POTENTIAL OF GREENHOUSE GAS EMISSION BY FORAGE PLANTS FROM ENTERIC FERMENTATION

Abstract

Ruminants emit methane (CH4) and carbon dioxide (CO2) to the atmosphere, mainly from the fermentation of soluble and structural carbohydrates. These greenhouse gases (GHG) favor climate change and their increasingly higher concentration in the atmosphere also accelerates global warming. Therefore, various strategies have been developed to reduce their emission, such as the use of metabolic modifiers, the addition of essential oils and bioactive compounds from tropical leguminous trees, among others. However, the methodologies validated to measure GHG emission by ruminants more precisely often decrease dry matter consumption. The Intergovernmental Panel on Climate Change suggests the use of its guidelines to estimate the emission of CH4 from enteric fermentation in ruminants, and recommends generating emission factors taking into account the chemical composition of substrate and its fermentation products in order to increase precision. Anaerobic digestion and the in vitro gas production technique have been used widely to evaluate the degradation of substrates and fermentation products. Thus, these techniques may also be used to generate GHG emission factors and can be another alternative versus global warming.