Mad cow disease is the common term given to bovine spongiform encephalopathy (BSE), a prionic disease that leads to neurological dysfunction in cattle. The disease has various forms in other animals, including scrapie in sheep, chronic wasting disease in elk, and Creutzfeldt-Jacob disease in humans.
Prions are misfolded proteins resistant to destruction with regular anti-pathogenic agents and cause destruction to the tissue in which they occur. In Mad Cow disease, the prions cause cavities to form in the brain tissue, leading to a spongy appearance and loss of neurological function. The animals become lethargic and "mad", then die.
Prions are relatively new pathogens in the scientific world - discovered in the 1990s, studies are ongoing to understand how they spread and how they can be treated. Mad cow disease in Britain has led to bans on meat exporting and changes in feed customs, and recent cases in the U.S. and Canada have resulted in changes to how food safety is approached at meat processing plants: No meat headed for consumption can come into contact with nervous system components or remnants, so-called "downer" cows are not allowed in the food supply, and animals cannot be fed bone meal or remnants.
Image: Vacuoles in the brain tissue of a cow with BSE, taken by the US Dept of Agriculture
Write
Topic Rating: 57
