Effect of dry leaves of Senna gardneri on in vitro dry digestibity and methane emission in cattle

Methane emissions from ruminants, especially cattle, constitute a significant source of anthropogenic greenhouse gases creating considerable obstacles for achieving sustainable livestock farming. This investigation aims to assess the effectiveness of Senna gardneri, a tannin-containing plant, in reducing in vitro methane emissions and dry matter digestibility (DMD) in cattle. Dry Senna gardneri leaves were incorporated into total mixed rations (TMR) in varying concentrations from 0% to 8%, with a corresponding decrease in wheat straw content. Rumen fluid was collected from experimental cattle, processed and analyzed for methane production and DMD using gas chromatography. The results showed no significant variation in in vitro dry matter digestibility (IVDMD) compared to the control TMR. Methane emissions were notably reduced with Senna gardneri supplementation, with mean observed values of total gas production, CH4 (ml/100 mg of DM) and CH4 (ml/100 mg of DDM) recorded at 9.00, 1.17 and 2.39, respectively for 2% supplementation. These findings indicate that Senna gardneri shows promise as a promising anti-methanogenic feed additive to curb methane emissions without negatively impacting feed digestibility, thereby supporting more sustainable ruminant livestock production practices.