EARLY MORTALITY SYNDROME, NO MORE: PROBIOTIC FROM TILAPIA GREEN WATER Psuedomonas luteola INHIBITS GUT COLONIZATION, PREVENTS Vibrio parahaemolyticus INFECTION AND ENHANCED GROWTH PERFORMANCE OF Penaeus monodon

The significant decline in global shrimp production due to Early Mortality Syndrome disease outbreak has caused panic among shrimp growers and becomes a pressing concern requiring a rapid, practical and applicable solution. In an attempt to elucidate the Vibrio inhibitory activity of Tilapia green water, we have isolated Pseudomonas luteola, exhibiting potent secreted antibiotic effects against Vibrio parahaemolyticus. In this report, we tested P. luteola pathogenicity against P. monodon and its efficacy to protect the shrimp against Vibrio parahaemolyticus infection. To test for pathogenicity, shrimp were exposed to increasing levels of P. luteola and mortality recorded daily for two weeks. To test the efficacy of this probiotic against V. parahaemolyticus infection. Two groups of post larvae were tested with one group received diets supplemented with P. luteola at 10⁹ cfu/g and the other group received no probiotic. Following a month of feeding, the shrimp were subjected to V. parahaemolyticus infection challenge test. Our results indicate that P. luteola is not pathogenic to shrimp, no mortalities were observed in all treatment groups. The feeding trial indicates that shrimp in the treated group exhibited higher survival and improved growth performance than the control group. The improved growth in the treated group is associated with a low gut content of V. parahaemolyticus indicating the active exclusion of this pathogen in the gut. The infection challenge test with pathogenic V. parahaemolyticus administered via oral route indicates that the group receiving the probiotic has significantly higher survival than the control group. Lower counts of V. parahaemolyticus in the gut of the probiotic treated group were also recorded.  Collectively our results indicate that application of probiotic P. luteola is an effective, practical and applicable means to prevent V. parahaemolyticus infection in P. monodon culture.