White spot syndrome virus (WSSV) and prevalence of disease resistance in a commercially cultured population of Penaeus monodon Fabricius, 1798 (Decapoda, Dendrobranchiata)

Abstract

White spot disease (WSD) caused by the white spot syndrome virus (WSSV) is the leading cause for huge economic destruction in the shrimp aquaculture industry. The present study investigates the prevalence of WSSV and disease-resistant shrimps among a commercially cultured population of Penaeus monodon Fabricius, 1798. Results suggest that WSSV prevalence among 32 culture ponds affected by various diseases was 58.2% cumulatively in 2009 and 2010. Real-time PCR yielded 1.46 × 108, 1.94 × 106 and 3.6 × 104 copies of WSSV per μg of genomic DNA of shrimp in severe, moderate and low infected shrimps, successively. Among the shrimps collected, the prevalence of disease resistance was 31.4% and 37.1% consecutively in 2009 and 2010. It was found that 34% of the shrimps were disease resistant while considering both years. This study shows the importance of using disease-resistant seeds for better shrimp health management.