whether a compromise can be reached before the legislative session ends Wednesday. House bill sponsor Rep. Linda Lawson, D-Hammond, told committee members Thursday that she was willing to use the Senate version with some changes as a basis for a new compromise.

"I've given up quite a bit," Lawson said.

Sen. Brent Steele, R-Bedford, said the House version would have hurt the multimillion-dollar dog breeding industry in Indiana. He said he was happy to see the limit on female breeding dogs removed in the proposed compromise, although he said he wanted to give everyone involved a chance to look it over before passing judgment on it.

"It's nice to see there was some movement," Steele said after the meeting. "I wasn't expecting that, quite frankly."

Lawson's proposed compromise would make some changes to the Senate version of the bill. For example, it would require breeders to provide their dogs with a chance for exercise outside their cages at least once a day, and would require cages to be large enough to allow "reasonable movement." The proposal would also toughen animal cruelty and neglect laws and would allow dogs kept in wire cages to have solid ground to stand on.

Lawson said she made concessions in a spirit of compromise, and was hopeful that lawmakers could reach an agreement before Wednesday. It's unclear when the committee will meet next.

Earlier Thursday, nearly 50 people gathered on the Statehouse steps, with some holding signs and others holding dogs rescued from so-called puppy mills. They urged lawmakers to pass a strict version of a proposed breeding regulation bill.

Terri Scott came to the Statehouse with her dog Tiko, a toy poodle she said was rescued from a northern Indiana puppy mill. She said Tiko was used for stud service at the breeding facility and spent most of his life in a wire cage, and didn't receive veterinary care that could have prevented dental problems and blindness in one eye.

Scott said dog breeders shouldn't be regulated by the same standards used for farm animals.

"This is a dog, not a hog, not a cow," Scott said. "This is a dog — a companion animal."