Methane as a greenhouse gas. Methane contributes approximately 18% to the overall global warming effect. This has been recognised internationally and the Kyoto Protocol has global reductions for methane set at 5.2% below the 1990 level for the period 2008-2012. In the UK, the government has set even stricter reductions and is committed to reducing methane emissions to 12.5% below 1990 levels for the same period. 70% of global methane formation is due to man's activities, of which 60% is from agriculture and the remainder comes from landfills, coal mines and oil exploitation. Just under half of the agricultural contribution is from ruminants.

Development of an anti-methane feed ingredient. Researchers at the Rowett are in the final phase of developing a feed additive for ruminants that inhibits methane formation and improves feed efficiency, i.e gives greater production per unit of feed consumed. The most recent stages of product development have been funded by Scottish Enterprise under its Proof of Concept scheme and by the Genomia Seed Fund . Results of applied trials in lambs greatly exceeded expectations, with the result that development of the results into a viable product was indicated to be highly favourable. A patent is pending. The Rowett, through its commercial arm, Rowett Research Services, has entered into a 12-month commercial/economic evaluation agreement with one of the world's largest chemical companies.

The science behind the discovery. Methane production is the main pathway for the elimination of hydrogen in the rumen. There are two distinct populations in the rumen microbial community – those which produce hydrogen and those which use the hydrogen to form methane. Rather than targetting the methanogenic microbes, the Rowett approach has been to find a means of diverting the hydrogen away from the methanogens, by trapping it (metabolically) before the methanogens can use it. Fumaric acid is one of the possible trapping agents (see British Journal of Nutrition 94, 27-35, 2005). By adding a form of fumaric acid to the diet, lamb growth trials have shown that up to 70% inhibition of methane formation can be achieved. Such an inhibition gives rise to an improved feed efficiency of 10%, i.e. the lambs gain weight 10% faster for the same consumption of feed.

It is the precise form of the fumaric acid that is important. Feeding fumaric acid at inclusion rates sufficient to give significant decreases in methane formation causes pH problems in the rumen. The breakthrough is that Rowett scientists have found a slow-release mechanism which enables up to 10% of the diet to be composed of fumaric acid without causing any problems of inappetance or digestive dysfunction.

Contact: Dr John Wallace 01224 716656

Media enquiries: Sue Bird 01224 716668, 07711 093417

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