The purpose of the current work was to designate effect maturity stages potential nutritive value, chemical composition, condensed tannin (CT), gas production (GP), methane production, metabolizable energy (ME), and organic matter digestibility (OMD) Rheum ribes L. Maturity significantly affected (P<0.05) CT, GP, ME OMD Dry (DM), crude ash (CA), protein (CP), ether extract (EE), neutral ...