Strategies to Reduce Methane Production in Ruminants

Ruminant animals play an important role in the food chain for evaluate cellulose and non-protein nitrogenous (NPN) compounds absorbed partially or not by other farm animals and humans. However, ruminant animals also bring some disadvantages. Methane, produced as a natural consequence of the ruminal digestion and it is a potential green house gas, is a problem, both ecologically and economically. Methane emissions from ruminant livestock are a contributor to total global anthropogenic emissions of greenhouse gases which have a global warming potential. Also methane produced by ruminants represents a loss of energy for ruminants. Methane is formed in the fore-stomach (reticulorumen, more commonly known as the rumen) of ruminants by a group of microbes called methanogens, which form a subgroup of the domain Archaea. Their effect on producing methane is mentioned. In this review, current approaches towards mitigation of methane in pastoral farming are summarised. The strategies to diminish methane output from livestock are required for ecological and economical dairy production. Research strategies based on vaccination, enzyme inhibitors, phage, homoacetogens, feed supplements, and animal selection are reviewed. Numerous studies have been completed on use of plant secondary metabolites (PSM) in substitute for chemical feed additives because some of them modify rumen fermentation and reduce CH4 production. Also this review describes the basic conceptual aspects of ruminal methanogenesis, which is a way of keeping a low H2 pressure in the rumen by reducing CO2, and steps where it may be possible to intervene to reduce CH4 production