Sunday, 28 October 2012

food for thought

When I was growing up in the 1950s, chicken was a luxury dish, to be eaten only on formal occasions such as wedding receptions. However, this situation began to change towards the end of the decade with the advent of factory farming, but this increased availability of chicken came at a price, a price that seemed inconsequential at the time but now has assumed critical proportions.

There are two problems: the huge energy input to light and heat the enormous sheds in which most chickens are reared nowadays; and the need to feed all these captive birds, which cannot forage for themselves. The two problems are closely related.

If we focus on the amount of energy that is needed to raise an individual chicken to a size where it can be eaten, it becomes apparent that the process is inefficient, because in addition to the parts of the chicken that can be eaten, energy has gone into producing feet, feathers, a head, blood and guts, which are essentially waste by-products. These can of course be reprocessed, but that requires yet more energy.

How would this reprocessing be achieved in nature? The animal kingdom divides neatly into two: herbivores eat plants, and carnivores eat the herbivores. But there is a third category, the detritivores, whose function is to clean up the mess left by the other two. Vultures and hyenas are part of this process, but by far the most important member of the clean-up brigade is the humble fly, without which the world would soon be buried under the weight of detritus generated by the twin processes of life and death.

However, it is not the adult fly that carries out this function but its larvae. Adult flies are justly reviled for spreading disease—they vomit on food and transfer contaminants from one food source to another—but this revulsion also extends to its infant offspring. Note that the larvae of butterflies and moths, widely acknowledged to be beautiful creatures, are called caterpillars, a name that has a romantic ring to it, even though the amount of damage they cause to food crops is often considerable. Fly larvae, on the other hand, are known as maggots, an altogether more sinister word and one that is often appropriated as a term of abuse. Yet once the large carrion eaters have had their fill, it is left to legions of maggots to scoff the rest before metamorphosing into more adult flies to carry on the cycle.

What if we could harness this process to deal with the waste from factory farms? This idea might sound far-fetched, but it is already being pioneered on a small but workable scale. The idea originated in South Africa, where chicken waste was routinely left in the open to rot. An astute observer noticed first the huge number of flies that this practice attracted and second the speed with which the waste disappeared.

Industrial trials involving millions of flies and tens of millions of maggots have shown that significant quantities of chicken waste can be consumed in just 72 hours. And this is where the feeding problem alluded to above enters the picture. Currently, chickens are fed fishmeal. Some of this is made from by-catch, unwanted fish species caught in the nets of trawlers fishing for other varieties. However, a lot of industrial-scale fishing, which itself requires huge energy inputs, is solely to produce fishmeal, and particularly worrying is a recent move to start fishing for the tiny crustaceans collectively known as krill to meet the demand from chicken farmers for fishmeal. In other words, having all but destroyed the top of the food chain in the world’s oceans, humans seem bent on destroying the bottom too. A better example of myopia would be hard to find.

However, the maggots that ate the chicken waste in the previous paragraph can be dried and processed into chicken feed that has been given the proprietary name ‘magmeal’. If current trials can be scaled up sufficiently, it should become unnecessary to continue to pillage the oceans in order to feed factory-bred chickens. There is just one tiny problem: would consumers knowingly eat chickens that have been fed on maggots, given their likely revulsion at such things? Well, chickens raised naturally routinely scratch about in the soil for worms and grubs, and this does not appear to deter those consumers who are willing to pay extra for organic chicken. And most people were happy enough to eat beef from cows fed processed sheep’s brains, until, that is, it became apparent that they ran a significant risk of contracting a new variant of Creutzfeldt-Jakob disease.

10 comments:

  1. Magmeal might be a viable solution to this problem. Hell, chickens eat worms and other bugs, so I don't see why anyone would really care if they ate maggots, too. It's a shame that the food industry is destroying the planet.

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    1. The problem is that factory-farmed chickens don’t have a chance to eat what comes naturally, and most consumers have only ever tasted chickens bought from supermarkets, so they might be squeamish if they thought that the chickens they were buying had been eating maggots. You’re right though Helena, the food industry has a lot to answer for, but then the purpose of a food company is to make profits for its shareholders, not to promote healthy eating.

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  2. Wow, what a wealth of information here. It is so amazing how the world works in a way. If you take away certain species, animals etc, things just start to slowly break down unless we can come up with a better idea. When I first read about 'magmeal' here, I must admit I did cringe but as I read further I then thought, you are right, chickens do naturally scratch around for these things anyway.

    I guess I won't be so heavy handed with the flies and spiders who usually end up dead once my eye has seen them. Loved this post.

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    1. Naturally reared chickens have more flavour too Rum, but try telling that to the person who jumps at their supermarket’s latest offer of two whole chickens for £5.

      My advice would be to swat the flies but lay off the spiders. I have a Victorian terraced house in the UK, and it’s full of hunting spiders. When my wife protests, I tell her that if there are so many spiders, they must be finding something to eat, so they are doing a job for me, and I leave them alone. Incidentally, they all seem to have their regular ‘beats’, and you can almost set your watch by the regularity with which they patrol them.

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  3. Dennis, it's fascinating to see how your mind works-a scientific mind. It seems an ironic cycle of events (but very much in accordance with nature)to feed the chickens the very thing that would feed on them in the case of their demise in order to raise them to be fed to us. It's a poetic as well as a practical solution.

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    1. I must admit that I didn’t consider the poetic aspect of this situation Marty, but you’re right: there is a delicious irony in feeding chickens the very things that would eat them if they were to die in natural circumstances.

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  4. Ah...thanks for that most informative info. .........i think.
    I mean I enjoyed the read but not the super graphic scenes in the theater of my mind.

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    1. Yes, gruesome isn’t it Angie. Yet these horrible creatures perform a useful function in nature. And Western doctors have started using maggots to treat otherwise ‘difficult’ wounds. They eat necrotic/gangrenous tissue while leaving healthy flesh alone, a practice that I understand originated with the Mongols at the time of Genghis Khan.

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  5. Replies
    1. It certainly makes sense Ana, but let’s see if it catches on.

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