Effects of the probiotic A rthrobacter sp. CW 9 on the survival and immune status of white shrimp ( P enaeus vannamei )

The probiotic A rthrobacter sp. CW 9 isolated from guts of white shrimp ( P enaeus vannamei ) was used to improve the survival rate, growth rate and immune status of white shrimp ( P . vannamei ). A rthrobacter sp. CW 9 was added to the saline rearing water at 0, 10 5 , 10 6 and 10 7  CFU  ml −1 once every 5 days during the 24‐day breeding experiment. The probiotic group had significantly higher survival rates, mean shrimp weights, phenoloxidase activity, phagocytic activity and clearance efficiency compared with the control group ( P <  0·05). Therefore, A rthrobacter sp. CW 9 has both probiotic and immunostimulatory properties. Significance and Impact of the Study This study demonstrates that A rthrobacter sp. CW 9 has both probiotic and immunostimulatory properties. Such new strain therefore represents an alternative to the use of white shrimp ( P enaeus vannamei ) culture. New bacterial having both probiotic and immunostimulatory properties are the major novelty of this study. The results are of industrial relevance.