A British lab has provided initial independent confirmation that the United States has its first case of mad cow disease, US agriculture officials said. Federal investigators have been labouring to trace the path the infected animal took from birth to slaughter.
Scientists at the Veterinary Laboratories Agency in Weybridge, England, told the US Department of Agriculture (USDA) on Thursday that they concur with the reading of tests on the stricken Holstein cow that led US officials to conclude the animal had the brain-wasting disease, US officials said.
”We are considering this confirmation,” said USDA spokeswoman Alisa Harrison, adding that the English lab still will conduct its own test using another sample from the cow’s brain. Final test results on the cow from Washington state are expected by the end of the week, she said.
Professor Steven Edwards, chief of the British lab, said those results already have been given to the USDA. But Edwards refused to disclose whether the tests show that the animal had mad cow disease, also known as bovine spongiform encephalopathy (BSE).
Meanwhile, Harrison said, investigators were working through the holiday to prevent a potential outbreak of the deadly disease and to calm public fears about the food supply. Government officials have said there is no threat to the food supply because the cow’s brain and spine — nerve tissue where scientists say the disease is found — were removed before it was sent on for processing.
Humans can contract a fatal variant of mad cow disease by eating infected beef products, but experts say muscle cuts of beef — including steaks and roasts — are safe. Also hamburger ground from labelled cuts, such as chuck or round, poses little health risk, experts say.
”Even though this is Christmas Day, federal officials are working on the investigation,” she said.
The government is trying to find the herd the cow was raised with, since the cow likely was sickened several years ago from eating feed made partly from an infected cow. The incubation period in cattle is four to five years, said Dr Stephen Sundlof of the US Food and Drug Administration (FDA).
Authorities also want to know where the animals were transported and have narrowed their search to two unidentified livestock markets in Washington state, where the sick cow could have been purchased.
Government sources told The Associated Press that the cow lived since 2001 at the Sunny Dene Ranch in Mabton, Washington, a town 65km south of Yakima. Officials have said a dairy farm near Mabton is under quarantine and that its herd would be slaughtered if the mad cow diagnosis was confirmed.
Authorities also were scrambling to find where the meat cut from the animal was sent. The USDA already has issued a recall for 4 685kg of beef slaughtered on December 9 at a meat company in Moses Lake, Washington.
Agriculture Secretary Ann Veneman said the recall was an extra precaution.
John Stauber, the author of Mad Cow USA, said the government hasn’t done enough to keep BSE out of the country.
Cattle get sick by eating feed that contains tissue from the brain and spine of infected animals. The US has banned such feed since 1997.
”Here’s the problem, the feed ban has been grossly violated by feed mills,” Stauber said from Madison, Wisconsin.
In one such case, X-Cel Feeds, of Tacoma, Washington, admitted in a consent decree in July that it violated FDA regulations designed to prevent the possible spread of the disease.
Agriculture officials said that only two out of about 1 800 firms are not in compliance with the ban, a significant improvement since 1997.
Stauber also said he believes the ban is ineffective because it exempts blood from cattle, which Stauber said could transmit mad-cow type diseases. Government officials and industry executives have said there is no evidence that animals can be infected from the blood of other animals.
While government and cattle industry officials voiced assurances that the beef on American Christmas holiday tables was safe to eat, the biggest buyers of US beef around the world slapped bans on imports of the American product.
BSE is caused by a misshapen protein — a prion — that eats holes in a cow’s brain. A total of 153 people worldwide have been reported to have contracted the human form of the illness, according to the federal Centers for Disease Control and Prevention. — Sapa-AP