Deer: Wasting disease disaster
  1. Sick in the brain
2. Prion eyes
3. Disease on the move
4. Effective eradication?
5.Deer gobble plants



What is this Swiss-cheese brain disease?







These deer may look innocent, but they may carry a dangerous brain disease. U.S. Fish & Wildlife Service.


Mad cow, meet mad deer
8+ point whitetail buck stands partially behind treeState authorities are planning to kill 15,000 deer in the hills of southwest Wisconsin. The reason? A mysterious brain disease closely related to mad cow disease.

White-tail buck, Oak Ridge National Laboratory.

Chronic wasting disease, AKA CWD, bores holes in the brains of deer and elk. They slobber, stagger, shake, stumble and salivate. Then they waste away and die.

Chronic wasting disease has afflicted deer and elk in Colorado and Wyoming for decades. Within the past five years, it apparently jumped 1,000 miles east to Wisconsin, home to The Why Files, 600,000 deer hunters and about as many white-tailed deer.

Many observers consider the outbreak a horrific threat to deer, and perhaps other animals. "If we leave it alone, it will expand its range," says Judd Aiken of the University of Wisconsin-Madison. "It will no longer be a problem just in Wisconsin, but also in Illinois.

"If we do nothing, you will have CWD-infected animals, with very high levels of infectivity. This is not a good thing."

(CWD and mad cow are members of a bizarre class of diseases called the TSEs, for transmissible spongiform encephalopathies. Aiken studies the strange proteins, called prions, that cause the TSEs.)

Beyond deer, the disease threatens deer hunting. In the past 60 years or so, hunting has emerged as a key rural ritual, bonding families and generations. It's also a mainstay of rural economies during fall, the deer season.

And because other animals eat deer and deer carcasses, the CWD epidemic poses the threat of "jumping species." TSEs already infect at least eight mammal species in nature, says Aiken, also including sheep, cattle, goats, mink, cats and elk.

Confused by the lingo? Check our glossary.

The alarm rang in February, when three deer shot the previous fall tested positive for CWD. The state Department of Natural Resources then hunted 500 deer in the area. Lab examinations of their brains revealed 11 more infections.

4 deer, big ears up and out, peer through the tall grasses at the camera

Mad cow message
Chronic wasting disease is less familiar than its close relative, mad cow disease. Ignored by Britain's agricultural authorities, mad cow caused a scandal in 1996. Britain's beef industry was practically destroyed when the government admitted what critics had been warning for a decade -- that eating sick cows was not healthy for kids and other living things.

Eating beef or other parts of mad cows is now blamed for more than 100 cases of the human brain disease, Creuzdtfelt-Jacob Disease, or new-variant CJD.

To prevent an epidemic, hundreds of thousands of British bovines were slaughtered in 1996. Unfortunately, globalization has taken its toll: mad cow has shown up in cattle on the continent. They were presumably infected by shipments of live animals or feed tainted by remains of mad cows.

3 elk stand, 1 lies down on dry grassy plain. Hills in background Elk and deer can both get chronic wasting disease. U.S. Fish & Wildlife Service.

Cognizant of Britain's economic disaster, Wisconsin authorities decided not to tarry, but rather to eradicate -- kill -- every deer in a 328-square mile region west of Madison.

Fearful that an unchecked epidemic of CWD would decimate deer, rural areas, and an entire way of life, they have also ramped up investigations of chronic wasting disease.

Facing a pending disaster like this, we Why Filers admit to being as fascinated as a sleazy lawyer at a highway accident. Are sick deer dangerous to people who love venison? Would a falloff in deer hunting change the landscape ?

And what is this Swiss-cheese brain disease ?



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