Two major hamburger chains and dozens of school districts around the nation have banned meat from a Chino slaughterhouse after a video showed workers brutalizing sick and crippled cows, officials said Friday.

Altogether, more than 150 school districts in California, Arizona, Hawaii, Utah, Montana, Minnesota, Washington and other states have stopped using ground beef from Hallmark Meat Packing Co. and its associated Westland Meat Co. until completion of a federal investigation.

The New York City public school system — the nation's largest with 1.1 million students — pulled all hamburgers from its menus.

"It's just as a precaution; we haven't seen any problem," said Department of Education spokeswoman Margie Feinberg.

The schools still are offering beef salami and beef bologna, along with chicken, fish and cheese.

Two major fast-food chains, Jack-In-the-Box and In-N-Out, said they would not use beef from the Chino slaughterhouse.

Jack in the Box, a San Diego-based company with restaurants in 18 states, told its meat suppliers not to use Hallmark until further notice, spokeswoman Kathleen Anthony said.

"We definitely have very strict animal welfare guidelines that we expect our suppliers to follow," she said.

Jack in the Box does not purchase meat directly from slaughterhouses, so it was unclear whether it had used any Hallmark meat, she said.

In-N-Out, an Irvine-based chain, also halted use of the beef, saying it would never condone the inhumane treatment of animals.

A call to Hallmark seeking comment was not immediately returned Friday.

Westland President Steve Mendell said Wednesday that the company was "shocked, saddened and sickened" by the video, had fired two workers shown in it and suspended their supervisor.

No illnesses linked to the beef have been reported.

McDonald's Corp., the world's largest fast-food chain, does not do business with the slaughterhouse, spokesman Walt Riker said in an e-mail Friday.

Burger King, based in Miami, does not buy beef from the packing house and "we have no connection to the supplier," spokeswoman Denise Wilson said.

A videotape released Wednesday by The Humane Society of the United States showed employees at the Chino slaughterhouse kicking, shocking, dragging and otherwise abusing "downer" cows — those believed too sick or injured to walk.

The society urged passage of Congressional bills that would require downed animals to be killed humanely and bar them from being slaughtered for human consumption.

USDA regulations already prohibit use of disabled cows for human food because they may pose a higher risk of illnesses such as mad cow disease.

However, regulators said they were not immediately able to determine from the video whether the workers were forcing downer cows into the slaughterhouse or dragging them out of the line.

Westland sold more than 27 million pounds of beef last year for use in school lunch and other federal nutrition programs.

Agriculture Secretary Ed Schafer has said there was "no immediate health risk" from the meat but added his department had barred any more purchases or use of the slaughterhouse meat for federal programs until the probe was completed.

Federal inspectors were at the packing plant on Friday, USDA spokeswoman Angela Harless said.

The California Department of Education had urged districts to be cautious until they could confirm their beef did not come from the slaughterhouse.

The Los Angeles Unified School District pulled ground beef products from the menu after getting a federal warning, but the change will "almost be invisible to the kids" because fish, chicken and other food choices will be available for the up to 500,000 daily lunches, said Dennis Barrett, the district's director of food services.

"No one will starve," he said.