Screening the organs for early detection of white spot syndrome virus in Penaeus indicus by histopathology and PCR techniques

PCR and histopathological observations were carried out at different time intervals to detect white spot syndrome virus (WSSV) in shrimp samples obtained from time-course experiments. Histopathological observations revealed the presence of intranuclear inclusion bodies in gill tissue, eyestalk, appendages and connective tissue at 36 h post-infection (p.i.) and in heart and stomach at 48 h p.i. The PCR analysis showed that hemolymph was positive for WSSV at 6 h p.i. and all other organs at 12 h p.i. For both techniques, the use of eyestalk as material for WSSV detection was suitable and allows for sample collection without sacrificing the shrimp. Eyestalk samples can be used for nonlethal screening of Penaeus indicus to detect WSSV in positive samples as early as 12 h p.i. by PCR, or 36 h p.i. by histology.