Reuters reports that the decision issued on 31 March in US District Court in Minnesota could raise costs for meatpackers like Seaboard Foods and Clemens Food Group and slow meat production after COVID-19 outbreaks in slaughterhouses limited output last year.

A lawsuit brought against the USDA by the United Food and Commercial Workers Union had challenged the 2019 rule, arguing that faster slaughter speeds undermined worker safety.

A federal judge said there was no evidence the Trump era rule had evaluated worker safety. USDA says it is evaluating the decision.

The North American Meat Institute, which represents meat companies, said it was disappointed in the verdict. The institute has argued that line-speed increases have not correlated with increased injury rates.

"We would like to see the agency appeal and ask for a stay," the institute said.

Seaboard Foods, the second-biggest US pig producer after Smithfield Foods, sped up its Guymon, Oklahoma, pork plant last year, becoming the first company to operate under the new rule. Workers told Reuters the faster line speeds increased injuries at the plant.

Seaboard did not immediately respond to requests for comment on 1 April.

The rule change allowed pork plants to slaughter as fast as they want, as long as they prevent fecal contamination and minimize bacteria. The US court stayed its decision to vacate the rule for 90 days, giving companies and the Biden administration time to adapt.

The elimination of line speeds was part of the New Swine Inspection System, which also lets pork plants use some company inspectors instead of USDA ones.

Tyson Foods Inc will press ahead with plans to implement the system over the coming months at plants in Madison, Nebraska, and Perry, Iowa, spokeswoman Liz Croston said. The company is focused on modernizing inspections and food safety, not line speeds, she said.

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