Greenhouse gas methane may get the boot by kangaroos

By William Atkins
Friday, 07 December 2007 19:03

Science - Climate

Australian scientists have found that kangaroos have a special bacterium in their stomachs that doesn’t contain methane. They are trying to identify this bacterium and then develop a way to itransfer it to other animals, such as cattle, pigs, and sheep, which emit large quantities of the harmful greenhouse gas.         

Methane is one of the greenhouse gases that has been implicated in the warming of the planet, what is called global warming. Carbon dioxide and nitrous oxide are two other greenhouse gases.

Inside the stomach, fermentation happens. Hydrogen is mixed with food and bacteria, which eventually is turned into methane as a byproduct. And, it is ejected into the atmosphere whenever animals, like humans and cows, flatulate. At least, in many animals this methane is produced. It isn't produced in kangaroos.

These researchers have studied the digestive system of cattle, along with kangaroos, for about four years. They estimate that the average cow produces about 66 gallons (250 liters) of methane each day. Somehow, kangarees are able to eat the grass and plants native to Australia and not produce methane in the process, unlike European livestock, which produce methane from the grasses and plants they eat.

Senior research scientist Athol Klieve, from the Queensland state government, states in the Telegraph.co.uk.com article “Kangaroo bacteria could fight climate change”, "Rather than produce methane, kangaroos produce acetate which aids digestion."

Because of this special bacterium, which is generally called digestive flora, in the digestive tracts of kangaroos, they produce flatulence that doesn’t contain methane, but instead produces acetate. If they can develop a way to input this bacterium into the stomachs of cattle, sheep, and other domesticated animals, they could help to reduce the amount of methane that gets into the atmosphere.

Klieve, stated, within the AFP article “Eco-friendly kangaroo farts could help global warming: scientists”, "Fourteen percent of emissions from all sources in Australia is from enteric methane from cattle and sheep.”

The more agriculturally inclined a country is, on the whole, the more methane is produced from animals. And, the more industrially based a country is, the more carbon dioxide is usually emitted from manufacturing facilities.

These researchers also say that this special bacterium makes the digestive process more efficient (about 10 to 15% more energy is produced from the same amount of feed) and could theoretically save millions of dollars in feed costs for farmers and ranchers. So far, the researchers are studying about forty different types of bacteria, hoping they can isolate the ones (or one) that causes methane not to be produced inside the stomach.

Researchers say that it will take at least three more years to isolate the bacterium before it can be transferred to other animals.

An informative article on the research going on in this area is found in the Landline article “Something in the air”.