Roo farts experiment has serious side

Researchers have spent months capturing kangaroo farts and while it sounds funny, there's a serious scientific pursuit behind their mad work.

Aussie biologist Adam Munn gets very excited when he recounts the months he and his colleagues spent capturing kangaroo farts.

It sounds like a dangerous pursuit.

And just why anyone would want to is baffling on the surface.

But this myth-busting experiment - which is not as perilous as it seems - has yielded important findings that will inform efforts to fight climate change.

It's long been known that kangaroos - unlike sheep and cattle - produce little of the potent greenhouse gas methane.

For some time, researchers intent on breeding less windy flocks and herds hypothesised that roos might have unique mix of micro-organisms in their stomachs that produce less of the gas.

The hope was that by transplanting these micro-organisms, cattle and sheep might produce less methane.

But Dr Munn's findings suggest otherwise and should help refocus sheep and cattle research on alternatives that might yield results.

The experiment saw captive but content red and western grey kangaroos kept in comfy, sealed chambers, allowing researchers to analyse to mix of gases going in, and those coming out.

"We think that the methane is low because of the way food moves through the kangaroo stomach, and not because of a unique gut fauna," he tells AAP.

The battle for less windy livestock is a serious issue when it comes to climate change.

In the year to March 2015, agriculture accounted for 15 per cent of Australia's greenhouse gas emissions. And the agricultural sector is the nation's dominant source for methane.

Dr Munn says more research needs to be done to work out the contribution various species make to greenhouse gas emissions.

He says that information will be valuable to Australian farmers in the future, under any carbon pricing or credit system.

"We need to understand where do the ruminants sit, compared to other wildlife that aren't heavily domesticated for production systems," he says.

"If we know that, there may be, for example, some benefit for land managers to having a lower density of (methane) intensive animals, and having mixed species grazing, instead of single species grazing."

The research is the work of Dr Munn, from the University of Wollongong, Professor Marcus Clauss from the University of Zurich, and PhD student and vet Catharina Vendl.

It was carried out at UNSW Fowlers Gap Arid Zone Research Station in far western NSW, and the findings have been published in The Journal of Experimental Biology.