Specific activity of amylase in hepatopancreas was 57.6% significantly higher (p < 0.01) in B4 compared with control (Fig. 1)while no significant difference was noticed among B8, B12 and control, B0. However, gut amylase activity did not differ significantly (p > 0.05) among the treatments. Cellulase activity in hepatopancreas differed significantly (p < 0.01) with the highest specific activity in B4 which was 45.5 and 112.5% significantly higher compared to B0 and B12 respectively (Fig. 2). As for gut, the highest cellulase (p < 0.05) activity recorded in B8 (0.05± 0.01 U mg−1 protein) and the lowest activity in control (0.02 ± 0.001 U mg−1 protein).