Mad cow disease found in US
United States authorities have reported the country's first case of mad cow disease in six years.
The US Department of Agriculture reported the country's fourth case of bovine spongiform encephalopathy (BSE) in a Californian dairy cow, but stressed the outbreak was contained and no meat had entered the food chain.
The first US mad cow case in late 2003 caused the nation's beef exports to drop by nearly $3 billion the following year.
BSE cannot be transmitted through milk.
"USDA remains confident in the health of the national herd and the safety of beef and dairy products. As the epidemiological investigation progresses, USDA will continue to communicate findings in a timely and transparent manner," agriculture department officials said.
Wait and seeTwo major South Korean retailers have suspended the sales of US beef, saying they would wait to see what action the government takes.
The country's Agriculture Ministry said they would take "appropriate" steps but stressed that the latest case was not directly connected to beef that can be imported by South Korea.
Authorities in Japan said there had been no policy change, and Taiwan authorities said they were monitoring the situation but had not yet decided whether to take action.
A spokesperson for Singapore's food regulator said import requirements were "sufficiently robust" to protect against contamination and that it would not be taking any further action.
The European Union said it had no plans to impose restrictions on US beef imports.
"[The discovery will] not impact the 16,000 tonnes of beef imported every year from the United States," EU health and food safety spokesman Frederic Vincent said.
US beef imports to the EU amount to 133 million euros ($US176 million) a year.
'US beef is safe'US beef producers were keen to prevent a panic.
"The most important message is that US beef is safe," said Philip Seng of the US Meat Export Federation.
According to the organisation, US beef exports are worth more than $342 million each month, with Mexico, Canada, South Korea and Japan among the main export markets.
The United States has an estimated 90.8 million head of cattle, forming a large chunk of the economy in states like Texas, Nebraska, Kansas and California.
Around 40,000 US cattle are tested by the Department of Agriculture each year.
More than 190,000 cases of mad cow disease have been detected in the European Union since it was first diagnosed in Britain in 1986, forcing the destruction of millions of cows.
More than 200 people around the world are suspected to have died, most of them in Britain, from the human variant of the disease, which was first described in 1996.
Scientists believe the disease was caused by using infected parts of cattle to make feed for other cattle.
Authorities believe eating meat from infected animals can trigger the human variant of the fatal brain-wasting disease.