Methane emission from sheep is related to concentrations of rumen volatile fatty acids

摘要

Globally, ruminants are the most important source of emission of methane (CH4). Animal-to-animal variation in CH4 emission has genetic basis (Pinares-Patino et al., 2011), hence offering a potential mitigation avenue through animal breeding. However,for this approach to progress to practical application a rapid and reliable method of ranking animals for their CH4 emissions is required. Microbial fermentation of feed in the rumen produces volatile fatty acids (VFA), hydrogen (H2), carbon dioxide (C02), ammonia and heat. A last step in the process is the reduction of C02 to CH4 by Archaea using H0 as a source of energy. Formation of both acetic and butyric acids is accompanied by the production of H2 and C02, whereas propionic production involves a net uptake of H2, hence VFA profiles may be used to predict CH4 emission rates (Benchaar et al, 2001). This controlled study conducted with sheep explored the relationship between rumen VFA and CH4 emission.