Detection of Taura Syndrome Virus (TSV) in Litopenaeus vannamei in the Philippines

Farming of Litopenaeus vannamei in the Philippines was seen as a measure to increase shrimp production in the country. Taura Syndrome Virus (TSV) is a viral pathogen reported to be associated with Litopenaeus vannamei and other shrimp species. TSV outbreak impedes the production of Litopenaeus vannamei population and other species susceptible to the virus. Detection of TSV in L. vannamei in the Philippines calls for proper mitigation and appropriate actions for aquaculture and environmental management towards sustainable development. This study embarked on the detection of TSV using a purposive sampling method. Samples showing morphological symptoms of TSV such as redness of the carapace and pleopods and necrotic gill tissue collected from sites in Luzon and Visayas in the Philippines were processed. Viral RNA was extracted from the gills, the central area of infiltration and replication site of the virus. Complementary DNA (cDNA) was synthesized from the RNA templates and were subjected to RT-PCR under specific conditions using TSV specific primers against a positive control. Selected sites in the Philippines were proven to be positive of infection as they showed morphological symptoms and RT-PCR result in having a band at around 200 base pairs (bp). Percentage of prevalence results were obtained: Bulacan with 5 out of 15 samples (33%), Batangas with 7 out of 15 samples (47%), Bohol with 1 out of 15 samples (7%) and Cebu with 2 out of 15 samples (13%). The Batangas samples showed the highest prevalence of 47% (7 out of 15 samples) that were positive of the infection. This study reported the presence of TSV in L. vannamei in the country using morphological and molecular techniques