Methane mitigation in ruminants for sustainable livestock production in tropical climates

Livestock production plays a vital role in food security and rural livelihoods, particularly in tropical regions, where methane emissions from ruminant animals contribute significantly to global greenhouse gas outputs. In addition to its environmental impact, enteric methane produced during rumen fermentation represents an energy loss that reduces feed efficiency. Consequently, mitigating methane emissions is essential for improving both the sustainability and productivity of livestock systems. Methanogenesis can be reduced and rumen fermentation modified through nutritional strategies, including lipid supplementation, phytogenic compounds, and feed additives such as tannins, saponins, and essential oils. Methane mitigation strategies encompass a broad range of approaches, including nutritional interventions, microbial and genetic manipulation, and improved livestock management practices. Among these, nutritional strategies such as feed additives, dietary manipulation, and the use of improved forages remain the most practical and immediately applicable options, particularly in tropical livestock systems where low-quality feed resources are a major driver of methane production. In addition, microbial approaches aimed at modifying rumen fermentation, together with genetic selection for more feed-efficient and low-emitting animals, provide promising pathways for long-term emission reduction. Emerging technologies, including rumen microbiome engineering, artificial intelligence-based monitoring systems, and precision livestock farming, further offer innovative opportunities to enhance methane mitigation efficiency while simultaneously improving animal productivity and environmental sustainability. In tropical regions, implementation is further constrained by seasonal feed scarcity, dependence on low-quality forages, financial constraints, limited infrastructure, and the predominance of smallholder extensive production systems. Widespread adoption will require supportive policies, farmer awareness, and effective extension services. This review highlights the need for integrated, region-specific strategies that combine nutritional, genetic, microbial, and management interventions. The adoption of climate-smart livestock practices offers significant potential to reduce methane emissions while maintaining productivity and environmental sustainability in tropical livestock systems.