disease in 1986. The disease originated in the United Kingdom, when cattle feed was prepared from
sheep infected with their own version of the disease (Tortora, Funke, & Case, 20). In 1996, countries
all over the world began to refuse beef imported from the United Kingdom because hundreds of
thousands of cattle born after 1988 had to be killed for fear they may had been infected with the
disease (Tortora, Funke, & Case, 20).
Mad Cow disease is caused by an infectious protein called a prion. Prions are the cause
of neurological diseases (Tortora, Funke, & Case, 203). This can result in an organism losing its ability
to mentally and physically function properly (Hirsch). These prions are considered to be mutated and
cause transmissible spongiform encephalopathies (TSEs). TSEs are so named because the brain becomes
spongy (full of holes), the brain tissue withers, and uncoordinated movements develop in the affected
person or animal (Timby & Smith, 114).