Nutritional strategies to mitigate greenhouse gases emission from livestock agriculture: a review

Received: 11/11/2013 Revised: 13/12/2013 Accepted: 15/12/2013 Abstract Methane is the second key greenhouse gas (GHG) and enteric fermentation in livestock is one of the largest sources of methane emission, producing 15-20 % of the total anthropogenic methane. Methane production by enteric fermentation in the rumen accounts for the 2-12% loss of gross energy and consequently influence performance of ruminants. In addition, increases in methane emission from livestock leads to environmental pollution and global warming. Therefore, livestock industry strives for efficient strategies to reduce emission of methane from enteric fermentation. Animal nutritionists are working for finding out strategies to reduce the GHG from ruminant by dietary manipulation. Dietary inclusion of feed additives like organic acids, prebiotics, nitrates and sulphates, plant secondary metabolites (PSM) like essential oils, tannins and saponins results into considerable reduction in methane production. Therefore, the aim of this paper is to review current knowledge on rumen methanogenesis and special emphasis on nutritional approaches to reduction methane emission from ruminants.