• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.566-571
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• 2020

To classify a presumed hybrid of imported grouper species acquired from the National Fishery Products Quality Management Service, maternal and paternal lines were identified based on partial sequencing of mitochondrial cytochrome c oxidase 1 (co1) and nuclear recombination activation gene 1 (rag1) genes. The matrilineal species was identified as Epinephleus moara by a partial (760 bp) co1 sequence. Ambiguous sequences with base pairs belonging to E. moara or E. lanceolatus were found in a total of 15 different base pairs in the partial 1,159 bp of the rag1 gene, and the patrilineal species was found to be E. lanceolatus. Therefore, all of the groupers examined in the study were identified to be hybrids of E. moara and E. lanceolatus. In addition, a fast and convenient method using random amplification of polymorphic DNA (RAPD) was established for hybrid discrimination. Hybrids between E. moara ♀ and E. lanceolatus ♂ were identified through specific bands of 387 bp and 433 bp in PRIMER 6.

• Journal of fish pathology
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• v.37 no.1
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• pp.97-110
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• 2024

The Serranidae is high-quality fish species with good meat quality and is traded at high price, and is attracting attention in South Korea as a cultured species that creates high added value. However, the high-density fish farming for mass production increases the risk of mass mortality due to infectious diseases, leading to enormous economic losses. Therefore, in order to safely prevent and protect farmed fish from serious infectious diseases, it is necessary to conduct disease monitoring on a regular basis. In this study, Hyporthodus septemfasciatus, Epinephelus moara, and the hybrid longtooth grouper (E. moara ♀×E. lanceolatus ♂) were collected once a month from fish farm of Garorim and Aquabiotech Co., Ltd for a total of six months, from July to December 2023. We investigated infections of five species of bacterial diseases, including Flavobacterium columnare, six species of viral diseases, including LCDV (lymphocystis disease virus), and parasitic pathogens in grouper farms. As the result, Vibrio vulnificus and V. harveyi were detected in H. septemfasciatus in August, in the case of viral diseases, NNV was detected in H. septemfasciatus from July to August using RT-PCR or PCR. Finally, In the case of parasitic diseases, Tricodina sp. was detected in E. moara and the hybrid longtooth grouper from August to December.

• Journal of Aquaculture
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• v.11 no.4
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• pp.573-580
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• 1998

Red spotted grouper, Epinephelus akaara is distributed in the south and west coasts of Korea. The natural stocks of the fish are decreasing sharply year by uear because of reckless overfishing. This research was carried out to understand general informations on maturation, sex composition and sex-reversals of the fish. Annual fishing uields of red spotted grouper in the castal area of Byonsan Peninsular of Kora decreased over 10% from 1992 to 1994. The main fishing season was from May to July with fishing gear of Hand-lines. Gonadosomatic index (GSI) and condition factor were highest on early and late July, respectively, thus main spawning reriod was assumed from late July to early August. The relationship between total length (X) and body weight (Y) for wild adults was represented as a regression, Y=$0.0169X^{2.9705}$, ($r^2$=0.96). Frequency of sex of wild red spotted gouper showed that the number of female below 38cm in total length was more than that of male, and hermaphrodite mainly occurred from 28cm to 32cm in total length the frequency of male and female were almost same. Also hermaphrodite occurred mainly between 25~29cm. Sex reversal ration of the adults reared in a tank for a year with different sexual compositions revealted that the frequency of female reversed from male was more than that of male reversed from female at 1:1 and 1:2 stocking densities of female and male, respectively. Also, about 20% of female was reversed to male when all females were reared. And the size of the fish reversed to male was larger than that of non-reversed female.

• Ocean and Polar Research
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• v.26 no.4
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• pp.685-688
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• 2004

The morphology of the post-larva of Liopropoma japonicum of the family serranidae is described from one specimen collected off Jeju Island ($32^{\circ}42'N,\;127^{\circ}45'E$) on May 3, 2001. The body is laterally compressed and caudal peduncle deep at 19.4 mm BL. Anus locates at a vertical through posteriormost(8th) dorsal-fin spine. Dorsal fin rays were VIII, 14; anal fin rays III, 10; pectroal fin rays 16; pelvic fin rays I, 5. A caudal fin is rounded. Length of elongate second and third dorsal-fin spines are 499% and 423% of the body length, respectively. A series of 50 sensory pores on body is elongated to caudal fin. Head spination is well developed. Melanophores are moderately large and dense in the head, and are small and rare in teh neck. Being freshly collected, the body color is yellowish-red and tail is semitransparent. The head is yellowish-red and the brain is dark-red.

• Development and Reproduction
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• v.16 no.2
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• pp.121-128
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• 2012

Kisspeptin has been reported to facilitate sexual maturation and ovulation by directly stimulating GnRH neurons via its receptor, GPR54. The KiSS-GPR54 system is playing an important role in the reproduction of several mammalian species. However, little is known about their function in fish. The aim of this study is to understand the physiological function and evolutionary conservation of KiSS-GPR54 system in teleost fish blacktip grouper, Epinephelus fasciatus. In the present study, we have partial cloned KiSS1, KiSS2 GPR54 mRNAs from a brain samples. Tissue distribution analysis using RT-PCR revealed that the KiSS1, KiSS2, GPR54 transcripts were expressed in different tissue. The KiSS-GPR54 system in gonadal of immature and mature stage were analyzed using qRT-PCR. The partial sequence of KiSS1, KiSS2, GPR54 were 232 bp, 304 bp, 613 bp long, respectively. KiSS1, KiSS2, GPR54 mRNAs are shown common expression in the brain. The amount of KiSS1, KiSS2 mRNAs expression were significantly higher in mature stage than immature stage. However GPR54 mRNA expression was higher in immature stage. These results are in good agreement with the hypothesis that KiSS-GPR54 system plays an important role in the regulation of reproductive function in the blacktip grouper.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.499-505
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• 2020

We investigated growth, survival and stress response depending on salinity changes in hybrid grouper (Epinephelus fuscoguttatus ♀×E. polyphekadion ♂, BCG) juvenile. Experiment I (Exp I), the hybrids were stocked at 32 psu and reared for 30 days under decreasing salinity at a rate of 5-7 psu per day (25, 20, 15, 10, 5 psu). Experiment II (Exp II), the salinity was decreased from 32 psu to 5 psu during a period of 24, 48 and 72 h. Experiment III (Exp III), acclimatized BCGs were exposed from 5 psu to decreasing salinity at 0, 1, 2, 3, 4 psu. In the Exp I, 90% survival only in the 5 psu. Growth were 5 and 32 psu had significantly low growth than other treatment. In the Exp II 100% survived by the end of the experiment. The plasma cortisol level was highest in the treatment the salinity rapidly dropped, but all the treatment recovered quickly after 24 h of salinity reduction. In the Exp III, the lower the salinity, the faster the mortality occurred in salinity below 5 psu. It is therefore concluded that the BCGs are highly tolerant of low salinity and the salinity tolerance threshold is 5 psu.

• Korean Journal of Ichthyology
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• v.19 no.3
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• pp.246-252
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• 2007

Two specimens (56.3~61.1 mm SL) of the serranid fish, Chelidoperca pleurospilus and 21 specimens (34.0~93.6 mm SL) of the pinguipedid fish, Parapercis muronis were collected around Jeju Island, southern Korea. C. pleurospilus is characterized by having five dark blotches along lateral line, truncated caudal fin, and scaleless interorbital space. P. muronis is characterized by having five oblique dark bands on body side, five spines on dorsal fin, and no notch between spinous and soft-rayed portions of dorsal fin. We describe these specimens as the first record from Korea, and propose the new Korean name, "Byeol-gak-si-dom" for the former and "Da-seosjul-yang-dong-mi-ri" for the latter.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.2
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• pp.526-536
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• 2015

Changes of oxygen consumption in juvenile giant grouper, Epinephelus lanceolatus were investigated in order to find out the physiological responses associated with freshwater and low salinities acclimation. Salinity changes in this experiment were set as follows; 35 psu (Exp. I) as control, decrease in the manners of $35{\rightarrow}20{\rightarrow}10{\rightarrow}0$ psu (Exp. II), $35{\rightarrow}10{\rightarrow}0$ psu (Exp. III) and $35{\rightarrow}0$ psu (Exp. IV). The average oxygen consumption at $27^{\circ}C$ in Exp. I (control) was $106.9{\pm}0.7mg$ $O_2/kg/h$. In Exp. II, according to the changes of $35{\rightarrow}20{\rightarrow}10{\rightarrow}0$ psu in freshwater acclimation, fish showed the gradual decrease in oxygen consumption as $108.1{\pm}2.1$, $99.6{\pm}2.9$, $74.6{\pm}0.9$ and $62.7{\pm}1.0mg$ $O_2/kg/h$, respectively. The fish in Exp. III also revealed the same tendency as $106.5{\pm}1.3$, $77.0{\pm}1.2$ and $64.7{\pm}1.2mg$ $O_2/kg/h$, respectively. In Exp. IV, fish showed the decreased oxygen consumption from $109.0{\pm}0.9mg$ $O_2/kg/h$ of 35 psu to $71.6{\pm}2.0mg$ $O_2/kg/h$ of 0 psu. Giant grouper is thought to be a diurnal fish species, because the level of oxygen consumption during light period was higher than that during dark period.

• Journal of Life Science
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• v.28 no.6
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• pp.639-647
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• 2018

A new heat shock protein 70 was identified in red-spotted grouper (Epinephelus akaara) based on an expression analysis. The cDNA of red-spotted grouper Hsp70 (designated RgHsp70) was cloned by the rapid amplification of cDNA ends (RACE) techniques. The full-length of RgHsp70 cDNA was 2,152 bp, consisting of a 5'-terminal untranslated region (UTR) of 105 bp, a 3'-terminal UTR of 274 bp, and an open reading frame (ORF) of 1,773 bp that encode a polypeptide of 590 amino acids with a theoretical molecular weight of 64.9 kDa and an estimated isoelectric point of 5.2. Multiple alignment and phylogenetic analyses revealed that the RgHsp70 gene shares a high similarity with other Hsp70 fish genes. RgHsp70 contained all three classical Hsp70 family signatures. The results indicated the RgHsp70 is a member of the heat shock protein 70 family. RgHsp70 mRNA was predominately expressed in the liver, with reduced expression noted in the head-kidney tissues. The expression analysis of different water temperatures (21, 18, 15 and $12^{\circ}C$) for sampled livers revealed that expression gradually increased at $12^{\circ}C$ compared to $21^{\circ}C$. In this study, the effects of water temperature lowering on the physiological conditions were investigated, and the results revealed that novel RgHsp70 may be an important molecule involved in stress responses.

• 지역과문화
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• v.6 no.4
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• pp.47-72
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• 2019

The purpose of this paper is to explore what roles can and should regional culture play in establishing a regional innovation system, which has been recently described as an essential factor for balanced regional development and specialized regional development. In doing so, we first investigated key concepts and discourses regarding regional innovation system and examined the success factors of a regional innovation system. We also explored how the Korean policy makers have developed the nation's regional innovation policy and regional cultural policy in order to understand the policy context and its limitations. After examining the theoretical background, we reviewed the representative cases of regional innovation in Japan, Yufuin and Yubari, to grasp the way in which 'culture' plays its roles in the formation of the regional innovation system. Since culture has a role as a unique sector, such as art and content industry, as well as a community's style of life, this study tried to explore the aspects and ways of how culture can contribute to the establishment of regional innovation systems considering these distinctive levels. In drawing the implications of the case study, we found that special attention is required for the 'process of formation' of regional innovation systems. We also confirmed that the success of the core activities at each stage heavily relies on the culture of the region; in order to fully understand the relations, it is necessary to re-establish the existing concept of culture and cultural policy with a more holistic perspective.