In the present study, the cumulative WSSV mortalities of SPF L. vannamei were obtained from the pathogenicity outbreak of aquaculture environment.The current investigation showed that the WSSV present to infected from low level to severe level. The PCR findings revealed that the SPF Pacific white shrimp L. vannamei was presented
around five places of Tamil Nadu, the different ranges of WSSV viral infections by the 20-2 000 copies. The rests of region sample were recorded as a negative towards WSSV
436 MA Badhul Haq et al./Asian Paicfic Journal of Tropical Disease (2012)431-436
pathogen; it was shown at 848 bp as an internal control band. The viral DNA was presented the low levels (296 bp/20copies) in sample 1 and moderate level (650, 296 bp/200copies) from the sample 2 respectively. Albeit, WSSV severe level infection (910, 650, 296 bp/2000 copies) were observed from the three places of Tamil Nadu, most of WSSV infection were resulted from native shrimp P. monodon. PCR results also confirmed the above surveillance from the majority of places. Similarly, the distribution of WSSV in the distinctive place’s samples of brood stock examined; Three were apparently healthy while 7 showed gross signs of WSSV infection. The distribution of WSSV in different organs and tissues of L.vannamei was diagnosed using histopathological
tools. T he histopathological results showed different WSSV appearances in different tissue samples. The severe infected moribund shrimps strongly implied the presence
of infectious virus in all these tissues and organs of L.vannamei. The intranuclear inclusion bodies characteristic of WSSV infection in the gill lamella cells of L. vannamei showed WSSV in sample 3 and 4. Hematopoietic tissues with basophilic intranuclear inclusion bodies characteristic of WSSV in L. vannamei from sample 1 and 5. The present study showed a high frequency of WSSV by PCR in captured L. vannamei samples. WSSV prevalence was also reported to be quite high in other SPF L. vannamei animal in native species P. monodon through water contamination, collected
in nearby P. monodon shrimp farms.Conflict of interest statement