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Researchers: Wolves Might Slow Spread of CWD
William G. Davis writes "According to this AP article, researchers are now suggesting that wolves might be able to slow the spread of chronic wasting disease (CWD) in deer. Chronic wasting disease is the name commonly given to spongiform encephalopathy (prion disease) in deer and elk (basically, mad cow disease in deer). The article explains how wolves typically look for weaknesses in their prey, and since prion disease causes that, wolves might target the sick animals. One has to wonder, though, about the potential ramifications of having dangerous predators exposed to this brain-wasting illness, and what type of 'unusual behavior' they'll start to exhibit."
Wolves aren't particularly dangerous. They rarely attack humans... rarely ENCOUNTER humans for that matter, and being at the top of the food chain, wouldn't be in much of a position to pass the virus (virii?) on to other species. I'd guess any wolf that began to have symptoms of such a serious disease would simply starve to death in fairly short order.
To ensure perfect aim, shoot first and call whatever you hit the target
Had the submitter actually read up on CWD, they'd have learned that it's already present in areas where there are wild wolves, and that there's no sign of the wolf population contracting it.
As well, in tests that involved feeding infected brains to live stock, none of the livestock showed any signs of contracting CWD. The only time they've had sucess with transmitting the disease outside of deer and elk is by atricicial means, as in, directly injecting it into the brain.
So the wolves should be safe enough.
I had understood that "Mad Cow" is only transmitted by eating the brains of an infected animal. Ranched cattle would acquire it as they are sometimes feed the brains of previously slaughtered cattle, but how exactly do deer and other wildlife transmit it?
Is there another transmission vector, or do deer etc in fact eat the brains of their own dead?
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$tar -xvf
Was just talking about this with a coworker (who keeps track of this kind of thing - he's more of a "commodities geek")on Wednesday.
Sounded like people link these two diseases is that the end result looks the same. Chronic wasting disease is a muscle problem, Mad Cow disease is a deterioration of the brain. Both end up the same with a weak animal that can't walk.
Chronic Wasting disease is probably more of a problem brought on by the overpopulation of deer in the upper midwest than anything. Wolves (and other predators) will benefit until the deer are brought into a more sane population - then they'll turn on people.
A fine is a tax you pay for doing wrong and a tax is a fine you pay for doing all right.
Wolves aren't really so much "dangerous predators" as "your basic carnivores in the wild." They're not going to attack humans unless their other food options are totally depleted and they're starving.
/. is just wrong, and I'd encourage whoever is responsible to go to a site like www.defenders.org and donate a but of money to try to push the tide of public opinion back away from myth and towards truth.
Mad Wolf Disease would not cause this situation so much as make the wolf infirm and eventually dead. You're not going to have sudden blood-lusted and violent wolves. You're going to have very dead wolves who can't function.
Meanwhile, absurd paranoia like this will lead to an incrase in programs like the one they're trying really hard to put into place in Alaska, whereby they will slaughter all wolves in a given area with a 100 mile radius. By shooting them from helicopters. And sometimes, by chasing them via helicopter to the point of exhaustion, and then shooting them. Because apparently the helicopter and machine gun aren't enough on their own.
Short form - the "wolves are dangerous" myth is both ignorant and destructive, and whoever submitted this article (As well as whoever approved it) should be ashamed - spreading crap like this on as widely read a site as
Philip Sandifer's academic website
-from what I remember reading in some not-so-recent Scientific American, a scavenger's immune system wouldn't help protect against rogue prions, because they're neither virus nor bacteria. A scavenger, if it incorporated these same prions into their own bodies, could possibly also be at risk for mad foo disease.
No primates are vegetarians.
Well, strictly speaking, you're right. Most primates get a small amount of their protein by eating small animals, mostly insects. But this doesn't make them predators. In general, primates get most of their calories from plants, and have few if any adaptations for predation. They're more properly classified as omnivores.
Similarly, cattle and other grazing animals inevitably eat a small quantity of insect, snails, etc that are mixed in with the herbs. But this doesn't make a cow into a predator.
In addition to humans and chimps, there are a number of other primates that actively hunt prey. Baboons come to mind. There's also the fish-eating monkey in southern Asia. All four of these species get a significant amount of protein and calories by eating small animals. But most primate species get maybe 1% of their calories by predation, so they don't really qualify as predators.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
CWD is prevalent in ranching areas. I theorize that the deer and elk are eating livestock feed on occasion when the opportunity presents itself - a very common occurance.
Keep in mind that chicken and pork feed use ground up animal protein, including brains of down animals. All approved by the USDA. It is just cattle feed that is not supposed to contain animal protein. In fact in the Washington casem, i would bet that the cow in question at one time dined on swine feed.
Large numbers of dear and elk contact the disease simply because they live long enough for the disease to manifest itself (3 - 5 years)
Comforting is it not?
And there's lots of literature supporting the idea that predators and scavengers tend to have very good defenses against the diseases that affect their prey. Part of the defenses are powerful digestive systems that leave few cells intact and chop up most proteins and DNA into small pieces. They also have some of the best immune systems on the planet.
You can have the strongest immune system of any known mammal or bird and it will not protect you from prion diseases like spongiform encephalopathies. There is no foreign protein (except for the prion particle that you originally got infected from years ago), just a lot of funny-folded native protein. So what? As amyloid plaques build up in your brain, your immune system has nothing to attack. An infected animal's body can be riddled with prions at death and you will not find a single antibody to them anywhere since they pass the self/non-self test. In fact, to get antibodies, people need to inject massive quantities of prion particles into unrelated animals, whose immune systems will react in the same way they do with any foreign protein.
A strong digestive system doesn't seem to be much help either, as the prion form of the protein is extremely resistant to attack from proteases.
There are many versions of the prion gene, and not all of them are equally prone to malicious folding. Wolves with prion genes whose PrP proteins fold easily into the beta-pleated-sheet prion tend to die after eating lots of prions. Surviving wolves gobble prions and suffer no adverse consequences since their native protein is resistant to the altered conformation. So the wolf is probably OK, because of the selection pressure that has been applied to it.
But you'd think the same thing about cats, and cats get the disease easily. But in fact, it is highly likely that all wolves are immune to transmissable spongiform encephalopathies judging by the mere fact that nobody has ever succeeded in infecting a dog with any sort of TSE. Even when they plonk highly infectious prion material directly into a dog's brain, no TSE develops. TSE of one flavor or another has been successfully transmitted to goats, sheep, monkeys, pigs, mink, cattle, cats, and zoo animals of all types that ate prion-contaminated feed. Never to any breed of dog (or wolf, same thing).
When BSE broke out in England, a number of human victims (who all ate beef) came down with CJD. It was called "new variant" CJD ("nvCJD") because it turned out not to be CJD at all, which attacks the cerebral cortex, but is in fact a closely related disease: the human form of BSE, which attacks the brainstem just like it does in cattle. A prion researcher tried to transmit BSE from cows to transgenic mice which had a human prion gene, via brain injections (the foolproof way to get it- feeding is much less effective). This experiment was eventually watched closely by the British food industry as the mice survived past 300 and 400 days. But meanwhile, study of the first ten victims of nvCJD in Britain showed that all were homozygous for methionine at codon 129. About 38 percent of the human population fits this profile. The mice (which never showed any signs of illness) had a human prion gene that was homozygous for valine, not methionine, at codon 129. So while this is a transmissable disease, susceptibility is genetically determined.