The impacts of leucaena (Leucaena leucocephala) feeding systems on cattle production, environmental services and animal welfare in Mexico are discussed. A total of about 12,000 ha of leucaena have been established in the tropical regions of México, where most of the information for the current review was obtained. Incorporating leucaena in a grass pasture increases dry matter intake of grazing cattle and reduces the level of methane produced. This results in improved liveweight gains and milk yields as well as a reduction in the level of greenhouse gas released. Additional benefits are increases in soil carbon and nitrogen levels and less stress on animals as the leucaena plants provide shade and reduce environmental temperatures. While these benefits are substantial, the area developed to leucaena represents less than 0.1% of the area which could potentially be developed. Strategies to increase adoption of these grass-legume systems by farmers need to be developed to make effective use of the systems for increasing beef and milk production while reducing the undesirable environmental outcomes normally associated with ruminant production.
