"In essence, the case confirms what was already known about an extremely low level of BSE infectivity having existed in Canada's feed system during the late 1990s and early 2000s," the CFIA said in its final report on the investigation.

The British Columbia purebred dairy cow, reported in May with bovine spongiform encephalopathy or mad cow disease, was fed rations that were processed at a feed mill that also handled material fed to pigs and poultry, the agency said.

BSE is spread when cattle eat feed that includes protein rendered from diseased livestock. Pigs and poultry were allowed to eat feed made from cattle protein until a ban on the practice came into effect earlier this month.

The CFIA said the feed mill had procedures in place to prevent contamination of cattle feed, but it did not document procedures used to clean a receiving system and trucks that were used to haul ingredients for both types of feed, areas where the contamination most likely occurred.

The mill regularly received protein from four rendering plants, including one that supplied ingredients to each feed mill identified in previous BSE cases, the CFIA said.

Source: Yahoo! News