• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.28 no.3
• /
• pp.373-381
• /
• 1995

Oxygen consumption of marine fishes according to different water temperatures, fish population densities and body weights was measured in the respiratory chamber for the following six species: the olive flounder Paralichthys olivaceus, the tiger puffer Takifugu rubripes, the rockfish Sebastes schlegeli, the sea bass Lateolabrax Japonicus, the red seabream Pagrus major and the black seabream Acanthopagrus schlegeli. Also the lethal concentration of dissolved oxygen in them was determined. Oxygen consumption in each fish species increased as the water temperature increased. The relationship between the oxygen consumption rate $(Oc,\;ml/kg{\cdot}\;hr)$ and the water temperature (T,$^{\circ}C$) for each species appeared as the following equations demonstrate; olive flounder: Oc=34.0515T-339.5987 $(r^2=0.9730)$, tiger puffer: Oc=34.4941T-479.8732 $(r^2=0.9483),$ rockfish: Oc=44.7970T-634.2627 $(r^2=0.9718),$ sea bass: Oc=26.1488T-318.0633 $(r^2=0.9316),$ red seabream: Oc=61.1020T-722.8926 $(r^2= 0.9805),$ black seabream: Oc=75.1460T-947.9370 $(r^2=0.9392).$ The of gen consumption of fish with different population densities decreased as the number of fish increased. As the body weight of the olive flounder increased, the mass-specific oxygen consumption decreased. The relationship between oxygen consumption and body weight (W; g) was expressed as Oc=2532.0268W-0.6565 $(r^2=0.9229)$. The levels of lethal dissolved oxygen in the olive flounder, rockfish, tiger puffer and red seabream were 0.66, 0.79, 0.75 and 1.36 m1/1, respectively.

• Journal of Aquaculture
• /
• v.20 no.3
• /
• pp.147-153
• /
• 2007

The present study was performed to evaluate sitological quality of the cultured and wild river puffer, Takifugu obscurus. Proximate composition, the content of extractive nitrogen, the content of nucleotides and their related compounds, total and free amino acid, and fatty acids were analysed and sensory evaluation in the muscle of the river puffer were compared. The cultured river puffer had a higher moisture content compared to the wild fish, while there was no significant difference in crude lipid, crude protein and ash contents. Nucleotides and their related compounds including ATP, ADP, AMP, IMP, HxR and Hx were detected. The result from analyzing ATP-related compound showed difference in total content by wild and cultured river puffer, and IMP content that had largest influence upon the savory taste of sliced raw fish, was higher in the cultured fishes than wild ones. Breaking strength level of the wild river puffer was higher than that of the cultured fish. High levels of C16:0 and C18:0 were shown in all samples and -3 polyunsaturated fatty acid content were not different between the cultured and wild river puffers (P>0.05). Total 17 amino acids were detected in the samples, and most of the samples had high contents of glutamic acid, aspartic acid, lysine and leucine and low contents of cystine, histidine, methionine and tyrosine. The result from surveying free amino acid content of wild and cultured river puffer showed difference in content, but generally taurine and lysine content for the whole free amino acid held the most part. There was no significant difference in texture, flavor and overall acceptance score between the cultured and wild fishes (P>0.05).

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.24 no.4
• /
• pp.144-149
• /
• 1988

The purpose of this study is to find the light intensity which induced maximum gathering rate and to observe the variation of the gathering rate both in daytime and tat night by using Striped puffer, Fugu xanthopterus (Temminck et Schlegel). An experimental tank(360L$\times$50W$\times$55H cm) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Eight artificial light sources were prepared by combination of three light bulbs (10W, 60W, 100W) and eight filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 60 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 298.56 lux (188.44-444.96 lux) at daytime and 298.56 lux (188.44-444.96 lux) at night. The variation of the gathering rate of fish in illumination time was increasing trend fluctuately and did not show any distinctive difference between day and night.

• Journal of fish pathology
• /
• v.18 no.1
• /
• pp.99-103
• /
• 2005

This study investigated the distribution of scuticociliates in the intestine, spleen, kidney, testis, brain, pericondrial bone and muscle layer of the tiger puffer, Takifugu rubripes, infected with scuticociliates. Scuticociliates were infiltrated in the connective tissues of the outer layer of the intestine, spleen, kidney, testis, brain, pericondrial bone and muscle layer. In brain, membranous tissue and optic lobe cortex separation were accompanied by the infection of scuticociliates. Other internal tissues and organs did not show any lesions expect for heavy deposition of hemosiderin in spleen.

• Journal of Fisheries and Marine Sciences Education
• /
• v.29 no.2
• /
• pp.447-452
• /
• 2017

A closely associated set of characteristics was analyzed using both classical and truss dimensions to discriminate sexual dimorphism between spawning season and non spawning season in grass puffer, Takifugu niphobles. In non-spawning season, $1{\times}10/Ls$ of classical dimension was significantly different between male and female (P<0.05). In spawning season, $1{\times}9/Ls$ and $1{\times}10/Ls$ of classical dimension, $3{\times}8/Ls$, $3{\times}9/Ls$, $3{\times}10/Ls$, $4{\times}8/Ls$, $4{\times}9/Ls$ and $8{\times}9/Ls$ of truss dimension and $7{\times}9/HL$ of head part dimension were significantly different between male and female (P<0.05). The results of this study may be useful as basic information of other fish species to compare the change of sexual dimorphism between spawning season and non spawning season.

• Korean Journal of Food Science and Technology
• /
• v.6 no.3
• /
• pp.177-184
• /
• 1974

File fish Navodon modestus was dehydrated in cabinet type hot-sir drier at $48-50^{\circ}C$ for 11 hours and also yellowfin puffer Fugu xanthopterum was dried in open air at $26-28^{\circ}C$ for 30 hours. Nucleotides and their related compounds were collected by extraction with cold perchloric acid and their amounts were determined by anion exchange column chromatography. The contents of ADP, IMP, ATP and hypoxanthine in fresh file fish muscle were 22.9, 12.1, 4.9, and 3.2 ${\mu}mole/g,$ dry wt. respectively. AMP and inosine were 0.9 ${\mu}mole/g,$ dry wt. equally. In fresh yellowfin puffer muscle, the contents of ADP, ATP, AMP, inosine and hypoxanthine were 25.6, 2.4, 1.6, 0.3, 0.6, and 0.4 ${\mu}mole/g,$ dry wt. respectively. In the case of file fish, ADP and ATP tended to degrade rapidly during hot-air dehydration. The contents of IMP were decreased slightly while AMP and inosine were increased. And another case of yellowfin puffer, ADP also tended to degrade rapidly during sun drying while AMP, IMP, inosine and hypoxanthine were increased. Especially, in both case of file fish and yellowfin puffer, inosine was increased twenty five and thirty five times during drying respectively.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.53 no.2
• /
• pp.218-230
• /
• 2020

The single anatomical attribute that has the greatest influence on acoustic scattering from fish is the presence or absence of a swimbladder. This study examined the effect of removing the gas from the swimbladder on the broadband backscattering characteristics of six species of swimbladdered fish: striped beakperch Oplegnathus fasciatus, black scraper Thamnaconus modestus, dark-banded rockfish Sebastes inermis, goldeye rockfish Sebastes thompsoni, black rockfish Sebastes schlegeli and panther puffer Takifugu pardalis. Before and after removing the gas from the swimbladder, the species-specific, frequency-dependent backscattered echo signals from anaesthetized individuals of each fish species were measured at approximately 1° intervals spanning a 90° aspect angle range from -45° (head down) to +45° (head up) using a broadband echo sounder operating at 100-200 kHz. The relationship between the wavelength-normalized backscattering cross section (σ/λ²) and fish length (L/λ) was calculated for each species. The average σ/λ² value for the six fish species at a L/λ range of 19.79-25.85, with a mean of 22.89, was reduced by approximately 52.3% when the gas was removed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.4 no.4
• /
• pp.298-304
• /
• 1999

Toxic effect of landfill leachate on the larvae and juvenile stage of the river puffer fish, Takifugu obscurus, were investigated in order to assess severity of environmental impact of leachate effluent on the general population of estuarine fishes. A short-term toxic experiment was designed to test both laboratory hatched larvae and juveniles (5, 10 and 15 mm in length) and in-situ juveniles (30 and 45 mm in length) using the leachate concentrations between 0 and 16%. Lethal concentrations of 50% mortality ($LC_{50}$) were observed using Spearman-karber Method. 24hr-$LC_{50}$ appeared at the leachate concentrations ranging from 3.03 to 8.57%, 48hr-$LC_{50}$ at 2.73 to 6.21 %, 72hr-$LC_{50}$o at 2.45 to 5.53%, and 96hr-$LC_{50}$ at 2.38 to 4.93%, respectively. Leachate concentrations between 0.69 and 1.51% induced 96hr-$LC_1$. Respiratory frequency was significantly affected even at low leachate concentrations between 0.5 and 1.0% (P < 0.05). These results suggest that the leachate effluents may cause a harmful impact on the physiology of river puffer fish, especially for younger cohorts.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.39 no.6
• /
• pp.447-453
• /
• 2006

Toxicity of two species of puffer fish, Takifugu porphyreus and Takifugu rubripes, collected from coastal regions of Korea, was determined using a mouse bioassay, In T. porphyreus, the proportion of toxic specimens containing ${\ge}$ 10 MU/g was 58.3% for the ovary, 32.6% for the skin, 12.0% for the gallbladder, 11.6% for the liver and intestine, and 9.3% for the fin; no toxicity was detected in the muscle and testis using the mouse bioassay. The highest toxin levels were 531 MU/g in the liver, 253 MU/g in the intestine, 136 MU/g in the gallbladder, 118 MU/g in the skin, 116 MU/g in the ovary, and 108 MU/g in the fin. The skin, which is used for human consumption, showed significantly high toxicity with an average of $11{\pm}3\;(mean{\pm}SE) MU/g$. Takifugu porphyreus toxicity also exhibited remarkable regional variation. In T. rubripes, the proportion of toxic specimens was 25.0% for the ovary, 15.8% for the liver, 11.1% for the gallbladder, and 5.3% for the fin and intestine; no toxicity was detected in the muscle, skin, or testis. Among the organs, the highest toxin levels were 228 MU/g in the ovary, followed by 112 MU/g in the liver, 28 MU/g in the gallbladder, 18 MU/g in the intestine, 11 MU/g in the fin, and 8 MU/g in the skin. Thus, we found acceptable toxin levels in the edible muscle and skin of T. rubripes and in the muscle of T. porphyreus. However, the skin of T. porphyreus, which showed significantly high toxicity, requires special attention when used for human consumption.

• Journal of Food Hygiene and Safety
• /
• v.27 no.1
• /
• pp.37-41
• /
• 2012

The current standard for testing tetrodotoxin (TTX) in foodstuffs is the mouse bioassay (MBA) in Korea as in many other countries. However, this test suffers from potential ethical concerns over the use of live animals. In addition, the mouse bioassay does not test for a specific toxin thus a sample resulting in mouse incapacitation would need further confirmatory testing to determine the exact source toxin (e.g., TTX, STX, brevotoxin, etc.). Furthermore, though the time of death is proportional to toxicity in this assay, the dynamic range for this proportional relationship is small thus many samples must be diluted and new mice be injected to yield a result that falls within the quantitative dynamic range. Therefore, in recent years, there have been many efforts in this field to develop alternative assays. High performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) has been emerged as one of the most promising options. A LC-MS-MS method involves solid-phase extraction (SPE) and followed by analysis using an electrospray in the positive ionization mode and multiple reactions monitoring (MRM). To adopt LC-MS-MS method as alternative standard for testing TTX, we performed a validation study for the quantification of TTX in puffer fish. This LC-MS-MS method showed good sensitivity as limits of detection (LOD) of $0.03{\sim}0.08{\mu}g/g$ and limits of quantification (LOQ) of $0.10{\sim}0.25{\mu}g/g$. The linearity ($r^2$) of tetrodotoxin were 0.9986~0.9997, the recovery were 80.9~103.0% and the relative standard deviations (RSD) were 4.3~13.0%. The correlation coefficient between the mouse bioassay and LC/MS/MS method was higher than 0.95.