• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.75-84
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• 2014

To determine a suitable dietary protein/lipid (CP/CL) ratio in the early juvenile stages of hybrid porgy ($F_1$), female red sea bream (RSB) ${\times}$ male black sea bream, five diets with various CP/CL ratios-60/7, 55/12, 51/17, 46/23, and 41/28-were prepared and provided to juveniles in triplicate. At the smaller juvenile stage, $F_1$, weighing 0.32 g, a significantly higher specific growth rate (SGR) and feed efficiency (FE) were seen with 60/7 and 55/12 diets. However, in RSB weighing 0.26 g, SGR and FE were higher with the 60/7 diet than the other diets at $21^{\circ}C$. At the larger juvenile stage, $F_1$, weighing 3.7 g, there was no significant difference in SGR or FE among the diets, but RSB weighing 4.0 g fed 60/7, 55/12, and 51/17 diets had higher SGR and FE than 46/23 and 41/28 diets at $24^{\circ}C$. Moreover, survival and apparent nutrient retention of $F_1$ at both stages were significantly higher than those in RSB. These results indicate that both $F_1$ and RSB weighing ca. 0.3 g require a higher dietary CP/CL than those weighing ca. 4 g. Additionally, $F_1$ in both trials showed the suitability of a lower dietary CP/CL than RSB, indicating that mass production of $F_1$ juveniles will be more economical than RSB.

• 한국관개배수회지
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• no.48
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• pp.11-19
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• 2011

• Journal of fish pathology
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• v.25 no.3
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• pp.221-229
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• 2012

Hybrid of red seabream (Pagrus major) and Japanese red seabream (Pagrus major) grew rapidly from to August (WT $19.7^{\circ}C{\sim}24.0^{\circ}C$) while black seabream (Acanthopagrus major) did from September to October (WT $19.9{\sim}23.0^{\circ}C$). Survival rate of hybrids (85.5%) was a significantly higher than those of the other fish species (20%). Green liver syndrome were observed in black sea bream and Japanease red seabream but did not in hybrids. Microcotyle tai infected 0~90% in hybrid, 20~100% in red seabream, 10% in black sea bream and 20~100% in Japanese red seabream but no significant difference was found among each fish species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.4
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• pp.365-371
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• 2003

The reared fries of black sea bream, Acanthopagrus schlegeli were released in Gamak Bay and initial adaptation to the environment was evaluated. Thirty thousand fries were marked with magnetic tag, released and recaptured and its stomach content were analysed; the neighboring zooplankton, beuthic algae and other young fishes were investigated. The fries were released on July 30, 2001 in summer season. Water temperature of surface and bottom were $24^{\circ}C\;and\;21^{\circ}C,$ respectively. $Chlorophyll\;\alpha$ content was 4.5 ${\mu}g/L$ with high primary production. Salinity was $32.0-32.5\%_{\circ}.$ Water depth of releasing site was about 30 m. The sea jungle was formed at the first point of releasing and it kept the fries for about 3 days in the bay with plenty of food organisms within 5 m depth. Stomach analysis of the fries revealed that real feeding started from the 15 days after releasing and full feeding took place after the tenth day.

• Journal of fish pathology
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• v.20 no.2
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• pp.99-108
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• 2007

Vibrio harveyi, one of the major causal agent of vibriosis, affects a diverse range of marine vertebrates and invertebrates over a wide geographical area. The organism is synonymous with Vibrio carchariae, which is also known as a fish pathogen. The aims of this study were to investigate the characteristics of the pathogenic non-luminous V. harveyi and the luminous V. harveyi. And V. harveyi isolates were examined the pathogenicity to the black rockfish, Sebastes schlegeli. Both strains of V. harveyi showed haemolytic activity, and the survival rate of non-luminous V. harveyi FR 2 was higher than other strains in the skin, gut mucus and fresh serum of olive flounder, Paralichthys olivaceus and black rockfish, Sebastes schlegeli, respectively. The virulence of non-luminous V. harveyi FR 2 was higher than that of luminous V. harveyi VIB 391 in the intraperitoneally infected black rockfish. In conclusion, the present study revealed that the pathogenicity of V. harveyi FR 2 isolated from marine fish was higher than that of V. harveyi VIB 391 isolated from shrimp for black rockfish. It was suggested that the pathogenicity of V. harveyi on the black rockfish was related with bacterial luminescense.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.276-283
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• 2011

The growth and tolerance for water temperature and salinity were compared among red sea bream Pagrus major (RSB) black sea bream Acanthopagrus schregeli (BSB) and their hybrid ($F_1$), female RSB ${\times}$ male BSB. The growth of the $F_1$ fish did not differ until 27 days after hatching (dAH), after which the most rapid growth was observed until approximately 300 dAH, followed by RSB and BSB. However, the RSB had out grown the $F_1$ fish by approximately 303 dAH. By 480 dAH, the RSB were largest, followed by the $F_1$ and BSB groups. The tolerances for high and low water temperature were significantly different for each species and growth stage. The largest tolerance spectrum was observed in the BSB group, and the tolerance spectrums gradually decreased with increasing final body weight. During the salinity tolerance trials, all of the species started to die following transfer into freshwater (0 psu). BSB showed the highest survival rate when kept in fresh water for an average of 29.9 hours, while the $F_1$ fish were more tolerant than the RSB fish. The fish were increasingly tolerant to fresh water and changes in water temperature as they grew, while the size of the temperature spectrum remained unchanged but shifted to a lower temperature range with growth. Our results demonstrate that $F_1$ performed well in terms of growth compared to parental fish, with higher temperature and salinity tolerances than RSB, and is thus suggested to be a suitable aquaculture species for Korea and northeast China.

• Journal of Aquaculture
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• v.21 no.1
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• pp.7-12
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• 2008

Toxicity of ten commercial disinfectants(hydrogen peroxide, sodium hypochlorite, chlorine dioxide, povidon iodine, formaldehyde, glutaraldehyde, quaternary ammonium compounds(QAC), didecyl dimethyl ammonium chloride(DDAC), ortho-dichlorobenzene, and copper sulfate) was measured by chinook salmon embryo-214 cell line and three fish species: flounder Paralichthys olivaceus, black rockfish Sebastes pachycephalus, and black sea bream Acanthopagrus schlegelii. The $LC_{50}$ levels of 24 hours acute toxicity with the ten disinfectants were tested in three species of fish. Effectiveness of ten chemical disinfectants were varied by each chemical as well as by species. Hydrogen peroxide showed the higest activity at 201, 269, and 139 ppm in the flounder, the black rockfish, and black sea bream, respectively. DDAC showed the lowest activity at 2.1, 1.0, and 1.5 ppm in the flounder, the black rockfish, and black sea bream, respectively. The highest variation was observed in copper sulfate by both the chemicals and the species.

• Animal cells and systems
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• v.14 no.1
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• pp.37-44
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• 2010

Black sea bream, Acanthopagrus schlegelii, is a commercially important fish in Korea. As a preliminary investigation into the effect of hatchery rearing for stock enhancement, we examined genetic diversity between wild and farmed black sea bream populations from Jeju using six microsatellite markers. High levels of polymorphism were observed between the two populations. A total of 87 different alleles were found at the loci, with some alleles being unique. Allelic variability ranged from 8 to 22 in the wild population and from 7 to 17 in the farmed one. Average observed and expected heterozygosities were estimated at 0.87 and 0.88 in the wild sample. The corresponding estimates were 0.83 and 0.86 in the farmed sample. Although a considerable loss of rare alleles was observed in the farmed sample, no statistically significant reductions were found in heterozygosity or allelic diversity in the farmed sample, compared with the wild one. Significant genetic heterogeneity was found between the wild and farmed populations. These results suggest that more intensive breeding practices for stock enhancement may have resulted in a further decrease of genetic diversity. Thus, it is necessary to monitor genetic variation in bloodstock, progeny, and target populations and control inbreeding in a commercial breeding program for conservation. This information may be useful for fisheries management and the aquaculture industry.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.2
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• pp.123-138
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• 2019

The hat on the back of the upper jacket in Scythian, in of northern region surrounding the Black Sea, is described as a typical woolen hood, but until now has been overlooked in Korean costume studies. The purpose of this study is to analyze the hat on the upper jacket in Scythians and to recognize the meaning of the hat. A further purpose is to complete the basic framework of research concerning the Scythian costume by adding the part that was overlooked previously As for the research method, we collected literature, previous research results, the exhibition catalog, and the related artifacts for analysis. The literature was collected at the German Archaeological Research Institute. The analysis of artifacts was based on data collected by the researchers at the Heremitage Museum in Russia and data was taken by the staff of the Heremitage Museum. The conclusions of this study are as follows: Among the artifacts in the northern region of the Black Sea, it was perviously believed that Scythians status was signified by the wearing of hat-tops. Regardless of age, warriors and knights all wore upper jackets with hats, so it appears that the people who are active wore upper jackets with hats. On the other hand, it was assumed that the royal family, who wore ornamented, colorful, and decorative hats were not observed to have worn upper jackets with hats, and therefore did not require a hat. Therefore, it is considered that the hat in the Scythian society was a costume element emphasizing practicality, not necessarily a class symbol.

• Journal of fish pathology
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• v.25 no.3
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• pp.231-241
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• 2012

Diagnostic monitoring in fish farms with land-based tanks and netpen cases were conducted in eastern, western, southern and Jeju island of Korea during summer of 2007~2011. In total, 2413-fish samples of 4 marine fish species were tested for the detection of bacteria and parasite. Fish species tested were olive flounder (Paralichthys olivaceus), black rockfish (Sebastes schlegeli), red sea bream (Pagrus major), pacific white shrimp (Litopenaeus vannamei). During the diagnostic monitoring from 2007 to 2011, the infection rates by single infection of bacterial or parasitic pathogens were relatively higher than the mixed infections. The main bacterial pathogens in olive flounder, black rockfish and pacific white shrimp were Vibrio spp. (V. harveyi, V. ichthyoenteri, Vibrio sp.). The main bacterial pathogens in red sea bream were also Vibrio sp. and Photobacterium damselae subsp. damselae. The main parasitic pathogens were both Miamiensis avidus and Trichodina sp. in olive flounder, Microcotyle sebastes in black rockfish, Microcotyle tai in red sea bream and Zoothamnium sp. in pacific white shrimp.