The US Department of Agriculture is to appoint a global panel of scientists to review its response to the country's first case of mad cow disease.
Experts fear the case could cost the US cattle industry billions of dollars
Agriculture Secretary Ann Veneman also announced limits on beef production, including a ban on "downer" cattle entering the food chain.
"Downer" cattle are animals which cannot walk at the slaughterhouse, a common symptom of mad cow disease.
US officials confirmed last week a cow had been diagnosed with the disease.
The infected animal came from a dairy in the north-western state of Washington.
Ms Veneman said the panel would provide an objective review and identify areas for "potential additional enhancements".
In addition to banning downer cattle, processors will be barred from using the brains, eyes, small intestine and spinal cord of cattle in human food, Ms Veneman added.
Packing plants will also be prohibited from killing cattle using the air-injection stunning method to ensure portions of the brain are not "dislocated" into carcass tissue.
BOVINE SPONGIFORM ENCEPHALOPATHY
First surfaced mid-1980s
Can pass to humans through infected beef products
Human form of disease called vCJD
vCJD has killed 137 people, mainly in the UK
"The actions we are taking today are steps to enact additional safeguards to protect the public health," Ms Veneman said.
Ms Veneman added that the US was working towards implementing a "verifiable system" of national animal identification.
On Monday US authorities said they were trying to establish the origin of the feed that may have infected the stricken cow with BSE, or bovine spongiform encephalopathy, also known as mad cow disease.
SELECTED COUNTRIES THAT HAVE BANNED US BEEF
Canada - partial ban
United Arab Emirates
*Top three importers
Officials had said the meat from the infected cow, slaughtered on 9 December in Washington State, had only gone to Oregon, California, Nevada and Washington.
But now they are saying the beef could have gone to outlets in Alaska, Hawaii, Montana, Idaho and the territory of Guam.
Dr Ron DeHaven from the US Agriculture Department said the cow is believed to have been one of 74 imported from Canada into Idaho in 2001.
She had three calves after she entered the US, one of which died, while another remains in a herd in Washington state.
A third calf, a male, is reportedly being held in isolation with other animals.
It is not yet clear where the rest of the herd is or whether they are infected, Dr DeHaven added.
US experts have predicted that news of the BSE case will cost the US cattle industry billions of dollars.
At least 26 countries have now banned imports of American beef because of BSE fears.