Research Progress on Methane Emission Reduction Strategies for Dairy Cows

Methane (CH4) is the second largest greenhouse gas (GHG) after carbon dioxide (CO2), and ruminant production is an important source of CH4 emissions. Among the six types of livestock animal species that produce GHGs, cattle (including beef cattle and dairy cows) are responsible for 62% of livestock-produced GHGs. Compared to beef cattle, continuous lactation in dairy cows requires sustained energy intake to drive rumen fermentation and CH4 production, making it a key mitigation target for balancing dairy production and environmental sustainability. Determining how to safely and efficiently reduce CH4 emissions from dairy cows is essential to promote the sustainable development of animal husbandry and environmental friendliness and plays an important role in improving feed conversion, reducing environmental pollution, and improving the performance of dairy cows. Combined with the factors influencing CH4 emissions from dairy cows and previous research reports, this paper reviews the research progress on reducing the enteric CH4 emissions (EMEs) of dairy cows from the perspectives of the CH4 generation mechanism and emission reduction strategies, and it summarizes various measures for CH4 emission reduction in dairy cows, mainly including accelerating genetic breeding, improving diet composition, optimizing feeding management, and improving fecal treatment. Future research should focus on optimizing the combination of strategies, explore more innovative methods, reduce EME without affecting the growth performance of dairy cows and milk safety, and scientifically and effectively promote the sustainable development of animal husbandry.