By Tom Polansek
CHICAGO (Reuters) – U.S. farmers will be able to test large quantities of milk from their dairy cows for bird flu instead of milk from individual cows before allowing them to ship across state lines, the Agriculture Department said on Thursday, in an effort to expanding testing.
The change shows how government officials are trying to contain the disease while minimizing economic damage to farmers after the bird flu virus spread to cows and three dairy workers since late March. But some vets warn that the bulk tests may be insufficient.
The United States Department of Agriculture (USDA) began requiring lactating cows to test negative before being shipped across state lines in late April. It later said the order likely helped prevent the spread of the virus to new states.
USDA reported 2,492 pre-movement tests on Wednesday, but said this number does not equal the number of animals tested.
A pilot program to test bulk milk aims to reduce the burden of pre-shipment testing while reducing the spread of the virus, said Eric Deeble, USDA acting senior adviser on bird flu. Farmers can sign up for it the week of June 3, he told reporters on a call confirming details of the program first reported by Reuters.
USDA expects the number of herds testing positive may increase because of the voluntary program and wants to encourage more testing, Deeble said.
“This program does not ease restrictions,” he said.
Agriculture officials in six states told Reuters on Wednesday they were reviewing USDA’s plans for the program.
USDA has confirmed the H5N1 virus in cattle in nine states. The U.S. Food and Drug Administration estimates that 20% of U.S. milk supplies show signs of the virus, suggesting wider spread is likely.
“Once it has the support and participation of farms, the USDA program could help reduce the threat of H5N1 in dairy herds, further reduce risks among farmworkers, and continue to protect our nation’s commercial milk supply,” the International Dairy said Foods Association in a report. statement to Reuters.
Farmers said testing milk from bulk storage tanks offers the chance to collect a sample from all cows in a herd and would be more efficient than testing samples from individual animals.
Under the new program, farms with herds that test negative using bulk bulk milk samples for three consecutive weeks can move livestock without additional testing prior to the move, according to USDA. Farmers must then submit weekly milk samples from bulk tanks to maintain their status, according to the agency.
USDA said in documents seen by Reuters that it could achieve disease freedom in states or regions if enough farmers participate. If a herd tests positive in the program, there would be an epidemiological investigation and movement review for animals considered low risk, according to the May 24 documents.
The program would mainly benefit large dairy farms that move animals, veterinarians said.
However, three weeks of testing milk from bulk tanks is not enough to confirm that a flock is free of bird flu, says Gail Hansen, a veterinary and public health consultant. Samples from healthy cows can dilute samples from a small number of infected cattle in the same herd if their milk mixes in the tank, she said.
“It can give people a false sense of security,” Hansen said.
USDA said it is identifying states that want to participate in the pilot program, while state officials said they have questions about how it will function.
“Indiana’s biggest concern is: How will the information collected be used? “Any discovery in Indiana could put us in the category of affected states, subjecting Hoosier producers to more severe restrictions from other states,” said nicknamed Indiana State Veterinarian Bret Marsh. for citizens.
Michigan, which has the most confirmed livestock infections, is interested, said Tim Boring, director of the state Department of Agriculture and Rural Development. The last two dairy workers to test positive were in Michigan.
“One of the basic safeguards here is limiting the movement of animals,” Boring said. “The last thing we want is to move sick cattle across different farms and spread the disease further.”
