Scientists close in on eco-friendly sheep

Scientists have moved a step closer to developing a breed of sheep that belches less methane as part of a quest to reduce greenhouse gas emissions, New Zealand researchers say.

A study by scientists from New Zealand's AgResearch institute and the US Department of Energy's Joint Genome Institute, published in the journal Genome Research, discovered microbial differences in sheep that have high or low methane emissions.

"The study used the large sequencing and data analysis capabilities of the Joint Genome Institute to look at the occurrence, abundance and expression of methanogen genes between low and high methane-emitting sheep identified from flocks in New Zealand," said AgResearch scientist and project leader Dr Graeme Attwood.

Methane is produced in a part of the stomach called the rumen, by microbes called methanogens.

The release of methane gas from New Zealand's 30 million sheep, as well as emissions from cattle, account for almost one third of the country's greenhouse gas emissions.

The differences revealed by the international team may help define the methane trait in sheep and assist in the selection of low-methane flocks in future.

The study is part of a programme that aims to breed sheep for New Zealand farms which are low methane-emitters but maintain their ability to reproduce, as well as retaining or improving their meat and wool production.