Current Status and Mitigation Strategies of Livestock-Derived Methane Emissions and Their Role in Global Warming: A Review

Abstract

Livestock production contributes to anthropogenic methane emissions primarily through enteric fermentation and manure management, creating an important challenge for environmentally sustainable animal production. This review summarises the role of livestock-derived methane in global warming, with particular emphasis on the status of emissions in India and the major biological processes responsible for methane formation. Estimates based on livestock census data and IPCC-based methodology indicate that enteric fermentation represents the dominant source of livestock methane in India, while manure management makes a smaller contribution. Methane production in ruminants is closely associated with anaerobic microbial fermentation in the rumen, where hydrogen and carbon dioxide are utilised by methanogenic microorganisms. The review evaluates major mitigation approaches, including improved forage quality, tannins and saponins, probiotic supplementation, dietary lipids, methanogenesis inhibitors, nitrate supplementation, macroalgae, genetic selection, and improved manure management. These strategies differ in their mechanisms, effectiveness, and potential effects on animal nutrition and productivity. Dietary interventions may alter rumen fermentation or reduce the availability of hydrogen for methanogenesis, whereas genetic and management approaches aim to improve production efficiency and decrease emission intensity. Manure-related emissions may also be reduced through appropriate storage, treatment, composting, anaerobic digestion, and acidification. Effective methane mitigation therefore requires an integrated approach that considers emission reduction together with animal productivity, feed utilisation, and practical livestock-management conditions.