No abnormal prion protein detected in the milk of cattle infected with the bovine spongiform encephalopathy agent.

Milk specimens were collected from lactating cows that had previously been challenged with bovine spongiform encephalopathy (BSE)-infected brain at 4-6 months of age. One group of 10 animals received a single oral dose of 100 g, a second group received 1 g and the third was made up of unexposed controls. The cows were inseminated artificially, and calved at approximately 2 years of age and annually thereafter.