Bovine spongiform encephalopathy and the safety of milk from Canadian dairy cattle.

The detection of bovine spongiform encephalopathy (BSE) in beef cattle closed Canadian beef export markets to 30 countries, including the USA, with devastating financial losses. The detection and confirmation of the fifth and seventh BSE-infected animals but first infected dairy cows extended the problem of risk management to Canadian dairy farmers. As the public are concerned about the safety not only of beef but also of milk and milk products that may contain disease-causing prions, this review examines the evidence for the safety of milk from studies on prions in milk or colostrum and their vertical and lateral transmission in various animal systems. The evidence indicates that the risk of contracting new variant Creutzfeldt-Jakob disease through the consumption of milk is negligible.