George Raine, Chronicle Staff Writer

Lawmakers turned up the heat on the U.S. Department of Agriculture Tuesday for gaps in animal inspection at a Southern California slaughterhouse that necessitated a recall of 143 million pounds of beef, the largest beef recall in U.S. history.

Sens. Barbara Boxer and Dianne Feinstein, both California Democrats, have asked for investigations of the facility, the Westland/Hallmark Meat Co., a supplier to federal food and nutrition programs, into possible violations of laws intended to prevent animal cruelty and preserve food safety.

Boxer and Feinstein are also co-sponsors of legislation, introduced by Sen. Daniel Akaka, D-Hawaii, that would take that safety precaution one step further and require that nonambulatory - or downer - cattle be euthanized, although the proposal might be met with resistance because downer cattle can be successfully treated.

The senators said they are appalled by a video, distributed by the Humane Society of the United States, that showed animals treated inhumanely at the company's slaughterhouse in Chino San Bernardino County.

"It's so sad on so many levels," Boxer said Tuesday. "It's sad for the children whose health might be threatened" with tainted beef. "It's sad for the animals that deserve not to have their lives end like this."

The recall affects beef products dating to Feb. 1, 2006, that came from Westland/Hallmark. Secretary of Agriculture Ed Schafer said Sunday that the department has evidence that Westland/Hallmark did not routinely contact its veterinarian when cattle became nonambulatory after passing inspection, which is a violation of health regulations.

Downer cattle are barred from the food supply in the United States, as they may pose a higher risk of contamination for mad cow disease, E. coli or salmonella.

Notwithstanding her support of the legislation, Boxer said she would prefer the food safety issue be pursued on a dual track, with the bill and tougher enforcement of regulations that the Agriculture Department has responsibility for.

"I want to know why USDA cannot stop this conduct right now," said Boxer. "Clearly, it does not seem to be implementing regulations in a very effective fashion." She asked USDA to re-examine its inspection protocols and ensure that similar abuses are not happening at other plants.

"We are concerned that the incident reveals flaws in oversight of food safety program at USDA," said Scott Gerber, a spokesman for Feinstein.

Akaka has for several years sponsored the bill requiring downer cattle to be euthanized, and it may receive expedited Senate Agriculture Committee attention in the wake of the recall, said Jon Yoshimura, an aide to the Hawaii Democrat. "That is our hope," he said.

However, it probably will meet resistance because so many downer cattle are treated effectively and get back on their feet, said Dr. Robert Cherenson, a large-animal veterinarian in Turlock Stanislaus County.

"The problem is how you define downer," said Cherenson. "I've seen cows get up after two weeks. If this were the law, many downer cows would be euthanized needlessly because they get up within a reasonable amount of time," said Cherenson, a vet with Lander Veterinary Clinic, in Turlock.

Meanwhile, in Sacramento, the chairman of the California Beef Council, Jim Maxey, said the council supports the recall, but said "this situation is an isolated incident and something that our industry wholeheartedly disapproves and will not condone."

The council, which is the promotion, research and education arm of the California beef industry, believes the recall was done with an "overabundance of precaution," said Holly Foster, a spokeswoman. She noted that there has not been a report of an illness allegedly associated with the company's beef and that the recall was done as a precautionary measure.

Also on Tuesday, Chino police said they had arrested one of the meatpacking workers charged with animal cruelty in the case.

Daniel Ugarte Navarro was taken into custody Saturday at his Pomona Los Angeles County home on a warrant issued the day before, police spokeswoman Michelle Vanderlinden said. He was released Sunday on $7,500 bail.

Navarro, 49, was charged with five felony counts of animal abuse and three misdemeanor counts of illegal movement of a nonambulatory animal, San Bernardino County Deputy District Attorney Debbie Ploghaus said.

Navarro, who worked as a pen manager at the slaughterhouse, could face up to five years and eight months in prison if convicted, she said.

Luis Sanchez, 32, of Chino was charged with three misdemeanor counts and remained at large, Ploghaus said.

Both men were fired after the Humane Society released the video.