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Reducing Enteric Methane for improving food security and livelihoods

What is enteric methane?

Naturally occurring methane is generated by anaerobic fermentation, where bacteria break down organic matter producing hydrogen (H2), carbon dioxide (CO2) and methane (CH4). This process naturally occurs in the digestive system of domesticated and wild ruminants, natural wetlands, and rice patties.

In ruminants, methane is produced mostly by enteric fermentation where microbes decompose and ferment plant materials, such as celluloses, fiber, starches, and sugars, in their digestive tract or rumen. Enteric methane is one by-product of this digestive process and is expelled by the animal through burping. While other by-products (acetate, propionate and butyrate) are absorbed by the animal and used as energy precursors to produce milk, meat and wool.

Enteric methane production is directly related to the level of intake, the type and quality of feed, the amount of energy consumed, animal size, growth rate, level of production, and environmental temperature. Between 2 to 12% of a ruminant’s energy intake is typically lost through the enteric fermentation process.