New Zealand researchers are curbing the country's greenhouse gas emissions one sheep fart at a time.

Scientists at Invermay Agricultural Centre in Mosgiel, about 360km south-west of Christchurch, have bred climate-friendly sheep that produce 10 per cent less methane than their gassy counterparts.

Livestock emissions are the biggest contributor to New Zealand's greenhouse gas emissions and make up about 10 per cent of Australia's total greenhouse emissions.

Breeding climate-friendly sheep

Dr Suzanne Rowe says her climate-friendly sheep could be a money saver if the industry was put under a carbon trading scheme. ( Supplied: AgResearch )

Agricultural research company AgResearch is behind the project, which is being led by senior scientist and quantitative geneticist Suzanne Rowe.

Now in its third generation, Dr Rowe said the breeding program began with two breeding lines of 100 ewes that were separated into high and low gas emitting groups.

"We were looking … to see whether the trait was genetic and what the effect of breeding for low methane was, and whether there was effect on other health and production traits," she said.

Dr Rowe said a lower-emitting sheep breed could prove useful if the agriculture industry found itself under a carbon trading scheme.

"If we chose an arbitrary carbon cost of $NZ100 per tonne, we'd be looking at a cost of around $NZ43 per ewe. It really starts to stack up," she said.

"We are hoping to provide — within the next 12 to 24 months — breeding values to the industry for methane.

"If someone is in a breeding scheme, not only do they get a breeding value for production traits, they also get a breeding value for methane."

Dr Rowe said sheep release most of their methane by burping, which her team measures by placing sheep in a sealed aluminium chamber for 40 minutes to an hour while the emissions accumulate.

Dr Rowe's research shows the lower-emitting trait is about 20 percent heritable and comes with some added bonuses.

"What we've seen carry along the way is higher wool growth. We also tend to see a leaner animal.

"We also see a lower rumen size. The lower emitting animal tends to eat smaller meals with more frequency than her higher-emission counterparts," she said.

During Dr Rowe's research, sheep spent time in a purpose-built 'fart chamber' officially referred to as an emissions accumulation chamber. ( Supplied: AgResearch )

Less wind equals more production

University of Western Australia (UWA) animal science professor, Philip Vercoe, said methane emissions were simply wasted energy.

"Of all the effort, time and labour that goes into providing feed for the animal, and all the time the animal puts in to finding and consuming that feed, something like 10 per cent of that is belched into the atmosphere," Dr Vercoe said.

"It is a greenhouse gas and a potent greenhouse gas, so if you can capture that energy and put it into something better then there's dual benefits."

These emission-reducing practices, including genetic selection, can lift productivity by up to 22 per cent and reduce methane emissions by up to 40 per cent, according to a 2015 report by Meat and Livestock Australia.

"Research indicates that up to 40 per cent or more of the feed energy lost in methane from livestock can be captured and put to productive purposes," the report read.

Annually, methane emissions from Australia's cattle and sheep equates to about 55 million tonnes of carbon dioxide equivalent.

Just last year, Australia's red meat industry set the goal of becoming carbon neutral by 2030.

Meat & Livestock Australia managing director, Richard Norton, said the 2030 goal was achievable with industry commitment, the right policy settings and new investment in research, development and adoption.

Similar work across the pond

From 2009–2012 the former Labor Government spent around $74 million funding several programs to assist in the reduction of livestock methane emissions.

Such programs included the National Livestock Methane Program and the Reducing Emissions from Livestock Research Program.

Dr Vercoe was involved with most of the emission reduction programs and said they each had a "three-pronged attack" to try and reduce emissions.

Dr Philip Vercoe says adding Eremophila to livestock feed can reduce gas emissions by 10–15 per cent. ( Supplied: University of Western Australia )

The first approach involved researchers applying a similar selective breeding program with cattle.

Another approach was to find a food source to reduce the amount of methane produced per kilogram of feed.

For example, Dr Vercoe said the addition of the native plant Eremophila to the ruminant diet resulted in a 10-15 per cent reduction of emissions.



"[A third approach] was actually trying to target the specific microbial community that sheep and cattle carry around in their rumen that are responsible for methane production."

Dr Vercoe said methane emissions could reduce by up to 40 per cent by using a combination of all three methods.

"We need to leave a legacy that is a positive one, that helps our industry generate all the feed that is required by a growing a global community, but we need to do it in a way that allows us to carry on into the future," he said.

However despite encouraging results, funding for flatulent-focused research programs has dried up, which Dr Vercoe said was disappointing.

"Scientists were pulled together towards a common goal because there was enough funding to enable people to be creative and take a multi-discipline approach to the problem," he said.

"When the money is withdrawn it makes it much more difficult to have collaborative multi-discipline programs.

"All of a sudden, all of that consortium splits up and goes it alone. It's one of the major issues we've got to address at a national level."