North Bay ranchers and farm officials voiced fears Monday that the weekend recall could force Rancho to permanently shut down.

"Without it, our producers would be really hard-pressed to stay in business," said Sonoma County Agricultural Commissioner Tony Linegar.

On Monday afternoon, numerous cars and trucks were parked outside Rancho's office off Petaluma Boulevard North. Several people could be seen on the premises.

A few black-and-white cattle stood in a lot toward the front of the rambling, hilltop property, and a government vehicle was parked outside a grey USDA office. Two employees, who did not give their names, said an attorney had advised everyone at the company, including the owners, not to comment.

The issue came to light Jan. 10 when federal agents, accompanied by Petaluma police, searched Rancho's plant as part of an ongoing investigation. Three days later, the USDA announced Rancho was recalling 41,683 pounds of meat that was produced on Jan. 8 and didn't receive a full federal inspection.

The plant shut down for a few weeks. It reportedly had restarted its processing operation or was about to do so when the recall was expanded Saturday to cover 8.7 million pounds of meat.

On Monday the USDA released a partial list of companies that have been asked to return meat connected to the recall. The 13 retailers — all in Sonoma, Marin and Napa counties — include: G&G Market stores in Santa Rosa and Petaluma; Bud's Meats in Penngrove; Petaluma Market in Petaluma; Willowside Meats, Carniceria Coalcoman, Carniceria Contreras and Carolina Wild, all in Santa Rosa; Sonoma Market in Sonoma; Brown's Valley Market, La Morenita and Vallergas Market, all in Napa; Apple Market in Novato; and Azteca Market in San Rafael.

Some stores, including G&G and Sonoma Market, said they no longer had any products in stock from Rancho. G&G CEO Teejay Lowe said the company has bought veal but not beef from Rancho.

Jamie Downing, general manager at Petaluma Market, said the store pulled what little meat it had from Rancho as soon as it learned about the recall over the news Sunday. The market was contacted by the slaughterhouse on Monday morning, he said. He said the market gets about $100 worth of meat each week from the facility.

"We pulled the stuff as soon as we heard," Downing said, adding that he is still trying to learn more. "Like any other recall, all we can do is react."

The recall also is affecting Marin Sun Farms, a local producer of grass-fed beef from Point Reyes National Seashore.

"Marin Sun Farms is in the process of carrying out recall instructions provided by Rancho Feeding Corp.," Daniel Kramer, the company's chief operating officer, said in a statement. He didn't elaborate on what actions the company was taking in response.

Among those questioning the government action Monday was longtime cattle buyer Ken Maffei of Petaluma. Maffei said he has known Amaral and Singleton for 35 years and the two men would not knowingly slaughter diseased or unsound animals.

"Show me evidence," Maffei demanded. "It's all hearsay."

He contended that federal regulators were "overdoing it to the max" with a year-long recall.

A spokesman for the USDA in Washington did not respond to a series of questions submitted Monday about the recall. The agency did not clarify how the meat could have received USDA inspection marks without full inspection. Nor did it explain the basis for its assertion that diseased or unsound animals were slaughtered at the plant.

According to a USDA press release, the recalled meat can be identified because both the beef carcasses and offal boxes bear the establishment number, "EST. 527," inside the USDA mark of inspection. Each box bears the case code number ending in "3" or "4."

Adam Parks, owner of Victorian Farmstead Meat Company in Sebastopol, said he couldn't understand the logic of a year-long recall because nearly all the meat already has been consumed. Nonetheless, he will reach out to customers who purchased grass-fed cattle that he had processed at Rancho during the affected dates.

Parks, who purchases cattle from ranchers, acknowledged it will be "an incredible expense and inconvenience" if Rancho closes and he has to ship all his beef to Eureka or the Central Valley for processing. Even so, he insisted such a closure wouldn't be the death knell for the North Coast beef industry.

"We'll survive it," Parks said.

Staff Writer Heather Irwin contributed to this story.