Alternative Strategies of Plant Metabolite Secondary “Tannin” for Methane Emissions Reduction on Ruminant Livestock a Reviews of the Last 5 Years Literature

An increasing global population will link the increasing livestock sector contribution to meet food security.
Recently, livestock production has encountered great challenges related to excessive methane emissions that have
a negative impact on the environment. It requires special attention to the loss of feed energy from the methane
gas formation process. Public fretfulness agreed that the gas produced by ruminants is a big factor in the effects of
global warming. Alternative the decrease in methane production from ruminants is by utilizing secondary metabolite compounds in plants. These studies are interesting to be continued and explored in an effort to reduce methane production through in vitroand in vivo, because it is proven that there are many types of biological or agro-industrial waste in the world different contents, structures and benefits. This review of the last 5 years related to the utilization of tannin active compounds showed the effect on the reduction of methane production. Condensed tannin (CT) and hydrolyzed tannin (HT) types both play an important role in reducing methane, but CT is widely studied because of its presence which is more commonly found. The concept of tannin utilization still presents its own challenges to focus on the dose of administration, the structure of the tannin itself, the substitution of other ingredients and also includes the types of animals given treatment.