Health

Milk from Minnesota dairy farms to undergo mandatory testing for bird flu

Dave Schwartz, who farms near Slayton, is just breaking even on milk.
A dairy cow on a southwest Minnesota farm. Minnesota will be among the next group of states to start mandatory testing of milk from dairy farms for the H5N1 virus.
Mark Steil | MPR News 2018

Agriculture officials next month will begin mandatory testing of milk from Minnesota’s dairy farms for highly pathogenic avian influenza.

The U.S. Department of Agriculture ordered national testing of raw milk in a federal order in December, beginning with six states. The testing has now expanded to 28 states, which produce nearly two-thirds of the nation's milk supply. 

The USDA says the goal of the testing is to gain a clearer picture of the presence of the H5N1 virus in dairy herds, and help inform response efforts to prevent it from spreading further.

Avian influenza has been confirmed in dairy cattle in 16 states, including Minnesota, which had nine cases last year. In California, more than 700 dairy herds have been affected, and Gov. Gavin Newsom declared a state of emergency in December.

“That’s really a concern, is a jump from poultry to dairy, so (we’re) wanting to make sure and assure the public,” said Thom Petersen, Minnesota’s agriculture commissioner. “Also, controlling the disease is really important too, because we’re seeing what’s happening in California.”

In Minnesota, the virus has been far more destructive to the poultry industry, where it has caused the deaths of millions of commercial turkeys and chickens as well as backyard flocks since 2022.

The disease isn’t fatal for most dairy cattle, but can cause low appetite, decreased milk production and thickened or discolored milk.

Petersen said they will begin testing milk from dairy farms around Feb. 1. The department will work with labs to pull samples of raw or unpasteurized milk that farmers already routinely submit for testing, so there’s not an extra burden to farmers, he said.

Petersen noted Colorado’s success with a mandatory testing program adopted last year.

“They were able to identify, work with the farmers and try to contain it as much as possible, and then get to where they had no cases,” he said. “That’s kind of the hope is to try to isolate as quickly as possible.”

Testing also allows the department to notify surrounding farms that the virus is in their area, especially if they have workers or vehicles moving from farm to farm, Petersen said.

Some farmers across the U.S. have been reluctant to test animals or milk, fearing economic repercussions. But in Minnesota, dairy farmers are on board with the state’s testing plan, said Lucas Sjostrom, executive director of the Minnesota Milk Producers Association.

“We want this disease stamped out, and USDA has determined that testing is the best way to do that,” he said. “We’re going to know where the disease is, if it’s present at all, and we’ll be able to stamp it out faster.”

Sjostrom said he supports Minnesota’s plan for testing every single dairy farm in the state by using samples farmers already are submitting once a month, rather than having officials visit farms or processors.

“When we’re worried about a disease like influenza, having more people at a farm or a processing plant is not ideal,” Sjostrom said.

It’s not yet clear what the testing will show. Sjostrom thinks it’s likely that there were more cases of H5N1 in Minnesota dairy cattle than were reported last year. Many of its symptoms are similar to other metabolic disorders than routinely occur on farms, he said.

Petersen said right now, there aren’t indications of the virus in Minnesota’s dairy cattle.

“We’re not seeing signs of the virus in the Upper Midwest at this time, but that can change quickly, and we need to be prepared for that,” he said.

Pasteurization, or heat treatment, inactivates the virus, so consuming pasteurized dairy products is considered safe. 

However, Minnesota law does allow the sale of raw milk on farms, and those supplies won’t be included in the initial testing, Petersen said.

“I do urge Minnesotans that do drink raw milk to have conversations with their farmers about what they’re doing to protect themselves as well,” Petersen said.