• 한국양식학회지
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• 제10권2호
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• pp.189-197
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• 1997

A series of short (8 hours) and long term (96 hours) exposure studies was conducted on a laboratory scale to evaluation (1) the threshold concentrations of petroleum hydrocarbon in seawater which can lead to tainting problems in yellow tail (Seriola quinqueradiata) and (2) the time to recover (depuration period) once the tainting has occurred. The water-soluble fraction (WSF) of crude oil was prepared by stirring the oil with cold seawater. The main component of the WSF were low-boiling aromatics, although these were only al small proportion of the starting oil. From the sencory evaluation it was concluded that the threshold hydrocarbon levels in seawater which will impart a taint in yellow tail fillets within a 8-hour exposure period (short exposure period) are in the range of 0.4 to 1.0 ppm and within a 96-hour exposure period (long exposure period) are in the range of 0.2 to 0.5 ppm. Depuration trials were carried out with WSF from crude oil. The fish were exposed for 48 hours to concentration of 2.5 ppm hydrocarbons. After 48-hour exposure period, the fish were allowed to depurate in fresh, uncontaminated seawater. Depuration time for these fish was 10 days. The taste panelists were able to detect the contaminated fillets very easily while the depurated fish could not be distiguished from the control.

• 한국양식학회지
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• 제18권1호
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• pp.37-44
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• 2005

해산어류의 담수순화 양식을 위한 기초자료를 얻고자, 감성돔을 재료로 하여 담수와 해수에서 90일간 사육하였을 때, 어체의 생리상태를 스트레스, 삼투압조절, 성장 및 생존율 측면에 서 조사 비교하였다. 스트레스 측면에서 담수돔과 해수돔의 혈장 cortisol농도의 경우 60일째까지 유의한 차이가 없었으며, 실험종료시에는 각각 12.6$\pm$5.0 ng/ml, 4.5$\pm$2.9 ng/ml로 담수돔이 해수돔보다 높았지만 안정시의 농노에 포함되는 것으로 나타났다. 삼투압조절 측면에서 담수돔과 해수돔의 삼투질농도의 범위는 각각 346.7$\pm$4.6$\~$356.5$\pm$2.1 mOsm/kg, 350.0$\pm$2.0$\~$351.0$\pm$2.6 mOsm/kg으로 차이가 나타나지 않았으며, 또한 아가미 조직의 손상이나 세포의 괴사도 관찰되지 않았다. 성장 및 생존율 측면에서 실험종료시 담수돔과 해수돔의 전장은 각각 17.0$\pm$1.3 cm, 16.1$\pm$0.8, 체중은 각각 88.2$\pm$22.0 g, 69.4$\pm$11.8 g, 생존율은 각각 $80.2\%$, $73.7\%$로 담수돔에서 높게 나타났으나 유의한 차이는 인정되지 않았다. 또한 증중률 등의 성장관련 요인과 체성분의 조성면에서도 담수돔과 해수돔간의 차이가 없는 것으로 나타났다.

• 한국수산과학회지
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• 제55권6호
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• pp.894-902
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• 2022

This study investigated the effects of photoperiod (NL 12L:12D and LL 24L:0D) and body sizes (30 g and 50 g) on parr-smolt transformation, post-smolt growth and blood properties in the off-season parr-smolt stage of Atlantic salmon reared in a recirculating aquaculture system (RAS). Potential off-season salmon smolt were reared in a freshwater RAS for 80 days and then all experimental fish were transferred to seawater. In both LL groups (LL-30 and LL-50), we recorded and increase in specific growth rate and reduction in feed conversion, although there were no significant difference in body size. The values of osmolality, and serum Na⁺, Cl^- and cortisol concentrations in the LL groups were maintained at lower levels than in NL group fish, and LL group fish were observed to recover to the pre-seawater adaptation state more rapidly than those in the NL group. ID chips were inserted in all smolts reared in freshwater. These fish were subsequently transferred to full-strength seawater and thereafter individual growth rates were monitored for 120 days. The results indicated that compared with smolt reared under natural photoperiodic condition, 24 h lighting in freshwater contributed to enhancing post-smolt specific growth rate in seawater.

• 수산해양교육연구
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• 제27권1호
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• pp.253-261
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• 2015

The chemical water quality and fish assemblage of Dong Stream to assessment of environmental improvement after discharge seawater were investigated from July to December 2013. BOD and DO were significantly different between before and after discharge seawater, while pH and SS did not significant. A total of 11 fish species, 218 individuals and 10,525.1g were collected. Dominant fish species were Mugil cephalus, Konosirus punctatus, Acanthogobius flavimanus and Leiognathus nuchalis which account for 77.5% of total individuals collected, and they were estuarian species. Peak number of species and individuals, and biomass occurred in September, whereas diversity index were highest in November. The water ecosystem of Dong Stream have been changed estuarian environment. As a result of stream assessment on water quality and ecosystem, water quality have been improved as 'III' grade. These results suggested that stream restoration policies such as drain pipes maintenance, management of pollution sources and riverbed dredging to improve environment and recover habitate of Dong Stream were need for set up and establishment of regular monitoring system.

• 한국양식학회지
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• 제19권1호
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• pp.14-18
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• 2006

해산어류인 감성돔의 담수사육에 따른 어육을 평가하기 위하여 근육의 경도와 강도를 조사하였으며, 설문조사를 통한 어육의 외관, 질감, 맛 및 냄새를 분석하였다. 또한 수익성분석을 위해 치어 및 육성어를 10개월간 양식하여 각각의 순수익(률)을 산출하였다. 담수사육 감성돔 근육의 경도 및 강도는 각각 $9210{\pm}1215g/cm^2,\;30693{\pm}6355g/cm^2$로 해수사육의 $9987{\pm}1893g/cm^2,\;31931{\pm}6549g/cm^2$보다 다소 낮았으나 유의한 차이는 없었다. 또한 설문조사한 결과, 어육의 외관, 질감, 맛 및 냄새에서도 담수 및 해수사육한 감성돔사이에 차이가 없는 것으로 나타났다. 감성돔 치어 및 육성어를 담수에서 10개월간 양식하였을 때 순수익(률)은 각각 24,000,000원(30.0%), 53,870,000원(36.9%)으로 나타났다.

• 한국수산과학회지
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• 제46권1호
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• pp.46-52
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• 2013

After an outbreak of viral disease in an aquafarm, release of virus (es) from infected fish into environmental seawater has been suspected. In the present study, we utilized a negatively charged membrane (HA type) as an efficient method for concentration and detection of fish pathogenic viruses, specifically, megalocytivirus and viral hemorrhagic septicemia virus (VHSV) present in field-collected seawater samples or inoculated into seawater artificially. Positively charged viruses adsorbed onto the negatively charged membrane and were eluted with 1 mM NaOH (pH 10.5) following rinsing with 0.5 mM $H_2SO_4$ (pH 3.0). Megalocytivirus and VHSV particles isolated using anegatively charged HA membrane from seawater inoculated with each virus at a concentration of 10 viral particles/mL were of sufficient quantity to show positive results in atwo-step PCR (or RT two-step PCR); however, despite it being negatively charged, a cellulose acetate (CA) membraneshowed negative results. In quantitative PCR, the detection limits of the HA membrane for megalocytivirus and VHSV in seawater were 1.20E+00 viral particles/mL and 1.22E+01 viralparticles/mL, respectively. The calculated mean recovery yields from 1 L seawater spiked with known concentrations of megalocytivirus and VHSV particles were 28.11% and 23.00%, respectively. The concentrate of a 1-L sample of culturing seawater from the aquatank of flounder suffering from VHSV showed clear positive results in PCR when isolated with an HA, but not a CA, membrane. Thus, viral isolation using an HA membrane is a practical and reliable method for detection of fish pathogenic viruses in seawater.

• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.118-125
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• 2000

Lipid classes and fatty acid compositions of eight species of wild and cultured seawater fish in Korea were investigated. Total lipid (TL) contents of wild and cultured fish were $2.64\pm1.88\%$ and $5.42\pm1.76\%$, respectively, except for rockfish and striped beakperch. Non-polar lipids (NL) in all fish samples comprised approximately $84\%$ of the TL content. The proportion equation of NL content to TL content was y=0.9296x-0.4468 $(R^2=0.98l2, p<0.001)$. The most abundant NL class was triglyceride. The prominent fatty acids in all fish samples were 16: 0, 18: 1(n-9), 22 : 6(n-3) (docosahexaenoic acid, DHA), 16: 1(n-7), 20 : 5 (n-3) (eicosapentaenoic acid, EPA), 18 : 0 and 18 : 1(n-7). The polyunsaturated fatty acid (PUFA) group was the richest among the total fatty acids (TFA). DHA and EPA were comprised of approximately $85\%$ of n-3 PUFA. There was a positive correlation between TFA content and n-3 PUFA content; y=0.292x-0.0055 $(R^2=0.9349, p<0.001)$. The n-3 PUFA content of the cultured fish was approximately twice as much as that of the wild fish. Therefore, cultured fish were proven to provide better sources of n-3 PUFA if compared to wild fish.

• 한국식품위생안전성학회지
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• 제16권3호
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• pp.241-246
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• 2001

서울시를 비롯한 6개 도시의 음식점과 활어를 판매하는 어시장 등에서 활어조에 사용하는 해수에 대하여 병원성 비브리오균의 분포, 이화학적특성 및 위생지표세균 등 환경인자와의 관계를 비교하였다. 시험해수에서 전염병균인 Vibrio cholerae O1은 전혀 검출되지 않았고, V. parahaemolyticus는 가장 빈번한 검출되었는데 검출율은 69.2%이었다. 그리고 V. vulnificus 및 V. cholerae non-O1 등 병원성 비브리오균이 검출된 활어조의 해수는 그렇지 않은 해수에 비하여 수온과 탁도는 높았고, 염분과 pH는 낮았으며 생균수, 대장균군 및 분변계 대장균이 휠씬 높게 검출되어 이러한 환경인자들과의 관련성이 시사되었다.

• 한국어병학회지
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• 제25권1호
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• pp.47-58
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• 2012

에탄올 0.6% 해수에 5시간 동안 침지한 참돔 치어는 유영행동을 멈추었으며 외부의 물리적 자극에도 반응하지 않는 상태에 도달하였다. 이 농도구에서 생존율은 100%였으며 RBC, hematocrit, Hb 수치는 다른 그룹과 유의한 차이를 보이지 않았다. 혈장 코티졸 농도 또한 0.6% 에탄올 농도에서 가장 낮은 값을 나타냈다. 그러나 0.8% 이상의 에탄올 해수에 침지한 실험어는 심한 스트레스 반응과 높은 폐사율을 보였다. 참돔 치어를 0.6%의 에탄올 해수에 침지시키고 매시간 산소소비량을 측정한 결과, 에탄올해수에 침지된 실험어는 실험개시 2시간 후부터 종료 시까지 지속적으로 일반해수에 침지된 실험어보다 적은 산소를 소비하였다. 이상의 결과들은 에탄올에 의해 유도된 취기효과가 마취제의 마취효과와 비슷하였으며, 5시간 침지 시 혈액성상, 행동반응, 생존율, 산소소비율 등을 종합하여 볼 때, 0.6% 이하의 에탄올 농도가 참돔치어에게 안전한 농도이며, 0.8% 이상에서는 독성으로 작용할 수 있음을 보여준다.

• 한국양식학회지
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• 제10권4호
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• pp.435-438
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• 1997

전기분해를 이용한 해수의 암모니아성 질소 및 대장균 제거에 효과적이었다. 암모니아의 제거효율은 전류의 세기가 클수록, 반응 시간이 길수록, 극판간격이 좁을수록 증가하였다. 해수내 250/100 m\ell$의 대장균은 모든 실험 조건에서 검출되지 않아, 살균 목적으로 전기분해가 매우 효과적이었다. 암모니아의 제거 효율은 잔류 염소의 농도에 따라 증가하였다. 암모니아의 제거 효율과 잔류 염소와의 관계는 다음과 같다.$NH_4^+-N(%)=4cdotlog[Residual\;chlorine(mg/\ell)+28(r=0.892)$