BSE
From Tardis Wiki, the free Doctor Who reference
BSE was a condition in cows which caused them act strangely. Symptoms included heightened aggression and weight-loss. When reported it could lead to panic and result in cows being slaughtered.
Dr Scotus was called out to the death of a cow in South Wales, which he originally believed to have been caused by BSE. Upon autopsy, he discovered that it had an alien tapeworm in its stomach. (PROSE: Slow Decay)
Behind the scenes
In the real world, BSE is more commonly known as mad cow disease.