After 8 weeks of the feeding period, shrimp fed BM8 and BM5 diets and the control were infected with V. harveyi. Cumulative mortality of shrimp after being injected with a high dose (106 CFU shrimp1) of V. harveyi showed significant differences (P < 0.05) between BM8 (20 10%) and BM5 (33.3 5.7%) compared to the control group (63.3 15.3%) (Fig. 2). No mortality was observed in shrimp from the positive control which had been injected with NSS.