Feds track diseased cow's herd
Investigators hope test will find source.
Published Sunday, June 26, 2005
WASHINGTON (AP) - The government hopes DNA analysis can pinpoint the herd of the cow that tested positive for mad cow disease and lead investigators to the source of the animal's brain-wasting illness, the Department of Agriculture's chief veterinarian said yesterday.
Genetic testing is needed because of mistakes in how the beef cow was labeled and how its tissues were stored, John Clifford told The Associated Press in an interview
The cow, a "downer" that could not walk, was delivered last November to a plant where animals unfit for human consumption are killed. The department has not identified the owner or the plant.
The cow's breed was mislabeled, possibly because the animal had been heavily soiled with manure, and its tissues were mixed with tissues from other cows, Clifford said.
Parts from the diseased animal and four other cows were supposed to be kept in separate waste barrels, but some of the waste was combined, Clifford said.
Department officials think they have found the right herd. To confirm that, they must find relatives of the dead cow and test DNA.
Finding the herd will help track the cow's feed and explain how the animal became infected. The mad cow disease is only known to spread through the feeding of infected cattle remains to other cattle. The U.S. has banned this practice since 1997.
When he announced the mad cow test results Friday, Agriculture Secretary Mike Johanns pointed out U.S. cattle "move all across the country."
The new case was confirmed by an internationally recognized laboratory in England. A series of tests in the U.S. had produced conflicting results.
U.S. officials had declared the cow to be free of the disease in November, but the department's inspector general ordered a new round of tests that came back positive and led to the British tests.
Mad cow disease is the common name for bovine spongiform encephalopathy, or BSE. A form of the brain-wasting disease in people, variant Creutzfeldt-Jakob disease, is fatal and has been linked to the consumption of contaminated meat. The disease has killed about 150 people worldwide, mostly in Britain, where there was an outbreak in the 1990s.