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If you grew up in suburbia like me, you might
not have ever considered the fact that cows
are pretty gassy creatures.
Just ask the German farmer who in 2014 had
to deal with a slight exploding shed problem,
thanks to his dairy cattle’s burps.
Turns out the thing that exploded was methane–aka
the natural gas that you might use to cook
And Bessie over here, can belch up something
like 200 to 600 liters of the stuff every
Methane is a product of the crazy digestive
system cows have–with four, yea four, stomachs.
Stomach number one is called the rumen, and
it’s home to a microbe zoo.
From protozoans to archaeans, you can find
practically every major kind of life in there.
Cellulose, the carbohydrate that makes plants
tough and fibrous, is technically impossible
for the cow to digest on its own.
Which is why it needs the help of all those
little microbe friends.
Some of them take the cellulose and break
it down into less complex molecules that the
cows can then digest.
The microbes release hydrogen gas and carbon
dioxide as waste products.
That hydrogen gas, if it were allowed to build
up, could interfere with further digestion,
because it’s actually toxic to the microbes.
So another group of microbes called methanogens
take the hydrogen and react it with CO2 to
The breakdown of cellulose is more efficient
when methanogens snap up that H2 right away.
The cow can’t use the methane, so it just
burps it out.
Which means it loses up to 10% of the energy
present in whatever grass or plant stuff it
But it’s kinda amazing that it gets energy
from cellulose at all–thanks to that microbe
Improperly ventilated barns aside, the real
reason to be worried about cow burps is that
methane is a nasty greenhouse gas.
Over a period of 100 years, one kilogram of
methane could potentially warm the Earth about
28 times as much as a kilogram of CO2.
And cows, along with other livestock, emit
many many kilograms of methane from their
burps — about this many in 2007.
That’s enough to make up about 7% of ALL
greenhouse gases emitted by human activities.
The planet is paying a high price for our
burgers and shakes.
So what can we do to save us from ourselves?
There are a couple of options: either cut
down the amount of methane the cows produce
in the first place, or find a way to capture
and use it.
People are experimenting with adorable backpacks
to collect cows’ gassy emissions.
And while this strategy isn’t widespread
yet, enough methane has been collected to
power an experimental city bus or two.
But it’s probably more efficient to stop
the burps in the first place.
And scientists have tried pretty much everything,
with mixed results.
One approach has been to vaccinate the cows
against their own gut microbes, persuading
their immune system to straight up murder
Researchers have also supplemented cows’
feed with essential oils like garlic, peppermint,
and eucalyptus to aid their digestion.
And because the amount of methane a cow produces
seems to be inherited, some researchers are
on the hunt for a breeding fix, breathalyzing
cows to see who’s got the least methane
on their breath and sending the clean ones
off to have babies.
So there’s no shortage of creative solutions,
once we can actually put them into action.
Until then, enjoy your gassy half-pints and
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