Minimizing direct greenhouse gas emissions in livestock production: The need for a metabolic theory

摘要: Abstract Livestock production is one of the main contributors to global greenhouse gas (GHG) emissions. The tools provided by Intergovernmental Panel on Climate Change estimate GHG emissions (Tier 1 and Tier 2) cannot be used as a tool for advising farmers or national policy how minimize because these estimates are not explicitly related any metabolic properties. For that, we need model that obeys mass energy balances models trade-offs between different allocations in organism, throughout life-cycle, function environmental variables such temperature amount type food. Dynamic Energy Budget (DEB) Theory ensures conservation transformations state variable product formation, allowing explicit estimates. Therefore, this theory build four bovine breeds – Alentejana, Angus, Charolais Limousin. goodness-of-fit DEB data good all breeds. Differences breed specific parameters, maximum reserve density assimilation rate, explain differences emissions, ultimate lengths weights von Bertalanffy growth rates. Accumulated methane nitrogen ranges 0.2 2, 0.1 0.7 kg per kg body weight, respectively. In terms accumulated direct there strong dependence age.