Animal technicians and scientists from South America, Southeast Asia and New Zealand are in Palmerston North to get the latest information on measuring methane emissions from sheep and cattle.
The city is home to the Agricultural Greenhouse Gas Research Centre, and scientists say it has the largest research facility and data on animal emissions in the world.
Concern over greenhouse gas emissions comes because of their contribution to climate change. The scientists concentrate on methane as it is 24 times more potent than carbon dioxide.
Cesar Pinares-Patino, from Peru, says eight scientists, four from South America and four from Asia, are in Palmerston North to ensure methane readings are done uniformly around the world.
They are in the city until February 1.
The Greenhouse Gas Centre has 24 sheep and four cattle respiration chambers, which measure all the gas coming from the animals.
"The students here are working with the tracer system, it is more easy to check animals' methane emissions and most countries don't have respiration chambers," said Dr Pinares-Patino.
Northern Ireland beef research scientist Francis Lively said feed types had an impact on the greenhouse gas emissions from animals.
"It's a balancing act, better feed means an animal can go to slaughter earlier, but it also means more emissions. Poorer feed means they are on it for longer - but emissions are lower."
Dr Lively said the easy way to cut greenhouse gas emissions from animals would be to reduce their population, but the global population was growing and needed feeding. Therefore, mitigation of methane seemed the best way to combat emissions.
The global human population grew from about 5 billion in 1987 to 7 billion in 2011, and is expected to reach 9 billion people in 2050.
Dr Lively said about 96 per cent of methane from farmed animals came from their burps, with the remainder coming out the rear end.
About half New Zealand's greenhouse gas emissions come from farm animals.
- Manawatu Standard
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