Greenhouse gas emissions from Ireland's dairy herd have dropped by almost 10 per cent as a result of a reduction in the number of dairy cows, the Agricultural Science Association conference in Sligo heard yesterday.
Prof Frank O'Mara, from UCD's School of Agriculture, Food Science and Veterinary Medicine, said that if the productivity of dairy cows continued to increase at the same level over the coming years, cow numbers would continue to drop, as would greenhouse gas emissions.
Emissions from agriculture were estimated to be 19 million tonnes a year, or about 30 per cent of total emissions. Methane from dairy and beef cattle accounted for 40 per cent of total agricultural emissions.
Prof O'Mara said that methane was produced by the animals during digestion, but high-fibre feeds such as grass or silage resulted in the greatest level of methane-production. Modifying the feed would reduce the emission levels.
He said Teagasc economists had projected a significant fall in beef cow numbers between now and 2012, as a result of changes in EU policy, and this would also have a significant impact.
"The overall drop in reducing dairy cow numbers forms a major plank of the Government's plan to bring overall emissions towards the target set in the Kyoto Protocol," he said. It was expected that emission levels would drop by almost 10 million tonnes between 2008 and 2012.