Methane （CH₄） is recognized as the second-largest contributor to greenhouse gas emissions. The enteric fermentation from ruminant livestock accounts for approximately 40% of the total anthropogenic CH₄ emissions. This poses a major obstacle to national efforts in combating global warming and achieving the “dual carbon goals”. In this study， we systematically synthesized the existing knowledge on enteric methane emissions from ruminant livestock and their measurement methods. The results indicated that there were significant variations in CH₄ emission factors across regions， livestock species and feeding stages. There was a larger span of emissions in warmer and humid regions than in colder and drier regions. Larger-bodied animals generally produced higher emissions. For example， female breeding buffaloes emited up to 110.6 kg·head^-1·a^-1， whereas emissions from sheep and goats were considerably lower （approximately 12~13 kg·head^-1·a^-1）. Overall， the emission factors ranged widely from 6.5 to 110.6 kg·head^-1·a^-1 depending on production stages and feeding systems. Key measurement techniques for enteric methane included the sulfur hexafluoride （SF₆） tracer technique， respiration chamber/headbox systems， the GreenFeed system， in vitro fermentation， laser-based methods， and predictive modeling. Promising mitigation strategies encompassed dietary composition adjustments， feed additives， rumen microbiota manipulation， vaccine-based methods， genetic improvement， and optimized management practices， as well as emerging approaches such as targeted inhibition of key methanogenic enzymes， modulation of hydrogen metabolic shunting， and remodeling the rumen microbiome through gene editing. Future studies should prioritize establishing accurate methodologies for accounting enteric CH₄ emissions throughout the entire production cycle. In addition， more studies are needed to refine region-specific emission factors. For greenhouse gas mitigation， efforts should focus on improving dietary formulations， integrating farm management， and implementing genetic selection programs to promote the sustainable development of ruminant livestock production.

Rumen  /  Livestock  /  Ruminants  /  Greenhouse gases  /  Intestinal methane