8 July 2010 Last updated at 05:20 ET

Burp O-Meter used on cow belches on Merseyside

Cows release methane when they belch

Belching from cows on Merseyside is being monitored by a "Burp O-Meter" to measure the methane being released.

The research, by the University of Liverpool and Tesco, is being done to see if farmers can improve their animals' etiquette.

The Burp O-Meter, a laser technology device, will record the potency of burps from cows on different farms over six weeks.

Climate experts believe methane accelerates global warming.

Researchers from the University of Liverpool position the hand-held laser methane device 3m from the cow's mouth for five minutes to record the burp and level of methane exhaled.

This is carried out four times a day over 24 hours to study the variation on each farm and see if this is related to when and how cows are fed.

'Ongoing challenge'

Ten dairy farms that supply Tesco are involved with 100 cows taking part.

Dr Rob Smith, University of Liverpool, who is leading the research, said it was a misconception that cows released methane from their bottoms.

"Horses and humans release methane from their rears, but cows actually belch it out.

"We are trying to understand what goes on in their gut and how we can best change our farming style to reduce the amount of methane the cows produce.

"By changing the way we farm we can get a quick reductions to the carbon footprint on your milk bottle."

Tesco dairy agriculture manager Emma Jones said: "Methane is around 20 times more powerful than carbon dioxide and is an area where significant improvements have already been made, due to improved yield and health.

"I look forward to seeing how we can use the results to the benefit of our farmers and the wider dairy industry."

Tesco dairy farmer and joint-chair of the Tesco dairy environmental working group, Mark Lovatt, added: "Reducing the amount of methane gas caused by our cattle herds is an ongoing challenge for dairy farmers.

"Although windy cows may raise a smile, it is a serious issue and this kind of research is essential."