Ruminant animals naturally produce methane during fermentative processes; however, this process represents a loss of dietary energy and has been scrutinized for its potential environmental impacts. Nutritional management strategies, such as the use of feed additives, have been investigated as a possible option for mitigating greenhouse gas emissions from beef cattle. Tannins are naturally occurring plant secondary compounds that have been studied as a dietary supplement for beef cattle due to their inherent ability to modulate rumen fermentation. The use of tannin extract from plants allows for supplementation at a known concentration. Condensed and hydrolyzable tannins are two primary types of tannins whose combination may yield synergistic effects when supplemented to beef cattle. Our objective was to investigate the dose–response patterns of a tannin extract containing both condensed and hydrolyzable tannins at 0.0%, 0.3%, 0.6%, and 0.9% of dry matter on methane production and diet digestibility using the in vitro gas production technique. Tannin extract inclusion below 0.3% of DM may maximize methane reduction without adversely affecting ruminal fermentation. However, further research is warranted to confirm these findings in vivo and better understand the mechanism of action of the commercial tannin extract.

Read the full article in the Journal of Animal Science.