A group of pigs from Cher Pork Farms is seen in Lone Rock, Iowa, U.S., August 28, 2018. Picture taken August 28, 2018. To match…
FILE - A group of pigs from Cher Pork Farms is seen in Lone Rock, Iowa, Aug. 28, 2018.

CHICAGO - The largest U.S. meatpacking union celebrated a victory in federal court on Wednesday that it said invalidated a Trump-era rule allowing hog slaughter plants to run without line speed limits.

A lawsuit brought against the U.S. Department of Agriculture (USDA) by the United Food and Commercial Workers Union and three of its local chapters had challenged the 2019 rule change, arguing that faster slaughter speeds undermined worker safety.

The ruling from a federal judge in Minnesota will likely be criticized by the U.S. pork industry as it tries to rebuild supplies of meat after COVID-19 outbreaks shuttered slaughterhouses last spring.

Seaboard Foods, the second-biggest U.S. 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.

The 2019 rule change allowed pork plants to slaughter as fast as they want, as long as they prevent fecal contamination and minimize bacteria. Previously, the government imposed a limit of 1,106 pigs per hour.

President Joe Biden's administration, which pledges to prioritize worker safety, quickly withdrew a Trump administration proposal to allow all poultry plants to operate faster-than-established line speed limits. But reversing the pork rule was expected to be trickier, lawyers and analysts said, because it was already in effect.

A USDA spokesperson said the agency is reviewing the court decision "closely in light of the authorities, mission and mandate of the Food Safety and Inspection Service (FSIS)."

The 2019 elimination of pork line speeds by the USDA was part of the New Swine Inspection System, which also lets pork plants use some company inspectors instead of USDA ones. Those rules were stayed by the U.S. District Court of Minnesota, giving the new administration 90 days to rewrite the policies.