LANSING, Mich. (AP) - Michigan farmers and animal rights advocates are fighting over the treatment of farm animals, a conflict that ultimately may be taken to voters.

The farm lobby is backing bipartisan legislation that would put into law the agriculture industry's guidelines for farm animals' health and welfare, and require audits of livestock farms. A 10-member council would review and possibly update animal care standards at least every five years and local governments would be pre-empted from setting their own rules.

Upset by what it calls the industry's "blatant power grab" in the debate, the Humane Society of the United States is threatening a 2010 ballot initiative to give farm animals in confined spaces more room. Voters passed similar proposals in Arizona, California and Florida. Governors and lawmakers also enacted measures in Colorado, Maine and Oregon.

Supporters of the Michigan bills say people want to know more about where the ir food comes from, particularly in the wake of food recalls. Workers at a since-closed California slaughterhouse were caught on videotape abusing weak cattle to force them to slaughter, leading to the country's biggest beef recall last year.

"It really is about consumer confidence, protecting the food chain and safety of the food chain," said House Agriculture Chairman Mike Simpson, D-Jackson, who wants his committee to approve the legislation by month's end. The first committee hearing on the bills held last month drew so many people wanting to speak that it was extended another day.

While the proposed law would apply to farms both big and small, attention is centering on the state's 200 industrial livestock farms that house and feed hundreds or thousands of animals in enclosed spaces. Those are known as concentrated animal-feeding operations.

"We would like to phase out extreme forms of confinement," said Paul Shapiro, senior director of the Humane Society's factory farming campaign. He said many pregnant pigs are housed in 2-foot-wide crates barely larger than their bodies throughout the four-month pregnancies.

Specifically, the country's biggest animal welfare group says calves raised for veal, breeding pigs and egg-laying hens should have enough room to stand up, lie down, turn around and extend their limbs.

If existing industry standards are written into state law, there would be a minimum 67 square inches of cage space per bird - two-thirds the size of a sheet of paper.

"They can't spread their wings, they can't walk, they're virtually immobile," Shapiro said.

Letting the ag industry oversee itself with "paltry" guidelines would be like having "foxes guard the hen house," he said.

The Michigan battle, along with one in Ohio, are continuations of a debate that ramped up in 2008, when the Humane Society successfully waged a ballot campaign in California giving hens, pregnant pigs and veal calves more living space. Nearly $20 million was spent for and against that proposal.

Farming organizations and their friends in the Legislature do not want to see a ballot initiative here.

"This is Michigan, not California. We're not going to allow an outside group to come into Michigan and give chickens the right to drive cars," said Simpson, a sponsor of the House bills with Rep. Jeff Mayes, D-Bay City. Sens. Wayne Kuipers, R-Holland, and Gerald Van Woerkom, R-Norton Shores, have introduced identical Senate bills.

Simpson said the Humane Society wrongly equates farm animals with humans, and most farms comply with national science-based animal safety standards developed by the ag industry. The bills would help nab "bad actors," he said.

Tonia Ritter, governmental affairs manager with the Michigan Farm Bureau, said the legislation takes a "holistic" view of the food supply instead of a "very narrow" one focusing only on animal rights.

The Humane Society argues its proposal is "modest" and would be approved by at least six in 10 voters if supporters collect signatures to put the rules on the 2010 ballot.

By DAVID EGGERT, Associated Press Writer

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