23 September 2004David Adam
Scientists have developed a jab to stop sheep belches and farts from damaging the environment.
Wind from sheep, cows and other farm animals accounts for about 20% of global emissions of methane - a greenhouse gas 23 times more potent, volume for volume, than carbon dioxide.
Now a team led by André-Denis Wright of the Commonwealth Scientific and Industrial Research Organisation in Perth, Australia, has devised a vaccine against the microbes that produce methane in sheep rumens.
After two injections, sheep burped out 8% less methane in a 13-hour test in a closed chamber. The results appear in the journal Vaccine.
The vaccine was effective against 20% of the bugs inside the 20 sheep used in the trial. Scientists are now working to increase this and to cut methane production further. Emissions from farm animals are a particular problem in Australia and New Zealand, where they account for up to 80% of methane produced.
Researchers in Britain and other countries have experimented with changing composition of feed to make intensively farmed animals produce less methane. A vaccine would be more useful because it could be given to all ruminants.
