WASHINGTON — The country’s largest meatpackers successfully lobbied the Trump administration in the early months of the coronavirus pandemic to keep processing plants open despite knowing the health risks to their workers, according to a congressional report released on Thursday.

The report, prepared by a select House committee, describes the extent of the meat industry’s influence on the administration’s response to the pandemic: Companies stoked “baseless” fears of an imminent meat shortage in an effort to prevent plant closures. The legal department of Tyson Foods drafted the initial version of an executive order President Donald J. Trump issued in April 2020 declaring processing plants as “critical infrastructure.” And industry concerns prompted the government to adjust its federal recommendations on worker safety at a meatpacking plant.

Representative James E. Clyburn, Democrat of South Carolina and the chairman of the committee, said the findings underlined the companies’ interest in prioritizing production over the health of their workers.

“The shameful conduct of corporate executives pursuing profit at any cost during a crisis and government officials eager to do their bidding regardless of resulting harm to the public must never be repeated,” he said in a statement.

About 59,000 workers at meatpacking plants contracted the virus from March 1, 2020, to Feb. 1, 2021, and 269 eventually died, the committee said in October.

Meatpacking companies and trade groups pushed back on the findings.

The report “distorts the truth” and “ignores the rigorous and comprehensive measures companies enacted to protect employees and support their critical infrastructure workers,” the North American Meat Institute said.

The report is based on 151,000 pages of documents; over a dozen calls with meatpacking workers, union representatives and former government officials; and staff briefings with the Occupational Safety and Health Administration and the Agriculture Department.

Slaughterhouses, where people work in proximity, became major hot spots in the early weeks of the pandemic. Plant closures led executives at Smithfield Foods and Tyson Foods to issue public warnings in April 2020 that the country was at risk of running out of meat.

But data shows that a record amount of pork was exported to China that month. In emails obtained by the House committee, Smithfield’s chief executive noted that there was “plenty of meat” for export, and a representative at the North American Meat Institute described the warnings as “intentionally scaring people.”

The report also details how industry representatives enlisted top Trump administration officials in dissuading workers from staying home and softening federal guidance to address coronavirus outbreaks at meatpacking plants.

In an April call, for example, the chief executives of meat companies asked the agriculture secretary at the time, Sonny Perdue, for the president or the vice president to convey to workers that “being afraid of Covid-19 is not a reason to quit your job and you are not eligible for unemployment compensation if you do.”

During a White House news conference four days later, Vice President Mike Pence urged food workers to “show up and do your job” and assured them that the administration was “working with all of your companies to make sure that your workplace is safe.”

The report also described Mindy M. Brashears, the former under secretary for food safety at the Agriculture Department, as the meatpacking industry’s “go-to fixer.” Ms. Brashears, according to the report, at times used her personal phone number and email to connect with industry representatives — a potential violation of record-keeping rules.

Neither Mr. Perdue nor Ms. Brashears immediately responded to requests for comment.

The House committee also obtained documents showing that Smithfield executives engaged top officials at the Agriculture Department to suggest changes to federal health recommendations for one of its facilities in South Dakota in April 2020.

Compared with an original version obtained by The Washington Post, the final guidelines from the Centers for Disease Control and Prevention included qualifiers like “if feasible” and “whenever possible.”

Dr. Robert R. Redfield, the former C.D.C. director, told the committee that he had added the qualifiers “because he was persuaded by industry concerns” relayed by Mr. Perdue and his understanding of an impending meat shortage.

Jim Monroe, Smithfield’s vice president for corporate affairs, said in a statement that the “concerns we expressed were very real.”

“Did we make every effort to share with government officials our perspective on the pandemic and how it was impacting the food production system? Absolutely,” Mr. Monroe said.

As states and local governments began enacting their own lockdowns, the meatpacking industry sought a workaround by proposing a federal directive invoking the Defense Production Act. Smithfield and Tyson held calls with the chiefs of staff to both Mr. Trump and Mr. Pence, and Mr. Trump’s executive order “adopted the themes and statutory directive laid out in Tyson’s draft,” the report said.

The executive order did not require meat processing plants to stay open but reduced the legal liability for the companies if they adhered to coronavirus guidelines.

In a statement, a spokesman for Tyson, Gary Mickelson, said that the company “has been contacted by, received direction from and collaborated with many different federal, state and local officials — including both the Trump and Biden administrations — as we’ve navigated the challenges of the pandemic.”