Recent tests have confirmed on Sunday a new case of mad cow disease on a farm in British Columbia's Fraser Valley, Canada's 5th case since 2003. "Our investigation has taken us back to the farm, which is known to us to be the birth farm of this cow, and we're in the process of assembling, through farm records, those herd mates that were of a similar age and likely consumed the same feed," said George Luterbach, a senior veterinarian for the Canadian Food Inspection Agency. Canadian officials suggested "there was probably contaminated feed being served to cattle in the early 2000s, so enforcement of the feed ban may not have been effective in Canada." A spokesman for the Agriculture Department replied "We said very publicly from the beginning that as we work with Canada we anticipated that there would be additional cases of (mad cow)." The animal discovered with the disease was a 6-year-old dairy cow, officials stressing the fact that "the disease is not transmitted ... from cow's milk, even if the milk comes from a cow with mad cow disease." The potential sources of infection are now being identified, especially the kind of foodstuff that was given to the animal. The surveillance program has tested more than 100,000 cows since 2003, when Canada's first case of bovine spongiform encephalopathy, or mad cow disease, was found in Alberta. Canada ships beef from younger cattle to U.S. markets and sends animals under the age of 30 months for "slaughter" in the United States. U.S. officials say their most recent case, reported in mid-March, was a beef cow in Alabama that was born 10 years ago, before the ban on brains and spinal cords of older cattle from use.