Fish oils fed to flatulent cows could reduce greenhouse gas emissions

Omega 3 fatty acids in fish oils have many documented benefits to humans including the reduction of cholesterol, but what of the benefits to animals and the environment in general? While assisting the heart and circulatory system in animals and improving the meat quality in cattle, it is also, according to researchers at the University College in Dublin, beneficial in reducing methane levels from flatulence when added to the diet of cattle.

Methane given off by farm animals is a major contributing factor to greenhouse gas levels emanating from the agricultural sector, prompting researchers at the University College in Dublin to conduct a study into adding fish oil to the feed of cattle. They have reported that by including 2% fish oil into the diet, a reduction in the amount of methane released by cattle through flatulence was achieved.

With over a third of all methane related emissions (amounting to 900 billion tonnes per year) attributed to methanogen bacteria that live in the digestive systems of cattle, sheep and goats, flatulence in animals becomes a serious matter. When calculated in volume, methane is a potent greenhouse gas; 20 times more powerful at trapping solar energy than carbon dioxide. According to Dr Lorraine Lillis, fish oil affects the methane-producing bacteria in the rumen part of the cow’s gut, leading to reduced emissions. Approximately 50% of methane emissions in Ireland are attributed to farm animals, and with the country being one of the six main producers of beef and veal in the European Union (EU), an alternative to placing a cap on stock numbers (a scenario that is a possibility) to reduce methane emissions could only be an advantage to the primary producer and the environment. It is yet to be stated by the University of Dublin the exact amount of the reduction of the methane released, is this measurable?

Dr Lillis states that the aim of the research could bring about a more targeted approach to reducing methane emissions in animals by understanding which microbial species are influenced by changes in diet and relating them to methane production. If this study results in implementing a dietary change to cattle that is viable and shows proven, significant methane emission reduction, then this could be another battle won in the very extensive war to reduce greenhouse emissions.

Anne Hanrahan