Songklanakarin Journal of Science and Technology (SJST) (Sep 2007)
Epizootic and pathogenesis of Taura syndrome virus (TSV) in black tiger shrimp (Penaeus monodon) cultured in southern Thailand
Abstract
A research study was carried out on Taura syndrome virus (TSV) in P. monodon and P. vannamei cultured in earthen ponds of Songkhla, Satun and Pattani provinces. Infection rates of 38.33 and 34.21% were detected in P. monodon and P. vannamei, respectively. The injection of Taura virus isolated from the infected specimens of both species in 3-5 g P. monodon juveniles then reared in seawater with 3.25 and 5.74 mg DO for a 15-d period. The mortality rates of 16.67 and 30% were recorded in shrimps injection with TSV solution and reared in 5.74 mg DO seawater, while mortality increased to 50-70% when reared in 3.25 mg DO seawater. TSV infected P. monodon showed aggregated multifocal necrotic foci in epithelial tissues of subcuticle, stomach, haemopoietic tissue and to lesser extent in gill, tegmental and antennal glands. Application of in situ hybridization technique with DNA probes to examine the target organ of TSV showed specificity of infection for subcuticle, epithelial tissues of stomach, intestine and haematopoietic tissue is major target organ of infection, with densely dispersed inclusion bodies and multifocal necrotic foci. Penetration of TSV into the cells can cause damage to tissue of antennal gland, gill, lymphoid organ, subcuticle and connective tissue, remarkably noted of no infection in hepatopancreas, nervous tissue, anterior midgut cecum and epicardium tissue.
