The investigation of the closed Rancho Feeding Corp. slaughterhouse comes as critics contend that U.S. Department of Agriculture staffing decisions and a shortage of inspectors have resulted in more food safety recalls because meat failed to receive a full inspection.

Food & Water Watch maintains that such recalls were rare until about three years ago, said Tony Corbo, a spokesman for the Washington, D.C., consumer advocacy group. But since 2012 there have been 15 of them, including by Rancho’s Petaluma facility, the group wrote in a July 14 letter to Agriculture Secretary Tom Vilsack.

USDA officials have publicly denied any connection between the recalls and the number of federal inspectors at meat processing plants.

But two emails between a top USDA official and the head of the union that represents the food inspectors reveals the agency was planning to increase the number of inspectors at “high-risk plants” in response to congressional frustration about Rancho and another incident in New Jersey.

The emails were detailed in an April 7 letter sent by Food & Water Watch to Rep. Robert Aderholt, R-La., who heads the House Agriculture Appropriations Subcommittee.

In a Feb. 13 email to the union, Keith Gilmore, the USDA’s executive associate for regulatory operations, suggested that the agency was being pressured by Congress to step up its efforts after problems surfaced at Rancho and the New Jersey facility, where an alleged incident of inhumane treatment took place.

“In both instances, our employees were in the plants, however were not in the pens at the time that these activities were occurring,” Gilmore wrote. “As a result, Congress is upset with the Agency, and we are being asked to address the situation.”

The proposed solution was to add more inspectors at high-risk plants that process large numbers of calves and older cows, with a goal of having “a permanent inspection presence in the pens.”

A second email on March 31 said the agency soon would announce 22 new inspector positions for 18 plants around the country.

Food & Water Watch said the issue of inspectors is important, in part because of parallels between the Rancho Feeding recall and a 2008 recall at the Hallmark-Westland facility in Chino, a plant that also slaughtered large numbers of older cows.

The resulting investigation at Hallmark focused on “some of the same issues raised in the Rancho Feeding recall,” Food & Water Watch Executive Director Wenonah Hauter wrote in the letter to Aderholt.

A USDA spokesman declined to comment on the letter this week.

The Hallmark recall came about after the Humane Society of the U.S. released videos of plant workers abusing weakened, downed cattle. The resulting investigation pointed out the need for adequate inspection of the health and the treatment of older cattle awaiting slaughter, said Michael Hansen, a senior scientist who follows the meat processing industry for Consumers Union, the policy and advocacy division of Consumer Reports magazine.

The Rancho case, said Hansen, suggests that six years later, “the government still hasn’t learned its lesson.”