The aim of the present study was conducted to survey effect of adding different levels (0 and 0.15 ml/30 ml buffered rumen fluid) of zataria multiflora water extract (ZMWE) on soybean meal (SBM) degradability were studied by in vitro gas producing techniques. Gas production test with mixtures of filtered rumen liquid of three Taleshi native male cattle rumen in times of 2, 4, 6, 8, 12, 24, 48, 72 and 96 hours were performed. The results showed that gas volume at 24 h incubation (for 200 mg dry samples), were 56.38 and 56.21 ml/200 mg DM for soybean meal, and zataria multiflora water extract (0.15ml/30ml buffered rumen fluid) respectively. Gas volume at 48 h incubation (for 200 mg dry samples), were 62.43 and 62.12 ml/200 mg DM for soybean meal, and zataria multiflora water extract (0.15 ml/30 ml buffered rumen fluid) respectively.
