The end of the investigation leaves US officials not knowing what happened to 11 of the 25 cattle that authorities consider likely to have eaten the same potentially infectious feed given to the Washington state Holstein born from a Canadian herd.
'Of the 17 other cattle from the Canadian birth herd, seven animals have been identified in the United States,?/I> said the USDA this week.
The BSE cow slaughtered in Washington on 9 December, 2003, was born on a dairy farm in Alberta, Canada, on April 9, 1997. She then moved to the US in September 2001 along with 80 other cattle from that dairy. A brain sample collected from the cow at slaughter tested positive for BSE on 23 December, rounded up the USDA.
In response to the BSE crisis ?and arguably the fact that 11 potentially BSE-infected cattle are still roaming the food chain ?rule makers in the US this week proposed a mandatory livestock identification system to keep track of herd movements by being able to quickly identify animals suspected of carrying disease.
If the bill is passed, it would give the USDA 90 days to establish a nationwide, electronic livestock identification system that could track farm-raised animals, such as cattle, hogs, sheep and poultry, from birth to slaughter. The estimated cost of the project has been put at $175 million (€138m).