In vitro GAS PRODUCTION AND POST INCUBATION PARAMETERS OF FORAGE LEGUMES AS AFFECTED BY PROCESSING METHODS

Abstract

ABSTRACT The study investigated the effects of different processing methods (fresh, wilted, and sun-dried) on the proximate composition, in vitro gas production and post-incubation parameters of two legume species pigeon pea (Cajanuscajan) and Bambara Groundnut (Vigna subterranean). Sun-drying enhanced (DM) and (CP) content, with pigeon pea reaching the highest CP (22.30%) across all methods. pigeon pea consistently showed higher fat content (EE), 12.87% when sun-dried. B. Groundnut exhibited lower fat levels, with fresh samples containing the least (0.97%). Ash content was highest in sun-dried B. Groundnut (20.87%), while P. Pea generally had lower ash, especially in fresh and sun-dried forms. Neutral detergent fiber (NDF) was more prevalent in P. Pea, particularly in fresh and sun-dried samples, indicating higher fiber content compared to B. Groundnut. B. Groundnut generated significantly more gas at both 12 hours (9.83 mL/200mg DM) and 24 hours (18.17 mL/200mg DM) than P. Pea. Wilted samples of both legumes produced the most gas overall. Sun-dried samples yielded the highest methane (6.83 mL/200mg DM), while B. Groundnut produced more carbon dioxide (CO₂) than P. Pea. Wilted samples showed the highest in vitro dry matter digestibility (IVDMD) at 69.25%, while sun-dried samples maximized organic matter digestibility (OMD). Sun-dried samples also exhibited the highest metabolizable energy (ME) at 15.94 MJ/kg. Short-chain fatty acids (SCFA) were most abundant in wilted and sun-dried samples. in conclusion, Sun drying increases the concentration of most nutrients, though it also elevates ash content, particularly in B. Groundnut. Wilting is effective in reducing NDF content, potentially improving digestibility. Sun drying is recommended when the goal is to maximize DM, CP, and EE content in forage legumes. Care should be taken due to the associated increase in ash content Sun drying is recommended when the goal is to maximize DM, CP, and EE content in forage legumes.