• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.119-123
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• 1979

The cute toxicity test of mercury, cadmium and copper to yellowtail, Seriola quinqueradia, and to rock-bream, Oplegnathus fasciatus, were conducted by static bioassays from 18 July to 27 October, 1978. In the tests, tile least sensitive heavy metals were cadmium to rock bream and copper to yellowtail. The test species were most sensitive to mercury among all the chemicals used. The 24hr-LC 50 value for the yellowtail was 0.11mg/l for mercury, 0.82mg/l for cadmium and 1.03mg/l for copper. While the 48hr-LC 50 value for the rock bream was 1.40mg/l for mercury and 1.73mg/l for copper.

• Journal of fish pathology
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• v.17 no.3
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• pp.199-205
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• 2004

Effects of nitrite, ammonia and hydrogen sulfide on survival of the early developmental stages of Fenneropenaeus chinensis were determined under continuous flow-through system. The 96hr-$LC_{50}$ values of mysis stage were 18.4 mg/L, 0.69 mg/L and 13.5 $\mu{g}/L$ for nitrite, ammonia and hydrogen sulfide, respectively; 28.3 mg/L, 1.23 mg/L and 20.7 $\mu{g}/L$ for post larva stage and 39.8 mg/L, 1.73 mg/L and 28.5 $\mu{g}/L$ for juvenile stage, respectively. The Fenneropenaeus chinensis sensitivity for the three pollutants was in the order of hydrogen sulfide>ammonia>nitrite. The mysis/post larva, mysis/juvenile and post larva/juvenile ratios of nitrite, ammonia and hydrogen sulfide toxicity were >1.5, >2.0 and <1.5 times, respectively, and mysis were found to be more sensitive to pollutants than juvenile in all cases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.190-193
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• 2001

To investigate the effects of the dissolved oxygen concentration (DO) on Scope for growth (SFG) of the manila clam, Ruditapes philippinarum, we measured $LC_{50}$, filtration, respiration, ammonia excretion, and assimilation rates under $23\pm0.5^{\circ}C$ as a function of DO. The $LC_{50}$ of DO for R. philippinarum, was 2.4 mgDO $L^{-1}$. With decreasing DO, filtration and respiration rates of R. philippinarum decreased, while ammonia excretion rate increased, The assimilation rate was $68.2\%$ at 6.5 mgDO $L^{-1}$, decreased to $29.8\~39.3\%$ at 3.5 mgDO $L^{-1}$. R. philippinarum had positive SFG's at the $DO{\geq}2.5mgDO\;L^{-1}$.

• Journal of Marine Life Science
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• v.7 no.2
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• pp.102-112
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• 2022

Crucian carp, Carassius carassius (Weight 39.7±3.1 g, Length 14.8±0.5 cm) were exposed to waterborne nickel at 0, 10, 20, 40, 80 and 160 mg Ni²⁺/l. The lethal concentration 50 (LC₅₀) of C. carassius exposed to waterborne nickel was 117.69 mg Ni²⁺/l. In hematological parameters, RBC counts was significantly increased at 48 hours, whereas a significant decrease was observed at 96 hours. The MCV and MCH were significantly increased in the concentration of 80 mg Ni²⁺/l at 96 hours. The plasma components such as calcium, magnesium, glucose, cholesterol, total protein, AST, ALT and ALP were significantly changed by waterbonre nickel exposure. The results of this study suggest that the nickel exposure to C. carassius affects the survival rates, hematological parameters and plasma components as toxicity

• Journal of fish pathology
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• v.36 no.2
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• pp.349-360
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• 2023

Common carp (Cyprinus carpio) (Weight 23.05 ± 6.98 g, Length 12.65 ± 1.38 cm) were exposed to waterborne nitrite at 0, 50, 100, 200, 400 and 800 mg NO₂ ^-/L for 96 hours. The lethal concentration 50 (LC₅₀) of C. carpio exposed to waterborne nitrite was 398.6 mg NO₂ ^-/L. Hemoglobin, hematocrit and RBC count were significantly decreased by waterborne nitrite exposure. The MCV (mean mean corpuscular volume) (µl), MCH (mean corpuscular hemoglobin) (pg) and MCHC (mean corpuscular hemoglobin concentration) (%) were significantly increased. The inorganic component, plasma calcium, was significantly increased, and the organic components such as plasma cholesterol and total protein were significantly increased showing a similar tendency with calcium. In enzymatic components, the AST and ALT were also significantly increased by nitrite exposure. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of C. carpio.

• Journal of Aquaculture
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• v.16 no.4
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• pp.262-266
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• 2003

In order to develop a method for the cryopreservation of fish embryos, the determination of optimal concentrations of dimethyl sulfoxide (DMSO), ethylene glycol and glycerol as individual cryoprotectants was performed by using the early embryos of black seabream, Acanthopagrus schlegeli. Optimal concentrations of cryoprotectants were assessed in terms of effects on mortality, median lethal concentration and hatching rate of embryos. The mortality of black seabream embryos immersed in cryoprotectants was related to the concentrations of cryoprotectants and immersion times. The toxicity to embryos was lower in order of DMSO, < ethylene glycol, < glycerol. The results from the mortality, median lethal concentration and hatching rate evaluations suggest that DMSO was the most effective cryoprotectant for black seabream embryos followed by ethylene glycol, and suitable concentrations of DMSO and ethylene glycol were 2.0∼2.25M and 1.0∼1.78M, respectively, with 20 minutes of immersion time.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.335-343
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• 2006

Five strains of Korean entomopathogenic nematodes(EPN), steinernematids and heterorhabditids(Steinernama carpocapsae GSN1, Steinernema sp. GSNUS-10, Steinernama sp. GSNUS-14, Heterorhabditis bacteriophora Hamyang, Heterorhabditis sp. GSNUH-1) were evaluated and tried in petri dish, pot, and vegetable greenhouses for environmentally friendly control of beet armyworm, Spodoptera exigua. $LC_{50}$ values of five EPN strains against beet armyworm was different depending on nematode strain and beet armyworm instar. $LC_{50}$ value of Steinernema carpocapse GSN1(GSN1) was 3.8-5.1 infective juveniles(Ijs) in 2nd to 4th instars of beet armyworm. Pathogenicity of five EPN strains against beet armyworm different in nematode strain, concentration, application times, and vegetable species in pot and greenhouse. Steinernema spp. was more effective than Heterorhabditis spp. against beet armyworm. Two or three times of applications of EPN were found to be effective regardless of nematode strain and concentration in pot and greenhouse. ENP showed different reactions on vegetable species. Efficacy of EPN was higher on Chinese cabbage than that on cabbage and kale. GSN1 was one of the most effective nematodes and 100,000 infective juveniles per $m^2$(720,000 Ijs/$7.2m^2=1{\times}10^9$Ijs/ha) resulted in higher mortality in greenhouse.

• Journal of Aquaculture
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• v.5 no.2
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• pp.177-182
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• 1992

Experiments were conducted with goldfish exposed to various levels of mercuric chloride(control group) and mercuric chloride with chitosan (experimental group). Dilutions of these two solutions were made in the concentration ranges 0.6 to 1.0 $mg/{\ell}$ and 1.2 to 2.0 $mg/{\ell}$, respectively. Fifty percent lethal concentration of mercuric chloride($LC_{50}$) for 48 hours with the species was between 0.6 and 0.7 $mg/{\ell}$. Exposure of goldfish to mercury produced a marked, dose-dependent mortality with elevation of concentration (P<0.05). However, at each concentration of mercuric chloride treated with chitosan, mortality decreased significantly compared to control group (P<0.05).

• Korean journal of applied entomology
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• v.51 no.2
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• pp.149-152
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• 2012

The larvicidal activities of Piper nigrum fruit methanol extracts and its constituents against larvae of the diamondback moth, Plutella xylostella, were investigated using the leaf dipping method. Administering the P. nigrum methanol extract resulted in 100 and 97% mortality against diamondback moth larvae at 5.0 and 2.5 mg/mL concentrations, respectively. Larvicidal activities of the P. nigrum fruit-derived piperidine alkaloids, piperine, and N-isobutylamide, as well as pellitorine, guineensine, pipercide, and retrofractamide A against P. xylostella varied according to test compound. Based on the 48 h $LC_{50}$ values, the most toxic compound to diamondback moth larvae was guineensine (0.013 mg/mL) followed by retrofractamide A (0.020mg/mL), pipercide (0.033mg/mL), and pellitorine (0.046 mg/mL). The $LC_{50}$ value of piperine was >0.5 mg/mL.

• Journal of fish pathology
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• v.10 no.1
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• pp.65-72
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• 1997

In the present study, acute toxicity data were obtained for hydrogen sulfide to larvae and adults of blue crab Portunus trituberculatus, white shrimp Metapenacus monoceros and prawn Macrobrachium nipponense under continuous flow through system. The larvae 96hr-$LC_{50}$ values of hydrogen sulfide were 7.3, 9.3 and $9.0{\mu}g/\ell$ for P. trituberculatus, M. monoceros and M. nipponense respectively. The larval sensitivity of the three crustaceans studied for the hydrogen sulfide was in the order of P. trituberculatus> M. nipponense> M. monoceros. The adults 96hr-$LC_{50}$ values of hydrogen sulfide were 42.5, 37.8 and $56.6{\mu}g/\ell$ for P. trituberculatus, M. monoceros and M. ripponense, respectively. The order of toxicity of hydrogen sulfide to adults of the three crustaceans was P. tritruberculatus> M. monoceros> M. nipponense. The larval/adult ratios of hydrogen sulfide toxicity were 5.8, 4.1 and 6.3 for P. trituberculatus M. monoceros and M. nipponense respectively, and larvae were found to be more sensitive to hydrogen sulfide than adults in all cases.