Effect of probiotics on white shrimp (Penaeus vannamei) growth performance and immune response

The present research evaluated the effects of probiotics, Lactobacillus acidophilus RS058, Rhodopseudomonas palustris GH642 and Bacillus coagulans NJ105, as water additives on growth performance and immune response of the white shrimp, Penaeus vannamei. The shrimp, with average weight of 3.38 +/- 0.13 g, were stocked in each of the 12 500-litre polypropylene tanks, with three tanks treated with L. acidophilus RS058 (T-1), R. palustris GH642 (T-2) and B. coagulans NJ105 (T-3), respectively, at a final concentration of 1 x 10(7) cfu ml(-1) every day, and the remaining three tanks were without any probiotic and served as the control. The trial was carried out for 35 days and the results indicated that probiotic treatments significantly improved the final weight, daily weight gain (DWG) and relative weight gain (RWG) of the shrimp (P<0.05) as compared with those of the control. There were no significant differences (P>0.05) in final weight and RWG among the treatments. As for T-1, no significant differences were observed in DWG and SOD activity compared with T-2 and T-3. However, higher DWG (P<0.05) was observed in T-3 compared with T-2. A substantial and significant increase (P<0.05) in phenoloxidase (PO) activity was found in T-3 compared with those of the other two probiotic treatments. The activity of superoxide dismutase (SOD) was significantly higher for the shrimp in T-3 than that in T-2. There were no significant differences (P<0.05) in the peroxidase (SOD) activity and antibacterial activity among the shrimp treated with different probiotics.