Sidebar by Martha Quillen
Agriculture – May 2004 – Colorado Central Magazine
We’d be remiss not to notice that Clint’s article once again brings up some controversies originally inspired by Hal Walter’s February column, A Regional Answer to the Food Supply Questions.
Jim Scanga, owner of Scanga meat, wrote a letter for our March edition challenging many of Hal’s contentions, among them: that corn fed animals are inferior in nutrition, taste or quality; that corn fed animals are more susceptible to mad cow disease than grass-fed animals; and that raising animals naturally always produces a better product. In fact, Scanga feels that many current claims for natural and organic products constitute “throwing science out the window.”
In the April issue, however, Slim Wolfe questioned Jim’s contentions: “…Scanga’s letter,” he wrote, “clouded the issue by mixing up Wasting Disease with Mad Cow, since the former affects game who are not fed on cow-parts.”
In Jim’s defense, we’d like to point out that corn-fed meat is not necessarily fed animal products either.
Furthermore, rules for animal feed have been significantly tightened in recent months, so all U.S. cattle are less likely to consume animal products than they were in the past (whether they are traditionally or organically grown).
But more to the point, it seems as if Colorado Central should address some of the questions that this debate has initiated.
First and foremost: Is there a connection between Chronic Wasting Disease (CWD) and Bovine Spongiform Encephalopathy (BSE)?
The answer: Both are Transmissible Spongiform Encephalopathies (TSEs), from a family of similar diseases, which are thought to be caused by abnormal prions (a type of protein which can become an infectious agent). But in actuality, the exact cause (or causes) of Mad Cow and Chronic Wasting disease is (or are) unknown.
British studies (interested readers can find the full text of the Phillips Inquiry and Horn Report on the internet) agreed that BSE spread rapidly in Great Britain because cattle feeds included meat by-products from infected cattle.
But to date, there is no general agreement on the origin of the disease. A leading theory contends that BSE developed because cattle were given feed containing sheep infected with scrapie. But many researchers disagree (because scrapie had been around for 300 years without infecting cows or people and there are notable dissimilarities in the abnormal prions found in scrapie and BSE).
Other scientists suggested that environmental factors may have made British cattle particularly susceptible to BSE, so labs have studied the effects of various substances (including pesticides, herbicides, toxic spills, organophosphates and artificial hormones, and some substances do seem to encourage the development of BSE).
But there’s no general agreement on why cattle started getting the disease in the first place. Though some researchers have theorized that a more communicable form of TSE may have been introduced by infected foreign animals in British zoos, that hypothesis has proven unlikely.
Although they’re related, TSEs don’t ordinarily cross species barriers easily. And that’s one of the reasons why authorities in the U.K. spent years insisting that the rise in Bovine Spongiform Encephalopathy didn’t pose a threat to humans. After all, they reasoned, scrapie had been around for hundreds of years and had never infected humans; thus humans were presumed to be immune to BSE, too.
But that turned out to be untrue.
And that takes us to CWD.
There have been no known cases of CWD infecting humans or domestic animals. And experiments have shown that even when the CWD pathogen is injected directly into the brains of cattle, only a few become ill. Furthermore, cattle living with infected deer did not become infected in four and a half years — even after ingesting infected brain material.
But that doesn’t mean that it couldn’t happen.
Nor does it mean that CWD couldn’t be transmitted to humans by other means. Thus, the Colorado Department of Public Health recommends that hunters refrain from taking animals that show abnormal behavior or are in poor condition. They also advise that hunters should wear latex gloves when field-dressing animals; should bone meat; and should avoid undue contact with the brain, eyes, spinal cord, lymph nodes, tonsils, and spleen of harvested animals; and should only consume the muscle meat.
Since CWD has been found in deer and elk in Colorado, and BSE has only been found in a dairy cow in Washington state, local venison is far more likely to come from a TSE-infected animal than beef.
But Mad Cow Disease tends to be more worrisome, since human illness has not been attributed to CWD.
For those who are apprehensive about Mad Cow Disease, however, the same advice can be applied. Even when meat comes from an infected animal, much of the risk can be alleviated by eating only deboned muscle meat and by avoiding brain and nerve tissue and the ground meats which may contain them.
Consumers should also note that TSEs are not eliminated with careful cleaning and thorough cooking. In fact, they have been spread from one person to another during surgery due to contaminated medical instruments which have been thoroughly cleaned and sterilized.
But Variant Creutzfeldt-Jakob Disease, (also known as Mad Cow), the ailment humans are believed to get from BSE-infected beef, is very rare. Although the United Kingdom experienced a BSE spread of epidemic proportions in the 1990s, with tens of thousands of cattle infected, as of January, 2004, there had been a mere 155 confirmed cases of variant CJD reported in humans world-wide. BSE is invariably fatal, however, and decidedly unpleasant, so drastic precautions may be reasonable despite the relative rarity of the disorder.
As for CWD, it appears to spread directly from animal to animal and by way of contaminated soil and surfaces, probably through contact with saliva, feces, and/or urine. So it’s out there, and it could spread. But similar diseases have been out there for hundreds of years without spreading.
So what should a sensible person do?
In truth, so little is known about prion diseases that it’s unclear. Like Jim Scanga, we tend to be a mite cynical about some of the claims made for natural foods. And since no one knows how BSE originated we certainly can’t guarantee that natural, organic cows are immune.
But clearly, the small, local operations, which Clint and Hal write about know where their animals come from and keep track of animal diets; they don’t use commercial feeds; and they don’t give their animals meat or meat by-products. So their products should be immeasurably safer than the downer cows that have recently made the news.
In this brave new world of prion disorders, however, there are few certainties. Meat from healthy animals could be contaminated with abnormal prions from other cattle during processing. Or organically produced cows could be infected by environmental contaminants.
After all, even though cattle are vegetarians, they’re not so fastidious that they don’t munch down insects, desiccated rodents, and/or animal tissue lurking in the grass they graze. And the Phillip’s inquiry conducted in the United Kingdom concluded that, “A cow can become infected with BSE as a result of eating an amount of infectious tissue as small as a peppercorn.”
On the other hand, however, the United Kingdom seems to be making great strides in its efforts against BSE, and the primary focus of those efforts has called for eliminating meat and meat-by-products from animal feeds.
Furthermore, at this point contaminated fruits, vegetables or water are far more likely to do you in than BSE or CWD. And E-coli and salmonella are far more probable threats to your health. So our advice is to take reasonable precautions and not worry unduly — but keep an eye on events.
Citizens in the U.K. didn’t worry very much when more and more cows started showing signs of BSE — any more than we worry excessively about the spread of CWD in deer and elk. In fact, the Brits didn’t worry very much until domestic cats started acting weird and dying. After all, their government kept telling them that their food was safe, and they believed it. But now we know better.
So deer and elk hunters should take every precaution, processing their game carefully and eating only muscle meats. And if there are more cases of BSE in the U.S., beef consumers might do well to consider similar precautions.
Therefore, we’re not going to tell you that eating deer or beef is perfectly safe — because we assume that you’ve already heard that from enough government officials, cattlemen, and beef industry spokesmen.
As we see it, the USDA may be right in concluding that recent precautions will safeguard American cattle from BSE. But it’s also possible that current regulations won’t prevent more cases. In which case, we may find out that natural beef really is far safer from BSE than traditionally produced meat. But the evidence is still out.
In the meantime, however, there is a bright side. Recent events have fueled an interest in organic meat and smaller agricultural operations, and that’s going to mean more alternatives for consumers and more opportunities for small, local producers. If you want your beef grass fed, corn fed, range fed, or organically fed, antibiotic free or pesticide pure, or if you want to support operations that reject toxins and herbicides, or if you believe in environmental rangeland management, you should be able to find more of what you’re looking for in the future.
For information on BSE, TSE, and CJD check www.cdc.gov. For a take on the matter which doesn’t necessarily applaud the U.S. response, check www.priondata.org.
–Martha Quillen
