BSE is a progressive and fatal neurologic disease of cattle believed to be caused by an unconventional transmissible agent, an abnormal prion protein. BSE belongs to a family of diseases known as transmissible spongiform encephalopathies (TSEs) that includes scrapie in sheep and goats, chronic wasting disease in deer, elk and moose, and in humans, classic and variant Creutzfeldt-Jakob disease (CJD) among other syndromes. The prion agent is resistant to enzymatic breakdown and most disinfection treatments. Clinical signs in cattle include behavioral changes, coordination problems, weight loss and decreased milk production. The incubation period from time of infection ………..until the onset of clinical signs averages three to six years.
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