Abstract
Livestock production accounted for a significant share of global greenhouse gas (GHG) emissions, particularly methane (CH₄) and nitrous oxide (N₂O), posing critical challenges in the context of climate change. Several mitigation strategies were proposed, showing variable effectiveness depending on the approach and production system. Objective: To systematically review scientific evidence published between 2016 and 2024 regarding GHG mitigation strategies in livestock systems, with emphasis on nutritional supplementation, manure management, and genetic improvement. Methods: A systematic review was conducted following the PRISMA 2020 guidelines. Scientific literature was retrieved from Scopus, Web of Science, PubMed, Scielo, and Google Scholar. Eligible studies included experimental trials, reviews, and meta-analyses reporting quantifiable reductions of CH₄ or N₂O in ruminants. Results: Supplementation with nitrates and red seaweed (Asparagopsis spp.) showed CH₄ reductions ranging from 20% to 50%, depending on diet composition and rumen adaptation. Technologies such as anaerobic biodigesters and controlled aerobic composting achieved up to 60% reduction in manure-related emissions. Genetic selection based on residual feed intake (RFI) and rumen microbial profiles was identified as a cumulative mitigation pathway, though still underused in Latin America. Conclusions: The reviewed strategies demonstrated strong mitigation potential, particularly when integrated synergistically. Effective adoption required public policies promoting innovation, access to technology, and technical capacity building in livestock systems.