• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.524-525
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• 2001

White spot syndrome virus (WSSV) causes the most serious epizootic in cultured penaeid shrimp. The epizootic started in 1992, and spread through east and south east Asia and into other shrrimp growing countries of the region. In order to circumvent the epizootic, in many Asian countries, freshwater prawn, Macrobrachium rosenbergii is being widely considered as an alternative species to marine shrimp. (omitted)

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.7
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• pp.1047-1053
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• 2013

Five hundred and forty crossbred (Korean native black pig${\times}$Landrace) F2 were selected at a commercial pig farm and then divided into six different coat color groups: (A: Black, B: White, C: Red, D: White spot in black, E: Black spot in white, F: Black spot in red). Birth weight, 21st d weight, 140th d weight and carcass weight varied among the different coat color groups. D group (white spot in black coat) showed a significantly higher body weight at each weigh (birth weight, 140th d weight and carcass weight) than did the other groups, whereas the C group (red coat color) showed a significantly lower body weight at finishing stage (140th d weight and carcass weight) compared to other groups. Meat quality characteristics, shear force, cooking loss and meat color were not significantly different among the different coat color groups, whereas drip loss was significantly higher in F than in other groups. Most blood characteristics were not significantly different among the different groups, except for the red blood cells.

• Journal of fish pathology
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• v.10 no.2
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• pp.87-95
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• 1997

Baculovirus associated with white spot syndrome (WSBV) is the causative agent of a disease with high mortalities and causes severe damage to shrimp cultures. In this study, we analyzed a recombinant clone (E3) obtained from a viral genomic library to characterize the causative agent in diseased shrimp Penaeus chinensis with white spot syndrome. According to the analysis of nucleotide sequence of E3, this clone did not showed considerable sequence homology with those of other known viruses, including baculovirus Autographa californica nuclear polyhedrosis virus (AcNPV), indicating that WSBV is a novel virus causing a serious disease in P. chinensis. Based on the sequence of E3 clone, a pair of PCR primers was designed. After 30 cycles of amplification, a specific product of the expected size was detected only if the total nucleic acids extracted from the diseased shrimp was used as a template DNA, suggesting that this method can be used to diagnose the virus infection in diseased shrimp.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.511-515
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• 2007

White-spot syndrome virus (WSSV) is a devastating, infectious virus affecting shrimp. Although sensitive techniques involving PCR have been developed to assist farmers in screening shrimp (brood stock) for WSSV prior to stocking ponds, such practices have not yet been applied in Korea. Despite the rationality of implementing screening, there has been some doubt as to whether the stocking of WSSV-PCR-negative fly epidemiologically decreases white-spot disease outbreaks. Here, we report a retrospective analysis of data from shrimp farms in the western coast of Korea where WSSV-PCR-negative brood stocks were used to stock rearing ponds. A total of 366 shrimp from Heuksan Island were sampled for WSSV with PCR. Of the tested shrimp, 7.2% (28 brood stocks) were identified as WSSV positive; only WSSV-PCR-negative shrimp were used for brood stocks. Total unit production (final shrimp production/ the area of the ponds) was higher, at 1.96, in ponds where WSSV-PCR-negative shrimp were used, as compared with 1.02 in other ponds in Korea in 2004. This retrospective analysis of WSSV in Korea may be useful to the shrimp aquaculture industry, suggesting a testable hypothesis that may contribute to the eventual control of WSSV outbreaks.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.197-209
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• 1995

This paper is a third report about the new fungal diseases of economic resource plants in Korea. It contains short descriptions on symptoms, occurrence conditions, pathogen, and some phytopathological notes for each of 10 fungal plant diseases. They are angular leaf spot of Achyranthes japonica by Cercospora achyranthis causing leaf spot and defoliation in the shade of plants, leaf spot of Armoracia lapathifolia by Cercospora armoraciae causing leaf spot to blight from the rainy season to autumn, hypophyllous mold of Dioscorea tokoro by Distocercospora pachyderma causing leaf spot and yellowing, hypophyllous mold of Artemisia spp.by Mycovellosiella ferruginea causing leaf spot and yellowing, angular leaf spot of Aralia elata by Pseudocercospora araliae causing velvety leaf spot and defoliation, hypophyllous mold of Lycium chinense by Pseudocercospora chengtuensis causing velvety leaf spot and defoliation from the rainy season to autumn, angular leaf spot of Diospyros lotus by Pseudocercospora disospyri-morrisianae causing leaf spot and defoliation from summer to autumn, brown leaf spot of Impatiens textori by Pseudocercospora nojimae causing leaf spot to blight from the rainy season, leaf spot of Cephalonoplos segetum by Ramularia cirsii causing leaf spot to blight throughout the growing season, and white mold of Leonurus sibiricus by Ramularia leonuri causing leaf spot to blight mostly in autumn.

• Journal of fish pathology
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• v.27 no.1
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• pp.11-16
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• 2014

The resistance against white spot syndrome virus (WSSV) infection in wild marine crab Gaetice depressus by the immunization of a recombinant glutathione-S-transferase (GST) fused VP28 protein (GST-VP28) was evaluated. The cumulative mortalities of GST-VP28 injected groups were lower than those of the control groups at 10 days of post-challenge, and the time to death of 50% crab ($TD_{50}$) was delayed by the immunization using GST-VP28. The group boosted with GST-VP28 after 2 weeks of primary immunization clearly showed longer $TD_{50}$ than non-boosted group against challenge with WSSV. This result suggests that boosting with the antigen protein elicit stronger immune responses similar to adaptive immune responses of vertebrates. However, the short $TD_{50}$ was observed in the group challenged at 3 weeks post boosting comparing to the group challenged at 1 week post boosting. This suggests that the protective strength of immunization decreased by the time.

• Journal of fish pathology
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• v.13 no.2
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• pp.97-102
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• 2000

In order to investigate the effect of chlorine disinfectant against white spot baculovirus (WSBV), 5, 10, or 30 ppm of sodium hypochlorite (NaOCl) was treated to the WSBV-infected shrimp, Penaeus chinensis. In contrast with the non-treated control, no shrimp was dead after of sodium hypochlorite treatment. This result indicated that WSBV was inactivated by chlorine treatment. No inactivation of WSBV was observed by 10, 20, 30 ppm of povidon-iodine treatment. WSBV was also inactivated by 2, 4 hr sunlight exposure and by 1, 2, 3 hr drying. WSBV was inactivated very effectively by addition of fresh water on sea water.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.418-423
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• 2019

We report the first occurrence of Ophichthus erabo (Jordan and Snyder, 1901) collected in the waters around Jeju Island. The morphologic characteristics of this species include rich brown semicircular spots distributed on the head, the back, and the dorsal fins. Ophichthus erabo has a similar body color to Ophichthus polyophthalmus but can be clearly distinguished from the latter by the number of vertebrae (152-155 in O. erabo vs. 147-149 in O. polyophthalmus) and the existence of a white spot at the center of a semicircle (i.e., no white spot in O. erabo vs. a white spot in O. polyophthalmus). We suggest a new Korean name for O. erabo to be "Mul-bang-ul-ba-da-baem-gang-eo".

• Journal of fish pathology
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• v.33 no.2
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• pp.139-143
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• 2020

This study investigated the disinfection effect of monopersulfate (MPS) compound against white spot syndrome virus (WSSV) by bioassay using kuruma shrimp (Marsupenaeus japonicas). A WSSV stock was prepared with muscle homogenate from WSSV-infected whiteleg shrimp (Penaeus vannamei) and its lethal dose 50% endpoint (LD50) and infectious dose 50% endpoint (SID50) were respectively determined as 10-5.63 and 10-6.79 in bioassay using kuruma shrimp, followed by PCR assays. The disinfective effect of MPS compound (1.2 ppm, 2.4 ppm, 4.8 ppm) was performed by bioassay using about 10-fold higher dilution (10-4) of WSSV homogenate. The compound resulted in WSSV inactivation by a concentration-dependent manner. In addition, 4.8 ppm of MPS completely prohibited WSSV infection. To our knowledge, this study is the first report about the usefulness of MPS as a disinfectant to WSSV.

• Journal of Veterinary Science
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• v.21 no.2
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• pp.31.1-31.5
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• 2020

In this study, whiteleg shrimp (Penaeus vannamei) imported from Vietnam were collected from South Korean markets, and examined for 2 viruses: infectious hypodermal and hematopoietic necrosis virus (IHHNV, recently classified as decapod penstyldensovirus-1), and white spot syndrome virus (WSSV). Among 58 samples, we detected IHHNV in 23 samples and WSSV in 2 samples, using polymerase chain reaction and sequencing analyses. This is the first report of IHHNV and WSSV detection in imported shrimp, suggesting that greater awareness and stricter quarantine policies regarding viruses infecting shrimp imported to South Korea are required.