One strategy that can reduce CH4 emissions is the addition of fat to the diet of ruminants
Another effective strategy for reducing enteric CH4 emissions from ruminants involves including condensed tannins (CT) in their diet
Grape marc is the skins, seeds, and stems that remain after grapes (Vitis vinifera) have been pressed to make wine. Grape marc contains high concentrations of both fat and tannin
In one experiment, when cows were fed 20% of their dietary DMI as ensiled grape marc (EGM), no negative effects were observed on their DMI, milk yields or milk composition
In vitro studies have shown that tannin extracted from grape seed can reduce CH4 production but little information
is available concerning the nutritional value of grape marc as a ruminant feed and its potential to reduce CH4 emissions from ruminants. Theoretically, the fats and tannins in grape marc may inhibit CH4 emissions if fed to ruminants. However, how the fats and tannins in grape marc interact with the ruminal microbiota is not known
Methane (CH4) is a potent greenhouse gas Enteric CH4 emissions from ruminants amount to approximately 80 million tonnes annually and account for approximately 28% of global anthropomorphic CH4 emissions
Interest is growing in developing practical nutritional strategies for ruminants that will reduce these emissions.