Ovine excreta as inoculum for biogasification was used to assess in vitro and in sacco nutritive value of tropical pastures for ruminants. Pastures under study were: Paspalum notatum, Cynodon nlemfuensis, Panicum maximum, Sporobolus indicus, and Desmodium sp. Excreta were collected on grassy pastures areas. CO2 systematic injections prevented strict anaerobic microorganisms contact with oxygen. A positive and significant correlation resulted from biogasification using either ovine excreta or ovine ruminal fluid. Determinant coefficient was 0,79. Panicum maxi- mum and Cynodon nlemfuensis reached the highest nutritive value, while Sporobolus indicus showed the lowest one. Key Words: ovine excreta, digestibility, nutritive valu