Sunday, April 12, 2009

I’m Not a Vegetarian But…

Once in a blue moon I buy a little piece of round steak to slice up and throw into a stir fry. So the other day I was browsing the meat section, and noticed on a package of beef the claim that, “our cows are 100% vegetarian!”
It stopped me cold. Wait a minute. Aren’t all cows vegetarian? All the ones I knew back when I grew up on the farm certainly were.
Then I remembered mad cow disease (Bovine Spongiform Encephalopathy, or BSE). The main way it spreads is by feeding cows to other cows. No, a cow doesn’t step up to a steak dinner and think, “Elsie, is that you?” What happens is that sick cows, sheep, and chickens are butchered, ground up, and mixed into cattle feed.
Aside from my gut reaction, “What a stupid idea,” my curiosity was piqued, and I did a little reading, and learned about the warble fly, and prions, among other things.
Turns out that a couple of decades ago the British government required cattle owners to use an aggressive organophosphate to kill off the warble fly (hypoderma bovis). OK, this is where it gets really creepy: the warble fly lays its eggs on the front legs of the cow. The cow licks its legs, ingesting the eggs. Once the eggs are inside the cow they hatch into larva which then tunnel through the cow’s body until they are just under the cow’s skin, where they cause bumps, or warbles. When the warble flies are mature they break through the cow’s skin and fly away. Argh. Didn’t I see that story on Twilight Zone back in the 60s?
Anyway – the tunnels made by the larva fill with something called butcher’s jelly, making the meat unsaleable, and the holes left in the skin by the warble flies breaking through render the hide unusable. So the British government decreed that all cows should be treated to kill warble flies, using an organophosphate (poison) that was put on the cow’s back and went through the cow’s skin and spread through the cow’s whole system. Voila, no more warble flies, or other parasites. The meat and hides are fine. Everyone’s happy.
But wait. Now the prions in the cow’s body have been weakened by the organophosphate poison. What’s a prion (pree-on)? One definition I found says, “the theoretical unit of infection.” So, theoretically, a prion is a tiny little protein thing that is like a virus, but not a virus, and unlike a virus, it is not alive. This is where the research loses me. How can a tiny little part of a living body not be alive? OK, I’ll leave it for now. This is thick enough without following that particular garden path.
Suffice it to say that damaged prions are proteins that are folded wrong, making them infectious agents. Infection leads to the formation of amyloid plaques, which cause deterioration of the brain. That’s the short version.
Because prions are not alive they cannot be killed, or cured. They just go about their amoral business for amoral reasons of their own – and they aren’t talking – and when a cow or sheep that has these misfolded prions is ground up and fed to other cows, the prions are spread around and carry on with their plaque-making. When infected cows are butchered and fed to humans, the humans then have prions misfolding proteins in their bodies and plaques begin to form in their brains. The condition is untreatable and always fatal.
Whew. Suddenly I’m thinking that a 100% vegetarian cow is a good idea, and I’m wondering if the systemic flea poison I apply to my dog’s back is a bad idea. So I read up on that. Turns out that the active ingredient in that poison is imidacloprid, a “chlorinated analog of nicotine.” “Imidacloprid is notable for its relatively low toxicity to most animals other than insects,” according to Wikipedia. So, not an organophosphate, and much easier than getting fleas to actually smoke and die from that, although I’m sure that there is a strong contingent of people who would be happy to explain why you should never use imidacloprid.
So that’s our lesson for today, kids. Oh yeah, I also learned that there is a British punk/folk/rock band named Warble Fly. Maybe “The Brain Rotting Prions” was already taken.

1 comment:

The Crow said...

Great post, Mary! You're back in excellent form. Enjoyed this post very much.