Australia works to reduce sheep burps

Australian scientists are working to breed a sheep that belches less, as they look for ways to reduce harmful methane emissions from the country's woolly flocks.

12% of Australia's total greenhouse gas emissions originate with agriculture, and some 70% of that amount is blamed on ruminant livestock, with most of it coming from burps, research scientist John Goopy said today.

With sheep, almost all of the methane produced comes out of their mouths.

Scientists from the New South Wales Department of Industry and Investment are measuring the sheep's methane emissions by herding them into a specially designed booth shortly after they eat and then calculating the amount of gas belched.

They hope to find whether there is a genetic link between the sheep that produce the least methane, which could then be exploited to breed low-emissions sheep.

Of the 200 sheep so far tested, about half produced much more than average while the other half belched considerably less methane.

'The biggest single determinant of methane production in cattle and sheep is the amount of feed they eat. But even once that is taken into account, I have found significant differences between individual animals,' Goopy said.

The scientist said methane has about 17 times the environmental warming capacity of carbon dioxide, a greenhouse gas blamed for global warming.

He said if the methane produced by Australia's 80 million or so sheep was reduced by just 10% or 15% in the next decade, it would have 'a substantial and also a long-term impact on our greenhouse gas emissions'.