Gov. Mark Dayton has declared a state of emergency over a bird flu outbreak that has killed more than 2.5 million turkeys in Minnesota and has for the first time this week stricken a Minnesota chicken farm.

The governor's order activates an emergency operations plan to support the state's response to the epidemic. It also calls for National Guard personnel to be ordered to duty as needed, but the governor is not calling up troops.

Minnesota is the nation's largest turkey producer, and 45 commercial farms have now been hit by the highly pathogenic H5N2 virus, including one more announced Thursday. Also, the first Minnesota outbreak in a "back yard flock" of poultry — 151 birds — was reported Thursday in Pipestone County.

And a farmer in northwestern Minnesota said Thursday that his egg-laying operation with 300,000 chickens has been stung by the flu.

"This is a moving target, and the number of farms affected has continued to increase," Dayton said. "We don't know what the ceiling will be."

Dayton said the order will tighten lines of authority in state and local government and allow his office to properly coordinate planning between the Board of Animal Health, the Minnesota Department of Agriculture and the Division of Homeland Security and Emergency Management.

The animal health board and state agriculture department have been on the front lines battling the virus, along with the U.S. Department of Agriculture.

The bird flu poses a low risk to human health and the H5N2 strain currently spreading across North America has not caused any illnesses in people. The 140 people in Minnesota who have worked directly with sick birds have been monitored by the Minnesota Department of Health. None has tested positive for bird flu.

State officials reiterated Thursday that the bird flu is not a food safety risk either. Sickened birds are destroyed, and turkey shipments are tested, said Dave Frederickson, commissioner of the Department of Agriculture. "The poultry on grocery store shelves is safe and will continue to be safe."

Animal health experts are hoping that warmer, sunny weather will stop the virus, at least for this spring.

The bird flu has appeared in 16 states, including striking a 3.8 million hen farm in northern Iowa — the largest single outbreak nationwide — and two more egg-laying operations in Wisconsin, which has also declared a state of emergency. Now, Minnesota's egg industry, the eighth largest in the nation, has become a victim.

Amon Baer said his J & A Farms, about 20 miles west of Detroit Lakes, must destroy roughly 300,000 chickens after testing on Monday confirmed the presence of the highly pathogenic H5N2 bird flu.

The animal health board said Thursday that the agency is aware of the "presumptive positive" at J & A Farms and is in the process of formal confirmation.

Because of its presence in other states' chicken flocks, animal health board spokeswoman Bethany Hahn said "it's not too surprising" that the bird flu would hit a chicken operation in Minnesota.

The state's farmers raise roughly 47 million chickens a year for meat and 11.4 million for eggs. Annual egg production in Minnesota averages nearly 3 billion. Turkey growers raise 46 million birds a year.

Baer said his father started the egg-production company in 1965, and his sons are also in the business. He is worried about the disease derailing the company financially.

"The requirements are that the entire [flock] be depopulated," Baer said. And while there is federal assistance available to cover some of the farm's losses, it doesn't come close to covering the entire expense, he added.

"This is something that is very expensive — cleaning, disinfecting in order to get permission to restock the facility," Baer said. "We have to prove that we don't have the virus anymore before we can repopulate."

Meanwhile, bird carcasses are piling up and disposal methods are being tweaked. The procedure has generally been this: Birds are composted on site in the barn for 28 days, and the heat in the compost kills the virus. The remains are often spread on farm fields.

Farmers, who lose money the longer their barns aren't hosting birds, are cutting in half the compost cycle inside the barns and finishing the composting outside. The compost pile would heat up to about 160 degrees in the barn, then be turned and moved outside to heat up again to completely kill the virus. Thus, the barn would be freed up quicker for a new batch of birds.

Also, some farmers are looking at burying their dead birds directly without composting. Such a method requires a grower to meet standards set by the Minnesota Pollution Control Agency and to get permission from the animal health board, said Dr. Bill Hartmann of the animal health board.

So far, one farmer has gotten permission for bird burial, he said.

Staff writer J. Patrick Coolican and the Associated Press contributed to this report.

Mike Hughlett • 612-673-7003

Paul Walsh • 612-673-4482