• 한국어병학회지
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• 제37권1호
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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.

• 한국어류학회지
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• 제31권4호
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• pp.235-240
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• 2019

자바리와 대왕자바리 2종을 대상으로 MS-222 농도 및 수온에 따른 마취효과 실험을 수행하였다. 농도는 100, 150, 200 그리고 250 ppm을, 수온은 18, 22, 26 그리고 30℃에서 마취 및 회복시간을 조사하였다. MS-222 농도와 수온이 높아질수록 마취시간이 짧아지는 경향을 보였으며, 회복시간은 농도와는 비례하지만 수온과는 반비례하는 경향을 보였다. 회복시간은 22℃ 이하에서는 큰 차이가 없었다. 자바리의 최적 마취조건은 회복시간이 가장 짧은 30℃와 100 ppm, 대왕자바리의 경우 30℃ 150 ppm이 회복시간이 100 ppm과 유의적으로 차이가 없으면서 마취시간은 유의하게 짧아 가장 적합했다. 이원배치분산분석 결과 자바리와 대왕자바리의 종 간 유의한 차이가 있었으나, 종과 농도 그리고 종, 농도, 수온에 대한 상호작용 효과는 없었다.

• 한국수산과학회지
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• 제53권4호
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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.

• 한국수산과학회지
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• 제53권4호
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• pp.572-576
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• 2020

As grouper aquaculture production intensifies worldwide, hybrids are increasingly produced to induce heterosis of traits such as rapid growth and strong environmental adaptability. In this study, we compared the morphological characteristics of a hybrid grouper to those of its parent species Epinephelus moara and E. lanceolatus. The coefficients of external and skeletal traits evaluated using soft X-rays did not differ significantly among groups; however, several patterns were detected among measured traits. The body depth (BD), length of caudal peduncle (LCP), and pre-anal fin length (PAL) of the hybrid were the same as those of E. moara, whereas the pre-pectoral fin length (PPL) and interorbital width (IOW) of the hybrid were the same as those of E. lanceolatus. Traits that did not differ significantly among the three groups included pre-dorsal fin length (PDL), pre-ventral fin length (PVL), length of anal fin (LAF), and length of dorsal fin (LDF), whereas the depth of caudal peduncle (DCP) and snout length (SNL) showed intermediate traits, and eye diameter (ED) was significantly smaller in the hybrid. Therefore, intermediate traits such as DCP and SNL and specific traits such as ED may be used as indices for hybrid classification.

• 한국수산과학회지
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• 제37권5호
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• pp.414-422
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• 2004

To infer phylogenetic relationships among Epinephelus species inhabiting coastal regions of Korean peninsula, mitochondrial cytochrome b genes from 9 species belonging to the subfamily Epinephelinae were PCR-amplified, cloned and sequenced. Aligned cytochrome b sequences of 10 species containing one additional sequence from GenBank were 1,140 base pairs in length, including 439 variable and 330 parsimony informative sites. The cytochrome b genes of 10 species, as other vertebrates studied to date, exhibit unequal base compositions: an entirely low G content ($15.2{\pm}0.3{\%}$on average) and almost equal T, C and A contents ($29.3{\pm}0.8{\%},\;30.7{\pm}1.0{\%},\;and\;24.8{\pm}0.5{\%}$ on average, respectively).In third codon positions, transitional substitutions especially between Epinephelus species and outgroup species are almost certainly saturated or near saturation. Phylogenetic analyses were performed with sequence data from 8 Epinephelus species and 2 outgroup species (Cephalopholis urodela and Vaviola louti) by using distance-based (neighbor-joining and minimum evolution) and parsimony-based (maximum parsimony) methods. The results showed that the monophyly of the genus Epinephelus was supported by relatively high bootstrap values. However, phylogenetic relationships among E. areolatus, E. moara, E. septemfasciatus, and Epinephelus sp were poorly resolved. Within the genus Epinephelus, three resolved monophyletic groups were found: clade 1 included E. akaara and E. awoara;, clade 2 included E. fasciatus and E. merra; and clade 3 included E. akaara, E. awoara, E. fasciatus, E. merra, E. areolatus, E. moara, E. septemfasciatus and Epinephelus Sp.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.31-32
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• 2003

• 한국수산과학회지
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• 제55권2호
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• pp.129-136
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• 2022

The nutrient composition of the muscle of the hybrid grouper (Epinephelus fuscoguttatus×E. lanceolatus, HG) and the hybrid longtooth grouper (E. moara×E. lanceolatus, HLG) was measured as a function of body weight in this study. The crude protein and lipid levels in HG were 21.0-21.2 g/100 g and 1.9-3.4 g/100 g, respectively. HLG contained 20.6-20.7 g/100 g protein, and 3.9-5.5 g/100 g crude lipid. The total amino acid contents of HG were 18,829.7-18,980.2 mg/100 g and that of HLG was 17,793.7-19,293.7 mg/100 g. The mean saturated fatty acid content was 0.61-1.09 g/100 g for HG and 1.27-1.77 g/100 g for HLG. Monounsaturated and polyunsaturated fatty acid levels were 0.59-1.02 g/100 g (Monoene), 0.67-1.11 g/100 g (Polyene) in HG, which were lower than the 1.21-1.78 (Monoene), 1.22-1.69 g/100 g (Polyene) found in HLG. The highest mineral content (K and P) of HG was 510.13-517.05 mg/100g and 231.59-247.67 mg/100 g, while that of HLG was 518.81-523.59 mg/100 g and 257.51-248.84 mg/100 g, respectively. In conclusion, there is potential for expanding the commercial utilization of HG and HLG as food resources as they are both nutrient-rich.