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Researchers: Wolves Might Slow Spread of CWD 72

Posted by michael from the spongy-brained-wolves dept.
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."
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Researchers: Wolves Might Slow Spread of CWD More

Researchers: Wolves Might Slow Spread of CWD

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  • Dangerous? (Score:5, Insightful)

    by rot26 ( 240034 ) * on Friday December 26, 2003 @09:44AM (#7812187) Homepage Journal
    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.

    • Re:Dangerous? (Score:3, Interesting)

      by Tango42 ( 662363 )
      Being at the top of the food chain doesn't stop your corpse being eaten by scavengers, does it?

      • Re:Dangerous? (Score:5, Informative)

        by Micro$will ( 592938 ) on Friday December 26, 2003 @11:34AM (#7812749) Homepage Journal
        Scavengers typically have immune systems thousands of times powerful as humans.

        Quote from Here [guthriecenter.com] Vultures have long been perceived as loathsome birds because of their feeding habits. We now know the important role these birds play by cleaning up dead animals. The Latin name Cathartes aura means "Golden purifier". Turkey Vultures are immune to botulism, anthrax bacteria, hog cholera virus and many, many more that would kill other animals as well as us. Vultures were once blamed for spreading diseases. Scientific research has shown that their digestive tract and immune system actually destroy all pathogens and help to control these diseases. Ongoing research in the medical field on the Turkey Vulture's amazing immune system may some day yield valuable information that could be applied to humans as well as livestock.

        • However... (Score:2, Informative)

          by tsanth ( 619234 )
          -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.
          • I'd forgotten about savenger's immune systems, but now you mention it, i do recall hearing it before. You make a good point. As for prions, they are out of my field of knowledge, so i can't really say, but i would expect they are similar to viruses in detection, they are both sub-cellular organisms.

            • Re:However... (Score:3, Informative)

              by jasno ( 124830 )
              From About.com [about.com]:

              Definition: A protein particle that is capable of causing an infection or disease. Like viruses, prions are not capable of reproduction by themselves. Unlike viruses, prions do not contain genetic material (DNA or RNA).


              I think they're an example of a self sustaining molecule - one that catalyzes the creation of itself from another molecule.
              • That would make sense. I don't know how that would effect immune systems though... i would think it would be easy to the WBCs to "eat" the prions, but obviously it is more complicated than that. If they effect the brain they must be able to get through the barriers, which means they are very small (as you would expect for a single protein molecule), which would probably cause the immune system problems.
              • I think they're an example of a self sustaining molecule - one that catalyzes the creation of itself from another molecule.

                That's probably the best way to look at it. It's just like Vonnegut's ice-nine, except it works on a particular mammalian brain protein instead of water.

                Infective particles pass through 30 nm filters and survive immersion for long periods of time in formaldehyde. They are relatively impervious to radiation and can survive the heat of a rendering plant. Unlike the normal protein, the
          • at risk for mad foo disease.

            ::shudder::


            I don't know what I'd ever do with my Friday nights if they ever discovered a case of mad bar disease :)

            -

        • Hmmm, why don't they put Turkey Vulture genes in all our livestock? I'd eat 'em up! YUM YUM
          • Why waste time mucking aroud with genetic enginering when you could simply start raising Turkey Vulture livestock?

            Turkey Vulture! It's not just for Thanksgiving anymore!

            -
      • But scavengers have some of the toughest digestive tracks in the world.

    • Re:Dangerous? (Score:5, Interesting)

      by jc42 ( 318812 ) on Friday December 26, 2003 @12:12PM (#7813038) Homepage Journal
      I'd guess any wolf that began to have symptoms of such a serious disease would simply starve to death in fairly short order

      True. 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.

      The explanation is fairly simple. If you're a predator or scavenger, you often eat food that was weakened or killed by disease. This puts strong selective pressure on your species in favor of defenses against those diseases.

      I've read a couple of articles on the semi-exception that the top predator on the planet (Homo sap) seems to be a partial exception. This is generally explained as an artifact of our recent conversion to predation. We do have some predator adaptations, but we haven't had time to evolve them fully.

      There is a bit of debate about this, though. For example, studies of wild chimp populations haved turned up data showing that they actually do get a significant part of their protein by eating small animals. So our predatory ancestry probably goes back at least 5 million years. But still, we are primates, and it wasn't all that long ago that our ancestors were vegetarians.

      • BS (Score:1)

        by hummassa ( 157160 )
        No primates are vegetarians. Don't do that.

        • Re:BS (Score:3, Informative)

          by jc42 ( 318812 )
          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
          • [i]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.[/i]

            Sure does, if you are a snail.

      • Re:Dangerous? (Score:4, Interesting)

        by Alsee ( 515537 ) on Friday December 26, 2003 @04:27PM (#7814464) Homepage
        There is an interesting twist on this with Komodo Dragons. Their mouth is specially designed to trap bits of rotting flesh. This breeds several dozen varieties of bacteria including some of the most virulent and deadly bacteria on earth. Flesh eating necrotizing bacteria, blood-born bacteria causing sepsis, bacteria that knock out the immune system, an entire host of different nasties.

        One bite from a Komodo and it's saliva introduces all of these infections at once. A bite victim almost inevitably dies within one to three days. No known antibiotic can cure an established infection.

        The exciting part of the story is that Komodo Dragons obviously must have evolved an amazingly powerful defense to all of these bacteria. An expedition was sent to collect some Komodo blood and work is ongoing. They have isolated multiple anti-bacterial compounds and hopefully they will be able to make incredibly powerful new antibiotics available in a few years.

        -
        • They have isolated multiple anti-bacterial compounds and hopefully they will be able to make incredibly powerful new antibiotics available in a few years.

          Yeah, but some incredibly powerful antibiotic that a Komodo dragon (Varanus komodoensis) can handle may be quite deadly to us humans... Komodo dragons aren't all that closely related to us, you know (for one, they're cold-blooded).

      • Re:Dangerous? (Score:3, Insightful)

        by Urkki ( 668283 )
        • I've read a couple of articles on the semi-exception that the top predator on the planet (Homo sap) seems to be a partial exception. This is generally explained as an artifact of our recent conversion to predation. We do have some predator adaptations, but we haven't had time to evolve them fully.

        There's a much more simple explanation.

        Our immune systems are poor because they don't get enough stimuli when we are in childhood. Modern medicine takes care of most of our illnesses so our own immune system d

      • Re:Dangerous? (Score:3, Interesting)

        by mrogers ( 85392 )
        ...studies of wild chimp populations haved turned up data showing that they actually do get a significant part of their protein by eating small animals. So our predatory ancestry probably goes back at least 5 million years.

        That estimate is based on the false assumption that any trait present in modern chimps was also present in the common ancestor of chimps and humans. Chimps have evolved as much in the last 5 million years as we have. They may have discovered hunting as recently as we did - it's even pos

      • 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 i
      • I've read a couple of articles on the semi-exception that the top predator on the planet (Homo sap) seems to be a partial exception. This is generally explained as an artifact of our recent conversion to predation.

        It might also be explained by the fact that, alone (AFAIK) among the predators/omnivores, humans cook most of the meat that they eat. Cooking effectively kills most food-borne pathogens. This would go a long way toward preventing food-borne illnesses, and might explain the relatively poor defe
    • As I recall, the City of Cologne had actually introduced a wolf population into one of its parks to try and stem the burgeoning rabbit population there.

  • Pure FUD (Score:5, Informative)

    by Drakin ( 415182 ) on Friday December 26, 2003 @10:27AM (#7812368)
    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."



    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.

    • Seems to me pretty clear: the sick animals are going to be more easily caught by the wolves long before they're at the falling down, massive amounts of whatever it is causing the disease in their body stage. Which should reduce the risk to the wolves, eh?

      As for not figuring out how it's transmitted, that's kinda worrisome, don't you think? This disease is hitting herds of animals and even after a few years of observation we can't tell how it's transmitted?

      • As for not figuring out how it's transmitted, that's kinda worrisome, don't you think? This disease is hitting herds of animals and even after a few years of observation we can't tell how it's transmitted?

        What are you talking about? Your parent poster told you how it's transmitted: the deer are injecting each other's brains directly with syringes.
    • Safe enough, though it'll hardly make a dent in the disease. CWD is NOT a virus, it's a hell of a lot worse little bugger. There's really only two ways to counteract the disease, and neither gives warm fuzzies to self-labeled environmentalists.

      1-Kill the potential carriers. ALL of them, as many as can be found, reducing populations so drastically that it'll take 30-40 years for numbers to come back up, giving plenty of time for the disease to run its course in the one or two surviving carriers. Naturally,

      • Re:Pure FUD (Score:3, Interesting)

        by Fnkmaster ( 89084 ) *
        IANACROPS (I Am Not A Cancer Researcher Or Prion Scientist), but I strongly disagree that curing prionic diseases is on par with curing cancer. Cancer consists of a large variety of possible cellular mutations in growth control, protective and other signalling mechanisms. Curing it requires complete mastery of cellular signalling and control mechanisms taking into account all possible genetic variations in the affected person or animal, AND all the possible mutation sites that can lead to cancer.

        Curing

    • 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.

      Had the parent RTFA, they'd have read that CWD has not been found in areas near wolves, and that's why nobody knows what's going to happen. To quote:

      No one has been able to study whether wolves single out CWD-infected animals because the range of predator and disease have never overlapped.

      • Which is bullshit. We've got some CWD infections here where I live. This is a cause for great concern, because we also have a large number of elk ranches, and a respectable amount of white tail and mule deer.

        And guess what? We've also go wolves, who are well known to feed on the local elk.

        While I know that in the area talked about in the article the wolves have not interacted with the deer and elk, but there's other places where they have, in places where the wolf population hasn't been wiped out.
        • Elk ranches? Here's the problem: CWD is found in the wild less often than it is in captive populations. The ranches are fenced so that the animals (good jumpers) can't get out, and so poachers and wolves can't get in. Wolves aren't going to interact with CWD in captive populations, only with CWD in wild populations. Here's a map of CWD [cwd-info.org]. The wolves haven't made it down past Yellowstone, so they haven't encountered the wild CWD spreading north yet. Looking at the wolf populations in the Great Lakes are [timberwolf...mation.org]

  • Brain tissue? (Score:3, Interesting)

    by Johnny Mnemonic ( 176043 ) <mdinsmore@@@gmail...com> on Friday December 26, 2003 @11:17AM (#7812623) Homepage Journal

    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?
    • Very good question. I just found this link [surviveoutdoors.com] which seems to indicate they think spread is either maternal (before birth or through mother's milk I guess), or "lateral", I guess meaning from other deers, and they cite saliva as a vector.

      Presumably this means it's substantially more transmissible than Mad Cow Disease because it accumulates in other tissues outside of the brain and central nervous system. Or it means they are lying to us about the possible transmission vectors for Mad Cow Disease and that BS


      • Or it means they are lying to us about the possible transmission vectors for Mad Cow Disease and that BSE can possibly be transmitted through vectors besides brain tissue.

        That's exactly what I'm worried about as well. And from your link:

        We know that Mad Cow Disease can be transmitted to humans. Chornic Wasting Disease is similar to Mad Cow Disease; however, there has been NO documented evidence to date that it can be transmitted to humans by ingestion of infected meat.

        That unfortunately makes it as

        • Re:Brain tissue? (Score:2, Interesting)

          by Smitedogg ( 527493 )

          I live in Colorado, in an area were there are a lot of Elk Ranches (Yes, they do exist). CWD is covered fairly regularly by the local papers when they don't have enough fluff to fill the space

          Basically, no one has caught CWD as far as they can tell, yet. They really have no clue if it's possible, but there are a few cases here in Colorado where people have gotten Creutzfeldt-Jakob disease and have eaten wild elk. CJ disease is what humans get from mad cow. It is of course possible they got it from some ot

    • ... is how researchers have propagated the disease. In fact, the transmission means is unknown in part because we don't yet know the agent (as explained here [howstuffworks.com]). So, as in so many things, that the wolves might get and propagate the disease is just wild-assed FUD.

    • do deer etc in fact eat the brains of their own dead?
      --
      Cthulhu

      I think we may have just figured out is triggering the outbreak.

      -

    • What mystery (Score:3, Interesting)

      by Camel Pilot ( 78781 )
      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 cont
    • 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?

      The stuff is persistent. It can stick around on surfaces for a long time. And it survives harsh environments. Surgical implements remain infective for prion diseases even after being autoclaved and sterilized with heat and chemicals.

      Scrapie, for example, is a prion disease of sheep. Farms in Iceland that had not had any sheep present at all for thr
  • 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
    • First I would like to state that IANAB (I am not a biologist). That said, from what I have gathered CWD is a form of transmissible spongiform encephalopathies (which include mad cow diesease). Diseases such as these result in the formation of lesions on the brain via deformed prions. As a result of this, animals motor skills are impared. Learn more here [usgs.gov] and here [cwd-info.org]
    • "Wasting disease makes its victims distracted and unwary as it eats tiny holes in their brains, the Denver Post reported"

      I think that clears that up.
    • To quote from the Chronic Wasting Disease Foundation [slashdot.org] website:

      Chronic Wasting Disease (CWD) is a transmissible neurological disease of deer and elk that produces small lesions in brains of infected animals. It is characterized by loss of body condition, behavioral abnormalities and death. CWD is classified as a transmissible spongiform encephalopathy (TSE), and is similar to mad cow disease in cattle and scrapie in sheep.

    • Was with you all the way up to:

      Wolves (and other predators) will benefit until the deer are brought into a more sane population - then they'll turn on people.

      Has somebody been reading too much Little Red Riding Hood? Wolves pose little to no danger to humans and if given the opportunity and not harassed will go out of their way to avoid us. The vast majority of wildlife encounters result from people hiking and camping doing stupid things like feeding wild animals, leaving out food, toothpaste, human w
  • Whoever posted this is an idiot.

    Fact: Any Predator will zero in on weak prey.
    Fact: Wolves are not particularly dangerous to humans.
    Fact: Wolves have been exposed to more mind altering diseases than CWD, ie. Rabies for much longer than we have even known about CWD, much less tracked it.
    Fact: CWD does not cause the animals to go "MAD" or attack others.


    David Mech, a biologist with the U.S. Geologic Survey and a wolf expert, cautioned that until wolves and wasting disease actually interact, theori

    • Fact: Any Predator will zero in on weak prey.

      When did I say anything to the contrary? Did you actually read my synopsis?

      Fact: Wolves are not particularly dangerous to humans.

      And neither are black bears, mountain lions, and many other predators indigenous to this continent. What's your point? Would you walk up to them and pet them? They're still dangerous none the less.

      Fact: Wolves have been exposed to more mind altering diseases than CWD, ie. Rabies for much longer than we have even known about

      • from species to specious

        Should be "from species to species".

      • 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.

        My point is that the above phrasing was incredibly sensational. It implies that suddenly we will have packs of "mad wolves" ravaging the countryside.

        As you already stated wolves are no more "dangerous" than the black bears, mountain lions, and many other predators indigenous to this continent. What's your point?

        • My point is that the above phrasing was incredibly sensational. It implies that suddenly we will have packs of "mad wolves" ravaging the countryside.

          As you already stated wolves are no more "dangerous" than the black bears, mountain lions, and many other predators indigenous to this continent. What's your point?

          That perhaps repopulating wolves for the sole purpose of exposing them to this neurodegenerative disease will have some unfortunate consequences. The article never addressed the possibility that

  • Wolves as Dangerous Predators (Score:4, Insightful)

    by Snowspinner ( 627098 ) <philsand@3.14ufl.edu minus pi> on Friday December 26, 2003 @11:40AM (#7812796) Homepage
    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.

    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 /. 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.
    • Hear, hear! I also recommend reading Farley Mowatt's "Never Cry Wolf." Don't hold against it that it was made into a Disney movie, please. Farley Mowatt was sent into a section of Northern wilderness by the Canadian government to investigate the "wolf problem," as hunters were complaining to the government about the scarcity of Caribou, and how the wolves were killing them all.

      His findings, in short: Human beings were responsible for the enormous drop in Caribou numbers by indiscriminate hunting. The n

    • Wow. I never suggested that wolves were extremely dangerous, baby-eating monsters that needed to be eradicated. I used one word, "dangerous," to accurately describe an animal that can hurt humans, as opposed to, say, a Caribou or a Pronghorn or a Squirrel.

      You suggest that a mad wolf disease would not really result in unusually violent behavior, but this is not the case in other animals. Animals suffering from some kind of spongiform encephalopathy often undergo dramatic changes in their personality and di

  • Mad cow book (Score:1, Informative)

    by Anonymous Coward
    The book Mad Cow USA [prwatch.org] is now a free download (PDF) [prwatch.org]. It's the entire book with 245 pages.
  • > 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."

    Dogs (including wolves), horses, and rabbits
    are notably resistant to TSE prion diseases.
    Nobody knows why, yet.
  • up here in Idaho, farmers and herders generally hate wolves. they'd hunt wolves into extinction if it were up to them.

    this is one of the arguments in favor of the 7 main Idaho packs and numerous Yellowstone packs that could protect them.

    there are also a lot of hunters here that would rather have untainted game. letting the packs run wild, as they should be, could very well help hunting in this state, rather than hurt it as the farmers would have you believe.

    (sadly enough, the farmers' 3 main arguments
  • 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."

    Experience suggests that they will probably do something like launch a series of groundless IP lawsuits against the open source community.

  • A friend of my married into a rich family that owned a good sized island (somewhere in the NE us, won't be more specific).

    The deer and rodents were completely out of control. IT was great for deer hunting, but everyone in the family contracted Lyme disease. The ticks there were unbelievable.

    Then the western coyote made to that region of the country and swam to the island (an impressive feat). In one season they reduced the deer herd to a manageable size and then turned to the voles and other small rode
  • ...when I read:

    "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."

    was.. WEREWOLVES! Run for the hills! ;)

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