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An African antelope imported into a British safari park in the 1970s may have
started mad cow disease. Most experts think BSE arose when a prion mutated
spontaneously, or because farmers fed cows remains of sheep infected with
scrapie, a disease similar to BSE. But Roger Morris of Massey University in New
Zealand says BSE may have developed after cattle ate the remains of an African
antelope, which is also susceptible to a disease related to BSE. Morris says his
computer models back the case, although he will not reveal further details until
his report is published in a scientific journal. The human form of BSE, called
vCJD, has already killed more than 90 people.