Genetic aspects of enteric methane emission in livestock ruminants

This review summarizes the importance of enteric methane (CH4) emission in ruminants and summarizes the current state of knowledge relevant to genetic aspects on enteric methane production, highlighting future research needs and directions. Global average temperature has increased by about 0.7 degrees C in the last century. The Intergovernmental Panel on Climate Change (IPCC) reported that anthropogenic greenhouse gases (GHG), including carbon dioxide (CO2), CH4, nitrous oxide (N2O) and halocarbons, have been responsible for most of the observed temperature increase since the middle of the twentieth century. Agriculture, particularly livestock, is increasingly being recognized as both a contributor to the process and a potential victim of it. Policy interventions and technical solutions are required to address both the impact of livestock production on climate change and the effects of climate change on livestock production. Food and Agriculture Organization (FAO), declared that in the next 50 years, the world's farmers will be called upon to produce more food than has been produced in the past 10,000 years, and to do so in environmentally sustainable ways. Therefore, the GHG reduction should be treated as a public good. The United States congress is prospecting to define a price on GHG emissions. Limiting the concentration of CO2 and other GHG in Earth's atmosphere requires a technological and economic revolution. A cost-effective way could be the genetic improvement of livestock, which produces permanent and cumulative changes in performance. Animal variation in enteric CH4 emission has been reported in the literature, providing potential for improvement through genetic selection.