Piyalai Hemtanon, Sathaporn Direkbusarakom, and Witsanu Bunyaviwat

pp. 253 - 263

Abstract

In this study, the extract of Spirulina platensis were examined in vitro to inhibit white spot syndrome
virus (WSSV) and application of dry S. platensis in diet for prevention of white spot syndrome (WSS) in post
larvae and juvenile black tiger shrimp (Penaeus monodon). The results showed that the lowest concentration
of the extract for inhibiting WSSV was 0.01 mg/ml, while the optimum concentration was found to be 0.1 mg/
ml in which the mortality rate of the shrimp was 4 percents and infection was not detected from survival
shrimp by the immunohistochemistry method.
Furthermore, The results showed that the survival rate of the post larvae fed on steamed egg containing dry S. platensis 5 g/kg of diet was higher than that of the control (p<0.05) when challenged with WSSV and
no WSSV infected shrimp examine by polymerase chain reaction (PCR) assay. In the case of juvenile shrimp,
the survival rate of shrimp fed pellets containing dry S. platensis 10 g/kg of diet was higher than that of the
control group (p<0.05) after challenging with WSSV. Moreover percent of WSSV infection in the survival
shrimp using the immunohistochemistry method was lower than that of the control group.