Effects of long-term supplementation of Caesalpinia coriaria fruit extract on ruminal methane, carbon monoxide, and hydrogen sulfide production in sheep

This study aimed to evaluate the long-term effect of oral administration of Caesalpinia coriaria Jacq (Cascalote) wild fruit extract to lambs on ruminal methane, carbon monoxide, and hydrogen sulfide production and in vitro fermentation profile. Rumen liquor (RL) was collected from lambs administered with 0- (RL0), 30- (RL30), and 60- (RL60) mL of aqueous extract of the C. coriaria fruit for 60 days per lamb, as well as during incubation, 0-, 0.6-, 1.2-, and 1.8- mL of C. coriaria fruit extract was added to each RL type. There was a dose-dependent increase in gas production with increasing levels of C. coriaria extract. The RL30 lambs had the lowest ( P = 0.013) methane output (g CH 4 /kg DM) at 24 h, and RL30 with 1.8 mL/g DM had the lowest ( P = 0.031) CH 4 (g CH 4 /kg DM) at 48 h. Furthermore, diets fermented with RL0 produced the highest ( P = 0.001) short-chain fatty acid (SCFA, mmol/g DM) and metabolizable energy (ME, MJ/kg DM 24 h), while diets incubated with RL30 produced the lowest. Without plant extract addition, 30 mL oral supplementation of C. coriaria fruit extract/day/lamb was optimal for digestion, ME, and SCFA. Therefore, 60 mL/d/lamb containing 1.2–1.8 mL fruit extract/g DM seemed to be a feasible means of decreasing emissions of gas production, ME, SCFA, CO, H 2 S, and CH 4 . Graphical abstract