Ruminal methanogenesis and mitigation strategies

摘要

Maintaining rumen fermentation depends on the removal of products generated during food degradation. Volatile Fatty Acids (VFA) are rapidly absorbed by the host animal and used as energy source, while other products such as hydrogen (H2) and carbon dioxide (CO2) are used in the rumen by Archaea microorganisms to produce methane (CH4), which is belched by the animal. Methanogenic activity generates the energy required for the survival of methanogens and maintains a low H2 pressure, creating a favorable environment for the oxidation of reduced cofactors produced during glycolysis. Despite its importance for ruminal degradation, methanogenesis represents loss of energy consumed by the ruminant and its escape to the atmosphere increases total greenhouse gas (GHG) emissions. Reducing rumen emissions of CH4 can be achieved through feeding strategies, improved animal performance, and the use of feed additives. The aim of this paper is to provide conceptual tools for understanding the origin and importance of methanogenesis in ruminal fermentation and how this process can be modulated without adversely affecting animal productivity.