Reducing methane emissions from livestock may be a step closer thanks to the discovery of a previously unknown bacteria from the gut of a wallaby.

Sheep, cattle and wallabies all produce methane while digesting plant material, and release the gas build-up by belching.

For some time, scientists have known that tammar wallabies produce only one-fifth of the amount of methane compared to cows and sheep.

Professor Mark Morrison from the CSIRO's division of livestock industry says the answer lies in the wallabies' digestive system.

"We started to discover that there were several types of bacteria that we really hadn't seen before," he said.

"Perhaps the genetic information that we'd recovered... could help us work out a way to go back to the laboratory and actually grow these bacteria for the first time, and that's actually what we did."

The study, published in the journal Science, used a process called metagenomics to take a very close look at what kind of bacteria live in a wallaby's stomach.

Although these bacteria were new to science, they have close relatives in livestock.

Professor Morrison hopes that by encouraging their growth, it will be possible for livestock to produce less methane.

"Our goal is to look for the same sorts of micro-organisms that we believe are already present in cattle and sheep, and find a way to increase their numbers and also their contribution to the digestion process," he said.

Professor Morrison says lower methane means more that just environmentally friendly livestock.

"The inventories that are being done in Australia would suggest that the emissions from livestock represent about 12 per cent of our total greenhouse gas emissions," he said.

"But just as importantly is that the efficiency of the livestock industry is compromised by the fact that this methane gas is being produced.

"So if we can find a way to redirect those feed-based ingredients back towards products that the animals can use for their own growth, rather than having it released into the environment as a form of gas, it should improve the efficiency of livestock production and also help with the sustainability of that enterprise and its profitability."

Professor Morrison says it means healthier livestock as well.

"Absolutely. I think that this really has to be thought of as a sort of win-win situation," he said.

Other experts says this is a promising avenue of research.

Dr Adam Munn, from the Institute of Conservation Biology and Environmental Management at the University of Wollongong, says scientists have only studied a handful of kangaroo or wallaby species in this manner.

He says there may be other species that release even less methane than the tammar wallaby.

"The study used a really novel technique to find out what the bacteria might have been in the tammar wallaby," he said.

"But they also noticed that the signal for that bacteria wasn't as strong in another species, the western grey kangaroo [for example].

"So I think what that suggests is there may be other marsupials out there, and other kangaroos in particular, that may be even more efficient and even more low-methane emitting, and it's worth looking at the other species."