North Carolina ranks second in total poultry production. Senator Hagan, a Democrat from Greensboro, was joined in her letter by 12 other senators, both Republicans and Democrats.

The change would allow plant employees to check carcasses for defects and perform other quality-assurance tasks. That would free up federal inspectors to focus on sanitation standards, blood testing and antimicrobial controls, Hagan’s office said in a news release.

The USDA said when it introduced the rule in January 2012 that the shift would save money and improve food safety. The senators' letter, released to The News & Observer, said that a risk assessment concluded 5,000 foodborne illnesses per year would be prevented if the system was changed in this way, saving about $80 million in health care costs annually.

The new system was tested over 14 years at 25 poultry plants and found to work as well or better than the traditional system of having federal inspectors look at each carcass, according to reports submitted to support new rule, the letter said.

The change also is estimated to save $14.6 million in government spending in the first year and savings of about $39.6 million in subsequent years.

The USDA hasn’t updated the inspection standards since 1957.

Bob Ford, executive director of the North Carolina Poultry Federation said his group supported the rule change.

The senators' letter asked Vilsack when he would submit the rule as required for approval by the White House Office of Management and Budget and how long it would take to implement the rule when it became final.