The ongoing global demand to discover alternative strategies to mitigate methane emissions from farm animal production continues to rise. No studies have investigated the potential effects of breaking down the cell walls of methane-producing archaeal species that are responsible for ruminal methanogenesis using endo-1,3-β-D-glucanase. In the current study, increasing endo-1,3-β-D-glucanase (0, 5, 10, 25, 50, and 100 units/100 mL) was evaluated with high-forage, high-concentrate, and mixed forage:concentrate diets using an in vitro rumen fermentation model. In vitro methane production was not influenced by the endo-1,3-β-D-glucanase. Endo-1,3-β-D-glucanase altered the short-chain fatty acid (SCFA) profile by decreasing 2-carbon acetate proportion and increasing 3-, 4-, and 5-carbon SCFA proportions (propionate, butyrate, valerate). These data may suggest an increase in ruminal carbon and hydrogen retention as SCFAs. Factors contributing to the lack of response in methane production can include the source of endo-1,3-β-D-glucanase, suboptimal pH and/or temperature for enzymatic action, or additional enzymes required for archaeal cell wall hydrolysis. Endo-1,3-β-D-glucanase effects were similar among diets varying in forage:concentrate. Decreasing forage:concentrate affected gas and methane production, digestibility, and SCFA profiles. More research is needed to better understand how endo-1,3-β-D-glucanase can be incorporated into beef cattle diets to modulate ruminal fermentation for improved efficiency of end-products produced.

Read the full article in the Journal of Animal Science.