• 한국수산과학회지
• /
• 제57권3호
• /
• pp.253-261
• /
• 2024

This study investigated the digital color profiles corresponding to different maturity stages and levels of brown croaker Miichthys miiuy specimens collected from the Southern Sea of South Korea. Maturity stages were determined using photomicrographs of ovarian developmental phases, which were compared with digital color values. Brown croaker specimens ranged from 24 to 81 cm in standard length; mature ovaries were predominantly observed in specimens that exceed 40 cm in length. Monthly ovary color values were primarily concentrated in the 1st and 4th quadrants, with both a^* and b^* values falling within a range of ±15 centered on the origin. Similarly, the testes color values were predominantly situated in the 4th quadrant, with a^* and b^* values ranging from -5 to 15 and 10 to 14, respectively. While the color values of the mature and spawning stages overlapped within a narrow range, distinguishing between them required both the color value and monthly color value distribution to be considered. Thus, this study underscores the efficacy of digital color measurements for assessing brown croaker gonad maturity, and provides more quantitative insights compared to subjective visual assessments by humans.

• 수산해양기술연구
• /
• 제50권4호
• /
• pp.467-475
• /
• 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.

• 한국식품조리과학회지
• /
• 제11권1호
• /
• pp.77-82
• /
• 1995

Boiled, broiled, deep fried, pan fried 등의 방법으로 조리된 조기와 돼지고기의 50% methanol 추출물에 S9 mix를 첨가한 군, S9 mix를 첨가하지 않은 군, 그리고 nitrite를 처리한 군을 Salmonella typhimurium TA98과 TA100으로 Ames test를 실시하여 돌연변이원 형성을 검토한 결과는 다음과 같다. 1. S9 mix를 첨가하지 않은 조기와 돼지고기는 original weight 0.0125 g과 0.1 g사이의 농도 구간에서 돌연변이 원성을 보였다. 2. S9 mix 첨가시 조기와 돼지고기의 돌연변이원성은 모든 농도 구간에서 S9 mix를 첨가하지 않은 경우보다 2∼5배 정도 증가하여 간접 돌연변이원이 존재함을 확인하였다. 3. TA98과 TA100에 대한 돌연변이원성은 모든 조리법에서 조기보다 돼지고기가 더 높았고, 특히 pan fried법의 경우 S9 mix의 첨가시 돌연변이원성이 매우 높게 나타났다. 4. 조기와 돼지고기의 모든 조리법에서 nitrite 처리시 TA98과 TA100 모두 돌연변이원성이 증가하여 직접돌연변이원임을 나타냈고, 특히 TA100보다 TA98에서 돌연변이원성이 더 높은 것으로 나타났다.

• 한국어류학회지
• /
• 제24권1호
• /
• pp.41-47
• /
• 2012

본 연구는 조기류(참조기, 수조기)의 양식생물학적 기초자료를 확보하고자 육상수조에서의 성장 특성 및 저수온 노출에 대한 영향을 조사하였다. 1년 사육기간동안 수조기가 참조기에 비해 성장이 빨랐고, CF는 모두 9월에 가장 높게 나타났으며, DFI는 모두 9~10월에 최대값을 보인 후 낮아졌다. 사료계수는 참조기가 2.20, 수조기가 1.34였다. 완만한 수온 하강에 대한 영향은 참조기와 수조기 미성어 모두 $4.7^{\circ}C$ 이하에서 폐사가 발생하였으며, 조기류 월동의 임계수온은 $9^{\circ}C$로 나타났다.

• 한국수산과학회지
• /
• 제25권6호
• /
• pp.474-484
• /
• 1992

황해서식 참조기(Pseudosciaena polyactis)에 대한 계군을 분석하기 위한 연구의 일환으로 우선 황해의 목포 연근해에서 채집된 참조기의 난자와 근육으로부터 mt-DNA와 근육 actin을 추출하였다. 난자의 경우 mt-DNA를 추출한 뒤 제한효소로 처리하여 절편다형현상을 관찰하였으며 근육 actin의 경우 단백질 분해효소(Staphylococcus aureus $V_8$ protease)로 처리하여 N-terminal 절편의 다형현상을 각각 관찰하였다. Mt-DNA의 genome 크기는 약 $\16\pm0.2$ Kb였고 전체 절편수는 37개였으며 사용된 20개의 제한효소 중 8개의 제한효소만이 3개 정도의 절편을 보이므로써 유의성을 관찰할 수 있었다 한편 근육 actin을 Staphylococcus aureus $V_8$단백질 분해효소로 처리하였을 때 N-terminal 부위에서 26 KDa 및 16 KDa의 분자량을 갖는 특이절편을 관찰할 수 있었다.

• 생명과학회지
• /
• 제16권1호
• /
• pp.88-94
• /
• 2006

본 연구에서 넙치와 조기의 원산지를 판별하기 위한 도구로 RAPD PCR 방법의 가능성을 확인하였다. 넙치는 한국의 주문진 자연산, 통영 양식산, 거제 양식산 그리고 북한 자연산을 실험에 사용하였다. 조기는 한국산과 중국산을 사용하였다. 넙치의 RAPD 패턴에서는 뚜렷하고 일관성이 있는 진단용 띠들을 쉽게 찾을 수 있었다. 조기의 경우에는 유전적인 이질성으로 인하여 각 개체의 RAPD 패턴에서는 일관성이 있는 진단용 띠를 찾기 어려웠지만 각 원산지별로 얻은 RAPD 패턴에서는 가능성이 있는 진단용 띠들을 찾을 수 있었다.

• 수산해양기술연구
• /
• 제50권3호
• /
• pp.368-377
• /
• 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
• /
• 제24권2호
• /
• pp.63-77
• /
• 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.

• 한국수산과학회지
• /
• 제55권5호
• /
• pp.721-729
• /
• 2022

We investigated the ecological characteristics and biomass of white croaker Pennahia argentata population in the South Sea of Korea using catch data from Danish seins fishery and biological data from 2018 to 2020. Survival rate (S), which was estimated using Pauly method (1984) was 0.361 per year, and the instantaneous coefficient of total mortality (Z) was 1.019 per year. The instantaneous coefficient of natural mortality (M) and that of fishing mortality (F) were estimated as 0.351 and 0.668 per year, respectively. At first capture, age was estimated to be 1.19 years and length at this age was 18.7cm. The annual biomass was estimated with a biomass-based cohort analysis using annual catch data between 1997-2020 in Korean water. The biomass of the white croaker declined sharply from 4,000 tons in 1999 to the lowest level of approximately 1,000 tons in 2004. Post 2004, the biomass started to increase gradually and reached approximately 7,000 tons. The amount of resources was 35.7%, 34.8%, and 16.5% at age one, two, and three years, respectively, and 86.9% of all captured white croaker individuals belonged to the age group of 1-3 years.

• 한국식품영양과학회지
• /
• 제23권6호
• /
• pp.933-938
• /
• 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.