Proposals to tax the flatulence of cows and other livestock have been denounced by farming groups in the Irish Republic and Denmark.

A cow tax of €13 per animal has been mooted in Ireland, while Denmark is discussing a levy as high as €80 per cow to offset the potential penalties each country faces from European Union legislation aimed at combating global warming.

The proposed levies are opposed vigorously by farming groups. The Irish Farmers' Association said that the cattle industry would move to South America to avoid EU taxes.

Livestock contribute 18 per cent of the greenhouse gases believed to cause global warming, according to the UN Food and Agriculture Organisation. The Danish Tax Commission estimates that a cow will emit four tonnes of methane a year in burps and flatulence, compared with 2.7 tonnes of carbon dioxide for an average car.

Agriculture, transport and housing are not included in the EU's Emissions Trading Scheme (ETS), which enables industrial companies to buy and sell permits to emit carbon dioxide. Instead, EU member states are obliged to cut the emissions from non-ETS sectors by 10 per cent overall by 2020.

While Romania and Bulgaria will be allowed to increase emissions, Ireland and Denmark are each faced with cuts of 20 per cent in farming sector emissions.

The cow tax proposals would raise funds to buy allowances from other member states or to invest in technology that might reduce emissions. Denmark is believed to be further advanced with housing for pigs that captures and stores methane emitted from the animals. The gas can be used as a fuel for power generation.

A spokesman for the European Commission said that a cow tax was not its preferred option. “We would rather have solutions that reduce emissions by capturing methane from manure and new animal feeds that reduce methane.”

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