Canada has reported its first case of mad cow disease in a decade, sending shockwaves throughout the North American food industry and causing bans to be placed on exports of Canadian beef to several countries, including the US. On Friday a cow in Canada's main cattle-producing province, Alberta, tested positive for the brain-wasting disease bovine spongiform encephalopathy, which is also known as mad cow disease. The test was taken on 31 January after the cow was slaughtered.