• Journal of fish pathology
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• v.22 no.1
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• pp.15-21
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• 2009

White spot syndrome virus (WSSV) is a strong causative agent for high mortality in cultured and wild shrimps. From this study, the WSSV prevalence in marine organisms around shrimp farm as well as live feed-mediated transmission of WSSV to farmed shrimps were investigated. Based on nested-PCR method, WSSV was detected in wide array of marine organisms including Perinereis aibuhitensis (81.3% of prevalence rate, 13/16), Enedrias fangi (100%, 16/16), Ruditapes philippinarum (20%, 2/10), crab larvae (100%, 10/10), copepoda (30%, 3/10), Periophthalmus modestus (50%, 5/10), Pachygrapsus crassipes (10%, 1/10), Helice tridens (20%, 2/10) and Neomysis sp. (70%, 7/10). On the other hand, WSSV was not detected in Bullacta exarata, Uca arcuata, and Reishia clavigera. The percent prevalence of WSSV in wild shrimps, Fenneropenaeus chinensis was only 6%, but markedly increased up to 56% after a feeding trial using polychaete worms for one month, indicating that the live feed is one of significant carriers of WSSV to shrimps under practical farming conditions.

• Journal of Life Science
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• v.20 no.9
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• pp.1294-1298
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• 2010

White spot syndrome virus (WSSV) is one of the most virulent viral agents threatening the penaeid shrimp culture industry. This study was carried out to evaluate the susceptibility of the sand shrimp, Crangon affinis, to WSSV as an alternative experimental model. WSSV caused 100% mortality in C. affinis within 7 days after experimental infection by immersion. Based on challenge studies, it was confirmed that C. affinis could be a potential host in WSSV transmission. Also, the neutralization of WSSV was carried out using an antiserum raised against recombinant envelop protein rVP466 to evaluate the WSSV infection mechanism. A constant amount of WSSV (at $1{\times}10^4$ diluted stocks) was incubated with various amounts of antiserum and then mixed to 20 l reservoir for the immersion challenge of C. affinis for neutralization. At 5 days post challenge, the shrimp in the positive control immersed in the immersion reservoir containing WSSV stock showed 100% mortality. The shrimps challenged with the 3 different mixtures of WSSV and rVP466 antiserum (1:0.1, 1:0.5 and 1:1) showed 100%, 68.8% and 68.8% mortality at 14 days post challenge, respectively. These results indicated that the antiserum raised against rVP466 could block WSSV infection in C. affinis. Therefore, this study confirmed that C. affinis can be naturally infected by WSSV as another potential host and that C. affinis can be used as an alternative experimental animal instead of penaeid shrimps.

• Journal of fish pathology
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• v.34 no.2
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• pp.141-147
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• 2021

In this study, of the imported shrimps between 2017 and 2020, we investigated white spot syndrome virus (WSSV), covert mortality nodavirus (CMNV) and decapod iridescent virus 1 (DIV-1). Of the imported shrimps (a total of 29 groups), WSSV was detected as 31% (9/29) by nested PCR assay. And CMNV and DIV-1 were not identified in this study. To investigate the genetic relatedness of WSSV identified from imported shrimp, VR 14/15 region showed WSSV genomic variable loci was compared with reference isolates. Among the nine WSSV-positive samples, VR 14/15 region was amplified in only a sample (20-CH-1 isolate, imported from China in 2020). And the 20-CH-1 isolate showed 99.8% identity with WSSV-IN-05-01 which was reported in India in 2005, suggesting that those of WSSV have been spread from India to China. Furthermore, although the pathogenicity of WSSV identified from frozen shrimp was not evaluated, the international trade of diseased frozen shrimps could be led to the potential risk of virus transmission.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.133-139
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• 2023

The advantage of biofloc technology (BFT) in aquaculture is in the prevention of pathogenic transmission. In this study, we performed an investigation on viral, bacterial, and microsporidian parasite infections targeting a total of 194 whiteleg shrimp Litopenaeus vannamei reared in seven BFT-farms on the west coast of Korea in 2021. Hepatopancreatic and cuticular epithelium and pereiopods tissues of shrimp were tested for the four pathogens, Enterocytozoon hepatopenaei (EHP), Vibrio parahaemolyticus causing Acute Hepatopancreatic necrosis disease (VP_AHPND), white spot syndrome virus (WSSV), and hepatopancreatic parvovirus (HPV). The microsporidian parasite EHP was detected in the hepatopancreatic tissue of BFT whiteleg shrimp in the Ganghwa region, whereas no other pathogenic bacteria or virus was detected on the shrimp in the seven BFT-farms. As a result of bacterial flora in the rearing water of BFT whiteleg shrimp using DNA microbiome technology, V. chemaguriensis and V. alfacsensis were contained at 0.05% and 0.01%, respectively, but no VP_AHPND was detected. These findings will serve as a basis for supporting safe BFT-aquaculture of whiteleg shrimp.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.474-482
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• 2019

Disease monitoring in wild aquatic animals is necessary to obtain information about disease occurrence, disease agents, and the transmission of diseases between wild and cultured species. In this study, we monitored viral diseases in wild marine fish and crustacea caught by trawl in Korea in April and October 2018. We monitored the viral diseases in 977 fish from 39 different species and 287 crustacea from 14 different species. In fish, we collected kidney and spleen to detect viral hemorrhagic septicemia virus (VHSV), red sea bream iridovirus (RSIV), marine birnavirus (MABV), hirame rhabdovirus (HRV), and lymphocystis disease virus (LCDV). In crustacea, we monitored white spot syndrome virus (WSSV), infectious hypodermal and hematopoietic necrosis virus (IHHNV), taura syndrome virus (TSV), infectious myonecrosis virus (IMNV), yellowhead disease virus (YHDV), and white tail disease virus (WTDV) using pleopods, pereiopods, gills, muscle, and hepatopancreases. Although none of the viral diseases tested in this study were detected in the samples, these results will help disease control between aquaculture species and wild aquatic animals.