Methane production by ruminants is a significant contributor to global warming, with agricultural emissions in the EU-15 estimated at 10.2 million tonnes per year, primarily from enteric fermentation and livestock manure. Ruminants, particularly cattle, produce methane through ruminal fermentation, where volatile fatty acids (VFAs) like acetate and butyrate promote methane production, while propionate can compete for hydrogen use. Methane emissions from ruminants are a major source of greenhouse gases, contributing to global warming. Strategies to reduce methane emissions include developing anti-methanogenic compounds, alternative electron acceptors, and reducing protozoal numbers in the rumen. Other approaches involve using ionophores, propionate enhancers, acetogens, methane oxidisers, and defaunation. Probiotics and immunisation are also being explored. Reducing feed intake or increasing animal productivity can lower methane emissions per unit of product. Diet type and forage quality significantly influence methane production, with high concentrate diets generally leading to lower methane emissions. However, increasing productivity through improved feeding practices can help balance methane production with animal output. Overall, reducing methane emissions from ruminants requires a combination of dietary, microbial, and management strategies to mitigate their environmental impact.Methane production by ruminants is a significant contributor to global warming, with agricultural emissions in the EU-15 estimated at 10.2 million tonnes per year, primarily from enteric fermentation and livestock manure. Ruminants, particularly cattle, produce methane through ruminal fermentation, where volatile fatty acids (VFAs) like acetate and butyrate promote methane production, while propionate can compete for hydrogen use. Methane emissions from ruminants are a major source of greenhouse gases, contributing to global warming. Strategies to reduce methane emissions include developing anti-methanogenic compounds, alternative electron acceptors, and reducing protozoal numbers in the rumen. Other approaches involve using ionophores, propionate enhancers, acetogens, methane oxidisers, and defaunation. Probiotics and immunisation are also being explored. Reducing feed intake or increasing animal productivity can lower methane emissions per unit of product. Diet type and forage quality significantly influence methane production, with high concentrate diets generally leading to lower methane emissions. However, increasing productivity through improved feeding practices can help balance methane production with animal output. Overall, reducing methane emissions from ruminants requires a combination of dietary, microbial, and management strategies to mitigate their environmental impact.