Spongiform encephalopathy is a progressive neurological disorder of cattle and thought to be caused by tiny particles called prions.
Mad cow disease is the bovine form of a condition that began appearing in British cows in the 1980s. Some were pathologically nervous, others bizarrely aggressive, but when the “mad cows” died, as they inevitably did, their brain were discovered to be shot through with holes.
The first confirmed case among US cattle occurred in December 23. Canada’s first case emerged in May 2003, prompting the US to stop Canadian beef imports.
Most cattle are infected when they ingest (oral) prion contaminated “ruminant” meat and bone meal contaminated with prions.
Bovine Spongiform Encephalopathy is typically a slow developing disease. Infected cattle appear normal for 2 to 8 years. As the disease develops, the brain is affected. Signs such as trembling, stumbling, swaying and behavioral changes (e.g., nervousness, aggression or frenzy) are seen. The disease causes damage to the brain cells which take on a sponge-like appearance. This physical damage results in loss of coordination, dementia, and, eventually death.
Mad cow disease
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