• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.41-47
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• 2012

In the present study, we investigated the characteristic of growth and the tolerance of cold temperature in small yellow croaker and yellow drum. The results shows that the growth of yellow drum were faster than those of small yellow croaker with high food convergency efficiency. In condition factor (CF), the results shows that the values of yellow croaker and yellow drum were significantly higher in September, respectively. In mortality according to cold shock, two fishes was died under $4.7^{\circ}C$ in slow temperature descending test, but was both died under $9^{\circ}C$ in acute temperature descending test.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.474-484
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• 1992

The stock identification of small yellow croaker. Pseudosciaena Polyactis from Mokpo area was carried out using molecular biological methods such as mt-DNA restriction fragment length polymorphism(RFLP) and the N-terminal fragment polymorphism of muscle actin obtained after protease digestion. The entire mt-DNA genomic size from the small yellow croaker at Mokpo area was estimated to be about $16\pm0.2$ Kb. Furthermore, fourteen restriction endonucleases revealed a total of 37 restriction sites to the mt-DNA molecule, however, eight of the fourteen enzymes showed a significant restriction site variation. Six of the enzymes examined produced a single restriction profile for all individuals surveyed, indicating that they don't react on the same mt-DNA obtained from small yellow croaker. The Staphylococcus aureus $V_8$ protease is able to cleave the muscle actin of small yellow croaker and to yield a N-terminal peptide of 26 and 16 KDa, respectively.

• 한국해양학회지
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• v.8 no.2
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• pp.75-77
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• 1973

The catch and effort information for the yellow croaker from the Yellow Sea and the East China Sea during 1964 through 1971 is analyzed on the basis of the generalized production model. The equilibrium catch curve for m=0.2, the best estimate of the skew parameter, is obtained, and the maximum equilibrium catch is shown to be 37,306M/T. It appears that equilibrium catch curve for the yellow croaker is positively skewed and the fishing beyond the maximum of the yield curve will result in a less pronounced decline in yield than would be predicted by the Schaefer model.

• Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.275-281
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• 2012

Yellow croaker Larimichthys polyactis muscle oil was extracted using an environmental friendly solvent, supercritical carbon dioxide (SC-$CO_2$), in a semi-batch flow extraction process. SC-$CO_2$ was applied at temperature $35^{\circ}C$ to $45^{\circ}C$ and $150^{\circ}C$ to $250^{\circ}C$ bar of pressure. The flow rate of $CO_2$ (27.79 g/min) was constant throughout the entire 1.5 h extraction period. The oil extraction yield was influenced by the physical properties of SC-$CO_2$ at different temperatures and pressures. The extracted oil was analyzed by gas chromatography to determine the fatty acid composition. According to our results, the SC-$CO_2$ extracted oil was high in eicosapentaenoic acid and docosahexaenoic acid. In addition, the SC-$CO_2$ extracted oil showed greater stability than n-hexane extracted oil based on the peroxide value and acid value. Thus, the quality of yellow croaker oil obtained by SC-$CO_2$ extraction was slightly higher than that of oil obtained by n-hexane extraction.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.4
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• pp.467-475
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• 2014

This study was performed to estimate optimum fishing mortality (F) and the age at first capture ($t_c$) for small yellow croaker in Korean waters. We first estimated optimum F and $t_c$ using traditional yield-per-recruit (YPR) analysis, and the results were 0.8/year and 2.5 years old, respectively. However, the individual fish price per unit weight of small yellow croaker in Korea increases dramatically by size. Thus, we developed an alternative method, which is called as production value-per-recruit (PPR) analysis. We developed two types of the PPR analysis, that is, the discrete function and the continuous function method. We estimated optimum F and $t_c$ using the two types of the PPR analysis and compared the results. The optimum F and $t_c$ from the discrete function method, were 0.3/year and 5.0 years old, respectively, while those from the continuous function method were 0.5/year and 3.5 years old, respectively. These PPR estimates were much more conservative for the stock management than the traditional YPR analysis, which can prevent the fish stock from the economic overfishing. As a result, the PPR analysis could be more proper approach for stock assessment in the case that the individual fish price per unit weight increases dramatically by size like small yellow croaker in Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.368-377
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• 2014

Small yellow croaker is one of the important stocks in Korean waters. In this study, we conducted sea trials to estimate optimum height of a drift gill net for effective fishing of small yellow croaker. In the trial using existing net which has 9.2m in height, there was 22 species (1,180 fishes, 99.9kg) caught. The catch (in individuals) of small yellow croaker, especially larger fishes (over 22cm in FL), was higher as part of net height is higher, while the number of species bycaught and the catch of those species were higher as part of net height is lower. In the trial using extension net which has 18.4m in height, there was 27 species (2,030 fishes, 151.7kg). It showed same pattern with existing net in the section I to III, however, in the section IV which is over 13.8m of net height, the catch sharply decreased. The number of species bycaught and the catch of those species using extension net were also same as results using existing net. It showed that section III (9.2-13.8m) where is upper-middle part of the net has caught most of catch and large fishes having over 22cm in length. Through these results, it is judged that the setting depth of the net where is 4.6-13.8m above the sea bottom is the best to reduce bycatch and catch much more large size fishes, and the catch per net is proportional to filtering area of net. Therefore the Fisheries Resource Management Act (the clause 1, article 10) on the amount of usage for offshore drift gill net need to be considered not only length of a net but also net height.

• Fisheries and Aquatic Sciences
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• v.24 no.2
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• pp.63-77
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• 2021

The aim of this research was to investigate different factors, including cryoprotective agents (CPAs), diluents, dilution ratios, equilibrium times, freezing rates, and thawing methods to optimize cryopreservation protocols for large yellow croaker (Larimichthys crocea). The parameters evaluated were sperm motility, sperm activity index (SAI), survival rate, and DNA damage. Different types of CPAs, such as dimethyl sulfoxide (DMSO), propylene glycol (PG), ethylene glycol (EG), methanol, and glycerol, were tested for sperm preservation. The highest motility, SAI, and survival rate were observed when EG was used. Different diluents such as Stein's solution, Hank's balanced salt solution, marine fish Ringer's solution, artificial seminal plasma (ASP) of small yellow croaker, and Cortland solution were investigated. The highest post-thaw motility was observed upon using ASP as the diluent. Different concentrations of EG were then mixed with ASP to identify the optimal EG concentration. Experimental results showed that the motility (70.33 ± 1.20%), SAI (5), and survival rate (78.30 ± 0.42%) of post-thaw sperm were optimum when 10% EG and ASP were used as the CPA and diluent of cryopreservation, respectively. Post-thaw sperm motility was high at equilibration times below 150 s and at an optimum dilution ratio of 1:1 (sperm: CPA + diluent) and was not significantly different compared with fresh sperm motility. The freezing rate was found to be slow below -10℃/min. The thawing temperature of 45℃ was identified as ideal. The percentage of tail DNA in post-thaw sperm at 10% EG and ASP was also investigated and was found to have more significant DNA damage than that in fresh sperm but significantly lower damage than that in post-thaw sperm at EG concentrations of 5%, 15%, and 20% (p < 0.05). The cryopreservation protocols obtained in this study will be useful in large yellow croaker hatcheries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.933-938
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• 1994

A study was amino acid contents by heating conditions of mackerel, pacific saury , yellow croaker, and brown sole investigated. In fresh fishes, total amino acid contents showed higher amount in brown sole and yellow croaker, than those of pacific saury and mackerel. The amino acid contents among the tested samples were higher Glx , leucine, lysine and arginine in order. During heating of samples the amino acid contents decreased. There appeared to be a proportional relationship of the heating temperature to decrease of amino acid. The amino acid contents of steamed samples significantly decreased than those of others. During warming and rewarming samples after storage at 4$^{\circ}C$ for 24 hours , amino acid contents slightly decreased.

• Journal of fish pathology
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• v.35 no.1
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• pp.135-140
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• 2022

In this study, we determined the cause of a disease outbreak in small yellow croaker(Larimichthys polyactis) in Jeju island. The major external signs in the dead fish were hemorrhage of the skin. Vibrio harveyi were isolated from a few fishes and viruses were not detected from the diseased fish. However, flukes were confirmed on the skin and we conducted molecular identification and phylogenetic analysis of the isolated parasites. The obtained 28S rRNA sequence of our specimen(Accession No. OM333244) showed the highest homology with Neobenedenia girellae, while the COI sequence of our specimen showed the highest homology with N. melleni. Further sequence analysis with other genes and morphological observation are necessary for accurate identification.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.232-248
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• 2004

In order to utilize fisheries resources under a joint management scheme with adjacent nations, as well as detecting of fishing grounds, the factors which influence yellow croaker (Pseudosciaena polyactis) in Korean waters were studied using historical catch per unit effort and oceanographic data. The main fishing ground near Cheju Island was located along the thermal front formed between the Yellow Sea Bottom Cold Water (YSBCW) and northward moving warm current. When the YSBCW (index temperature: $10^{\circ}C)$ strongly extended southward, the fishing condition were worse than average. Especially, low temperatures greatly influenced stow net fisheries, which were operated in the deep water layer The concentration and dispersal of fishing ground and catch coincided with oceanographic features and the seasonality of water masses.