http://www.washingtonpost.com/wp-dyn/articles/A60331-2004Jan6.htmlDNA Tests Trace Infected Holstein to Canada
By Shankar Vedantam and Deneen L. Brown
Washington Post Staff Writers
Wednesday, January 7, 2004; Page A08
DNA tests prove that a Washington state Holstein cow found infected with mad cow disease was born and likely infected in Canada, U.S. and Canadian government officials said yesterday.
Tracking the first case of mad cow disease detected in the United States to a farm in the province of Alberta solves a thorny problem for investigators -- it points to a potential source of infection and suggests that U.S. safety regulations may have successfully prevented the transmission of the dreaded disease within this country.
But the results also deepened the mystery of how the disease might have spread in North America, and raised fears that other animals may have become infected and entered the food supply.
For example, 97 cattle were sent to the United States starting in August 2001 from the same Alberta herd as the infected Holstein. Officials do not know where 86 of the animals are. <snip>
next days story:
http://www.washingtonpost.com/wp-dyn/articles/A60265-2004Jan6.html