• Bacillus P11;
  • Bacillus S11;
  • Bacillus subtilis;
  • Litopenaeus vannamei;
  • Pacific white shrimp;
  • probiotic bacterium


The effect of Bacillus S11 (BS11)- and/or Bacillus P11 (BP11)-supplemented feeds on the growth performance, survival, immunoenhancement and disease resistance of cultured Pacific white shrimp, Litopenaeus vannamei, was evaluated. Four feeding treatments of (i) regular feed (control), (ii) BS11-supplemented feed, (iii) BP11-supplemented feed and (iv) BS11-and BP11-supplemented feed were prepared and used for shrimp cultivation in closed recirculating cement tanks (~400 L) in two trials, one for juvenile and PL-30 shrimp at 60 and 90 days, respectively. The results showed that BS11 gave a higher probiotic potential than BP11 for both age groups of L. vannamei in cultivation, because the average weight and survival of shrimp fed BS11-supplemented feed were significantly higher (P < 0.05) than those of the control and the other two groups. The survival of shrimp fed either BS11-or both BS11-and BP11-supplemented feed was significantly higher (P < 0.05) than that of the control group. In addition, the highest total haemocyte and granular haemocyte counts and phenoloxidase activity were found in shrimp fed with the BS11-supplemented feed. After challenge with Vibrio harveyi 639 (~107 CFU mL−1) by immersion, the lowest cumulative death (%) and disease resistance were clearly found in shrimp fed with the BS11-supplemented feed.