• Journal of Aquaculture
• /
• v.13 no.1
• /
• pp.69-78
• /
• 2000

Bioactivity growth and survival rte of yolk sac larvae in cultured black seabream (Acanthopogrus schlegeli) red seabream (Pagrus major) and olive flounder (Paralichthys olivaceus) to 5 different concentration (0, 25, 50, 75 and 100%) of water soluble fraction (WSF) of Kuwait crude oil were studied. The 75% and 100% of WSF concentration influenced negatively on the length growth of larvae in each species so the growth rates of total length in the concentration of WSF were significantly lower than those of control. The high concentration (50%, 75%, and 100%) of WSF influenced negatively not only on the swimming frequency and speed but also on the morphological abnormality of larvae. Red seabream larvae showed the highest rate of abnormality by WSF among the tested fishes. The fish larvae exposed during pre-and post-hatch (egg and larval stages) and during post-hatch (larval stage only) to the WSF were significantly influenced on their survival rate. The larvae of red seabream were more sensitive to WSF than those of black seabream and olive flounder. The survival rates of larvae exposed to higher concentration (50%, 75%, and 100%) of WSF were significantly lower than those of the control but those of the 25% group were not.

• Journal of fish pathology
• /
• v.21 no.3
• /
• pp.167-174
• /
• 2008

Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

• Environmental Analysis Health and Toxicology
• /
• v.25 no.3
• /
• pp.197-205
• /
• 2010

The ecotoxicological effects of two antibiotics, fenbendazole and lincomycin, were observed in the harpacticoid copepod Tigriopus japonicus s.l. collected from tidal pools in the southern coast of Korea. Fenbendazole had a significant effect on the survival rates (p < 0.05), delay of copepodite emergence, and urosome size (p < 0.05). Lincomycin, on the other hand, had no significant influence on these environmental indicators. However, our analysis of morphological abnormalities in T. japonicus s.l. showed that lincomycin was more effective than fenbendazole in causing deformities. The pattern of deformity was diverse, with fused segments, and loss or addition of setae in the swimming legs. All of these patterns appeared as a result of relatively low concentrations of this antibiotic (0.3, $1\;{\mu}g\;L^{-1}$). We report here patterns of morphological abnormality in T. japonicus s.l. exposed to antibiotics, and suggest their possible application in ecotoxicological monitoring.

• Korean Journal of Environmental Biology
• /
• v.35 no.2
• /
• pp.128-133
• /
• 2017

To determine the optimum water temperature (a temperature which minimizes metabolic activities and stress in fish) for long distance transportation of red-spotted grouper (Epinephelus akaara), by evaluating the behavior, survival and physiological and hematological responses to variable water temperature conditions (9, 12, 15, 18 and $21^{\circ}C$) for 48 hours. Fish exposed to $9^{\circ}C$ died at 48 hours exposure, but those exposed to 12, 15, 18 and $21^{\circ}C$ treatment groups all survived. Fish in the 15, 18 and $21^{\circ}C$ exposure groups exhibited normal swimming, while those exposed to $12^{\circ}C$ were observed to be stationary at the bottom of the tank. The plasma cortisol and glucose concentration were higher in fish exposed to $12^{\circ}C$ than at other temperature conditions. The fish in the 12 and $15^{\circ}C$ groups had significantly higher hematocrit (Ht) and hemoglobin (Hb) than those in the 18 and $21^{\circ}C$ groups (P<0.05). Levels of aspartate aminotransferase (AST), $NH_3$ and osmolality showed a pattern similar to the levels of plasma cortisol, while alanine aminotransferase (ALT) and total protein did not significantly vary among the experimental groups. These results indicate that the optimum water temperature for long distance transportation of the red-spotted grouper is $15^{\circ}C$.

• Korean Journal of Ichthyology
• /
• v.29 no.1
• /
• pp.22-31
• /
• 2017

To find out the stress response and wound healing of surgical incisions, we analyzed the change of stress hormone and the healing process in far eastern catfish, Silurus asotus. The survival rate of the clove oil (1,000 ppm) anesthesia group after surgery was about 90% in 3~42 days, while no anesthesia group showed about 74%. Thus, the survival rate after anesthesia group was higher than that of the no anesthesia group. The plasma cortisol concentration of the clove oil anesthesia group was higher than that of the no anesthesia group (P<0.05). In addition, the plasma glucose concentration of clove oil anesthesia group was higher than that of the no anesthesia group (P<0.05). The plasma lactic acid concentration of clove oil anesthetized group was higher than that of the not anesthetized group (P<0.05). On the 14 days and 28 days after surgery, there were still stitching fiber of suture and swimming behavior was not active. On the 35 days after surgery, trace of the suture has almost disappeared on the outside of the fish. Finally, 42 days after surgery, stitching fiber was not visible, and the sutured wounds were distinctly recovered. The results of this study showed that the anesthesia group showed higher survival rate and received less postoperative stress than that of the no anesthesia group. Surgical wound healing in the catfish of this study was shown to be successful when using anesthetics.

• Journal of Fisheries and Marine Sciences Education
• /
• v.29 no.2
• /
• pp.422-435
• /
• 2017

Intermolt periods, growth rates, survival (%) and relative growth of the megalopa larvae of Portunus trituberculatus (Miers, 1876) were studied up to the crab 7th stage for 160 days in the 3 different temperature groups in which each has 60 larvae. The higher the water temperature was the shorter the intermolt period was in each crab stage. In addition, a deviation of intermolt periods was shown as few as the water temperature gets higher. The intermolt period in the 7th crab stage was $29.8{\pm}3.26$ days in the experimental group at the room temperature, $45.2{\pm}3.89$ days at the temperature of $17^{\circ}C$, and $25.6{\pm}2.23$ days at the temperature of $27^{\circ}C$, respectively. The survival (%) of larvae of P. trituberculatus (the crab 7th stage) is the highest in the group at the room temperature: However, they showed 15% at the temperature of $27^{\circ}C$ and 10% at the temperature of $17^{\circ}C$. All the groups were shown the similar relative growth, but significant differences appeared in some comparison. The sizes (mean growth of carapace width) of the crabs in the group at the temperature of $27^{\circ}C$ reached 5.01~25.45 mm length (it is the longest among the groups) from the crab 1th to the crab 7th stage. However, the sizes (mean growth of carapace width) of room temperature were 4.99~22.26 mm and the size of crab in the group at the temperature of $17^{\circ}C$ reached 4.8~17.26 mm, The sizes (mean growth of carapace length) of the crabs in the group at temperature of $27^{\circ}C$ reached 2.88~13.56 mm, However, the size of the crab in the group at the room temperature showed 2.88~12.34 mm, while in the group at temperature of $17^{\circ}C$, their average growth of carapace length were 2.51~8.03 mm. The growth rates of larvae of P. trituberculatus (from the crab 1th to the crab 7th stage) were changed with the increase of the instar stage, however their changes showed irregular.

• Korean Journal of Environmental Biology
• /
• v.40 no.3
• /
• pp.247-254
• /
• 2022

To investigate the tolerance limit and critical thermal maximum (CTM), behavioral responses of wild goldeye rockfish Sebastes thompsoni according to exposure to high water temperature were observed using a continuous behavior tracking system. As a result, behavioral index (BI) of S. thompsoni in each temperature (20.0, 25.0, and 30.0℃) showed a significant difference (p<0.05) when compared with the value measured in a stable condition of 15.0℃. The activity level of S. thompsoni exposed to 25.0℃ decreased sharply after 20 hours. Their rest time at the bottom of experiment chamber increased, and their normal swimming and metabolic activities were disturbed. In addition, at a high water temperature of 30.0℃, S. thompsoni reached the limit of resistance and showed a sub-lethal reaction of swimming behavior, with energy consumption in the body increased and all test organisms died. In conclusion, the eco-physiological response of S. thompsoni to water temperature varied greatly depending on the fluctuation range of the exposed temperature and the exposure time. In addition, the tolerance limit of S. thompsoni to high water temperature was predicted to be 25.0-30.0℃. The maximum critical thermal that had a great influence on the survival of this species was found to be around 30.0℃.

• Journal of fish pathology
• /
• v.25 no.1
• /
• pp.47-58
• /
• 2012

Behavioral and physiological responses of juvenile red seabream (Pagrus major) to different concentrations of ethanol were investigated. No swimming and no reaction to touching by a wooden stick was observed at 0.6% ethanol group in behavioral response, and survival rate was 100% after 5 hours of treatment. Red blood cell count, hematocrit and hemoglobin levels in plasma were not significantly different among all groups. AST activities in plasma significantly decreased as ethanol concentration increased. On the contrary, ALT activities in plasma significantly increased as ethanol concentration increased. Cortisol level in plasma was the lowest in 0.6% ethanol group. Glucose levels in plasma increased significantly when ethanol concentration increased more than 0.4%. Oxygen consumption of fish in 0.6% ethanol seawater was constantly lower than that of fish in control seawater from 2 hours after the exposure to ethanol seawater until the end of experiment.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.41 no.4
• /
• pp.241-247
• /
• 2005

The aim of this study was to develop a trawl escapement device which can improve the survival rate of young fishes passed through trawl codend. The sea experiments according to the bar space of the device and bar materials were carried out to decide the bar space and device materials in Korean southern sea and off Cheju island. Stainless pipes and MC bars were used to test the efficiency of escapement device materials. Although escapement rates of MC bar for main species were a little higher compare with stainless pipe, the efficiency of device for stainless pipe was better than MC bar. Escapement devices of sort-K type and grid panel type were also compared. Escapement rates of redlip croaker(Pseudosciaena polyactis), blackthroat seaperch(Doederleinia berycoides) and finespotted flounder (Pleuronichthys cornutus) showed 61.7%, 2.0% and 2.7% on the sort-x type and 69.9%, 1.1% and 2.0% for the grid panel type but the difference was little. Fishes under 20mm head width and fishes which swimming speed is so slow compared with body length could not go through well the device. Escapement rates according to the bar space were estimated using grid panel type. The rates of redlip croaker(Pseudosciaena polyactis) for the bar space of 20mm, 25mm, 35mm were increased as 60.3%, 61.0% and 77.8%, and 9.8%, 16.4% and 45.6% for horse mackere1(Trachurus japonicus), respectively.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.36 no.4
• /
• pp.13-22
• /
• 2020

Recent abnormal climate has increased the frequent of heavy rains and floods, and over 100 people have been killed in the last decade caused by these. In the midst of severe flood disasters, safety education to learn how to respond and evacuate them has become important. The purpose of this study was to analyze the needs and effective education types for the flood disaster school safety education. This study shows Analysis the current state of school safety education based on the 7 standards of school safety education, especially in disaster safety categories through the survey of secondary school teachers and students. And a desirable form of flood safety education was derived by analysis of awareness of flood disaster safety education and their educational needs. More than 70% of teachers and students hoped for a experience-based flood disaster safety education, they wanted to learn once a year, one hour from a safety education specialist in experience facilities. As for the contents of the training, they wanted to experience evacuation in the event of flood disaster, and also wanted education related to survival swimming. The most necessary thing for the establishment of experience-based disaster safety education was the expansion of experience facilities.