HOLCOMB, Kan. — Each day 150 semitrailers loaded with cattle arrive at Tyson Food Inc.'s Holcomb plant for slaughter. Each day workers here butcher 5,700 head of cattle.

The hundreds of blood-spattered workers in the killing room and on the processing floor clean and skin and carve cow after cow until their eight-hour shift is done.

And each day at least one meatpacker at the plant gets hurt on the job.

For years, the 3,100 workers who toil here have accepted injuries as a risk of working in one of the nation's most hazardous occupations. Now they are seizing upon those injuries to buck a trend of low union participation that grew as the nation's meatpacking industry consolidated and drew more immigrant labor.

Ramon Sandoval, a 63-year-old Tyson worker, grimaced as he tried to make a fist with his swollen right hand. Nerve damage from the repetitive work cutting meat has injured it, and the company has since put him on light duty.

"We are fighting for justice, dignity and respect," he said.

Adopting farm labor organizer Cesar Chavez's rallying cry, "Si se puede!" ("Yes, we can"), immigrant workers have now taken on behemoth Tyson. On March 1, workers will vote on whether to unionize under the United Steelworkers union. The union would represent 2,450 workers in Tyson's Holcomb plant, about 80 percent of whom are Hispanic.

The unionization vote is the second recent challenge these workers have mounted. In May, Holcomb workers sued Tyson, alleging the company violated labor laws by not paying them for time spent putting on and taking off protective equipment.

The workers face a formidable opponent. Tyson is the world's largest processor of chicken, beef and pork — employing 114,000 people at 300 plants around the globe. Human Rights Watch reports that about 30,000 employees in 33 Tyson facilities are represented by unions.

Union membership and wages in the nation's meatpacking industry plummeted in the 1980s amid plant closings, lengthy strikes and deunionization struggles, according to a study by the Agriculture Department's Economic Research Service. Union rolls had remained stable through the 1970s, but fell from 46 percent of workers in 1980 to 21 percent in 1987, and has stayed at those lower levels.

The Holcomb workers hope bringing in the union will help slow the production line to ease repetitive strain injuries, while getting them better health insurance and retirement benefits.

Workers last year reported 452 job injuries and one death from work at the plant, Occupational Safety and Health Administration logs show.

Nationwide, about 47,500 workers in the animal slaughter and processing industry were hurt in 2005 while on the job, a rate of 9.1 injuries per 100 workers, Bureau of Labor Statistics data shows. That same year, 13 workers were killed.

The number of injuries has fallen by almost 70 percent since 1990, when the industry partnered with OSHA and the United Food and Commercial Workers union to develop ergonomic guidelines, said Janet Riley, spokeswoman for the American Meat Institute.

Plant manager Paul Karkiainen dismissed the latest unionization issues as the "same kind of rhetoric" as a failed effort in 2000, when 78 percent voted against two other unions.

Karkiainen said the number of injuries at Holcomb seems high because the company encourages workers to report all injuries and it's one of Tyson's biggest plants, at 1 million square feet. He contended that the rate of serious injuries is low, as seen by its lost-time rate.

The Holcomb plant has a safety committee, and every line has at least one safety committee member. Each worker is outfitted with $400 worth of protective equipment, Karkiainen said.

Tyson said it could not address the individual personnel matters cited by employees interviewed for this story since they are considered confidential. However, spokesman Gary Mickelson said Tyson routinely monitors carbon dioxide levels from the dry ice used in packing some meat products to comply with federal limits. The company abides by medical restrictions placed on workers by their physicians, he said, adding that Tyson has an open-door policy and encourages workers to bring concerns to managers.