Measurement of methane emissions in cattle with infrared gas analyzer and gas chromatography

Abstract

Global ly, the livestock sector represents 14.5% of greenhouse gas (GHG) emissions from cattle production (4.6 Gt CO2-eq), mainly through enteric fermentation (2.1 Gt CO2-eq), which corresponds to the largest source (IPCC, 2007; Gerber et al. 2013). Enteric methane (CH4) emissions are highly variable, depending on the quality of feed, but also on climate conditions, dry matter intake and energy use. In order to contribute to the mitigation of climate change there is the current need to standardize accurate, affordable, and logistically simple methods to determine in vivo emissions of enteric CH4 accurately and at the more specifi c scales as possible. However, for the cattle sector, most of the default values given by the intergovernmental panel on climate change (IPCC) (Tier 1 emission factors) (Gavrilova et al. 2019) use to estimate emissions were developed in laboratories with mostly breeds and feeds in non-Tropical countries, which lead to uncertainties in estimations when used in the tropics. Therefore, it remains unclear whether IPCC emission factors are reflective of CH4 emissions from cattle in tropical locations.