Researchers at University College in Dublin have found that supplementing the diet of cows with omega-3 fatty acid in the form of fish oil helps their heart and circulatory system, resulting in improved meat quality and a reduction in the amount of methane belched by the cows.

This lowering of emissions is important for the environment, as methane given off by farm animals is a major contribution to greenhouse gas levels. Worldwide there are 1.5 billion cattle and their collective belching is thought to account for 5 per cent of all greenhouse gas emissions.