image is the DNA imprint of the Mad Cow Disease.
Brains as feed
Mad cow disease
is thought to have originally come from sheep infected with scrapie, and contracted
by cows who ate feed made from -- among other things -- sheep's brains or
spinal tissue. A standard practice in the feed industry, carcasses from sheep,
cows, chickens and pigs are boiled, ground and mixed into feed for those animals.
Sheep brains and spinal tissue infected with scrapie were fed in this way
to cows, and when they died their infected brain or spinal tissue was spread
to other cows. Humans were infected through eating cow brain or spinal tissue
via hamburgers, hot dogs, and sausages.
In the U.S., feed containing brains and spinal tissue has been banned since
1979 from being fed to cattle or sheep (but not to pigs or chickens). Despite
the ban, food mills have not always been careful to adhere. McDonald's,
wanting to avoid revisiting its European losses, is apparently demanding
stricter procedures in this area.