The project aims to breed more efficient cows that convert their food into more milk and less methane, one of the greenhouse gases blamed for rising temperatures across the planet.

"We're looking at feed conversion efficiency," said Dieter Adam, a manager at New Zealand's Livestock Improvement Corporation. "We want fuel-efficient cows."

The Australia-New Zealand Biotechnology Partnership Fund said the research project would help farmers selectivly breed cows that with were more efficient in converting food into milk.

"There is some scientific evidence indicating that if cows are more efficient milk producers, they produce less methane," Adam said.

In 2003, the New Zealand government attempted to impose a methane tax on farmers because their livestock was responsible for more than half the country's greenhouse gas emissions.

But the so-called "fart tax" was dropped after protests from farmers.