• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.30 no.4
• /
• pp.273-282
• /
• 1994

This paper describes about the behavior of the lseraeli carp (Cyprinus cartio. body length 43cm) and the Red seabream (Chrysophrys major. body length 35cm) aquacultured by telemetry techniques. The telemetry system consists of a pinger of 50kHz, three omni-directional hydrophones and ultrasonic receivers, a single board computer for the signal processing, two RF transceivers for the data communication, and a personnel computer. Those fish tagged the pingers were tracked by the LBL method, and its location was calculated by the hyperbolic method. The average speed of the lsraeli carp was about 1.0 times of the body length in a farming water tank (24$\times$24$\times$1m), and the Red seabream 1.3 times of the body length in a farming raft (10$\times$10$\times$5m). A variation of the speed of the lsraeli carp was higher than the other one.

• Development and Reproduction
• /
• v.21 no.1
• /
• pp.63-69
• /
• 2017

On the 15 days after hatching, the larvae was 4.24-5.10 mm (mean $4.66{\pm}2.18mm$) in total length, and the fins of the membrane started to develop into a fan shape and the melanophore was deposited upper the alimentary canal of the abdomen and on the bladder. At 35 days after hatching, the post-larvae formed a branch-shaped melanophore on the head part with a total length of 6.98-12.5 (mean $9.35{\pm}1.71$) mm, formed on the upper and lower parts of the caudal part, formed on the upper and lower parts of the caudal part, and deposited under the head part and abdomen. At 40 days after hatching, the juvenile was 11.3-18.1 (mean $14.9{\pm}1.53$) mm in total length.

• Korean Journal of Ichthyology
• /
• v.19 no.2
• /
• pp.173-177
• /
• 2007

A series of experiments were conducted to compare the effects of various diluents and cryoprotectants on the motility and survival rate in cryopreservation of the red seabream, Pagrus major sperm. Sperm was efficiently cryopreserved using 300 mM glucose as a diluent. Two cryoprotectant, dimethyl sulfoxide (DMSO) and glycerol, were added to 300 mM glucose to formulate the extenders at concentrations between 5% and 30% by volume for freezing. The highest post-thawed sperm motility and survival rate were obtained with 10% DMSO.

• Fisheries and Aquatic Sciences
• /
• v.14 no.2
• /
• pp.130-137
• /
• 2011

Visual stimuli of nets, which affect fishing selectivity, vary by twine diameter, color, and material under different light conditions and visual geometries. In this study, two cylindrical model codends of two mesh sizes, 28 and 43 mm, were made of high-contrast, dark brown polyethylene (PE) netting twine and low contrast, light-blue polyamid (PA) monofilament twine. Each model codend was filled with juvenile seabream and set in the water channel of a light-blue circular tank under a flow speed 0.8 m/s for 30 min. Light conditions were set to relatively bright, dim, and dark. The resulting retention rates of juvenile seabream were 15-35% lower for the low-contrast codend with PA monofilament than for the high contrast PE twine netting under bright and dim light conditions, while no difference was observed under dark conditions. The effects of mesh size and netting contrast on the retention rate were dependent on the light level, while the retention rate due to netting contrast was independent of mesh size. Therefore, low-contrast nets in the codend could help to reduce juvenile bycatch by disturbing the orderly optomotor response.

• 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.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.

• Proceedings of the Acoustical Society of Korea Conference
• /
• spring
• /
• pp.233-236
• /
• 2000

The acoustical response of fish depends on size and physical structure na, most important, on the presence or absence of a swimbladder. Acoustic scattering models for swimbladdered fish represent a fish by an ideal pressure-release surface having the size and shape as the swimbladder. Target strength experiments of red seabream (Chrysophrys major) have been conducted using 38 (split-beam), 120 (split-beam) and 200kHz (dual-beam) frequencies. At each start of each experiment, the live fish are placed in the cage at the surface, then the cage is lowed to about $4{\cal}m$ depth where it remains during the measurements. To test the acoustic models, predictions of target strength based on swimbladder morphometries of 10 red seabream offish total length from $103{\cal}mm{\;}to{\;}349{\cal}mm$ ($3 <$TL/\lambda$ < 45)are compared with conventional target strength measurements on the same, shock-frozen immediately after caged experiments. X-ray was projected along dorsal aspect to know the morphological construction of swimbladder. and fish body. At high frequencies, Helmholtz-kirchhoff(HK) approximation would greatly enhance swimbladdered fish modeling. Sound scattering model [HK-ray approximation model] for comparison to experimental target strength data was used to model backscatter measurements from individual fish. The scattering data can be used in the inverse method along with multiple frequency sonar systems to investigate the adequacy of classification and identification of fish

• Journal of fish pathology
• /
• v.28 no.3
• /
• pp.157-164
• /
• 2015

The effect of dietary carrot extract on skin pigmentation and non-specific immunity of red seabream was evaluated in a six-week feeding trial compared to that of astaxanthin. Fish were fed different experimental diets supplemented with three levels of carrot extract (30, 100, and 300 mg ${\beta}$-carotene/kg diet or CE30, CE100, and CE300), 100 mg astaxanthin/kg diet (AXT100), or a diet without supplement as control for 6 weeks. Our results revealed that the specific growth rate and feed conversion rate were not significantly (p>0.05) affected by carrot extract or astaxanthin supplementation for 6 weeks. After 3 weeks of feeding, the dietary carrot extract significantly (p<0.05) influenced the redness ($a^*$) and hue ($H^*{_{ab}}$) of fish skin. CE300 showed the highest $a^*$ and the lowest $H^*{_{ab}}$, suggesting that carrot extract increased the redness of skin color. However, after 6 weeks of feeding, dietary carrot extract significantly (p<0.05) increased the values of yellowness $b^*$ at all three levels. In contrast, AXT100 significantly (p<0.05) increased the values of $a^*$ but decreased the value of $H^*{_{ab}}$. Only CE300 significantly (p<0.05) increased the serum lysozyme activity. These findings suggest that dietary carrot extract can be utilized as a natural feed additive to improve skin pigmentation and health condition of fish.

• Ocean and Polar Research
• /
• v.26 no.4
• /
• pp.551-557
• /
• 2004

Polymorphism of the lipoprotein lipase (LPL) gene which plays an important role in regulation of lipid deposition was analysed in two red seabream (pagrus major) populations (KF4, cultured KORDI line, n=100 : JPN, imported from Japan, n=100). We amplified a DNA fragment (1,091 bp) including the exon 2 region of the LPL gene, and conducted PCR-RFLP analysis using MspI and AluI. The PCR products were also sequenced. Two alleles (A and B) were found in MspI digestion and Sve alleles (A, B, C, D and E) in AluI digestion. The sequenced data revealed four nucleotide substitutions including one transversion at the MspI recognition site (nt 2,235, $C{\rightarrow}10$) and three transitions at the AluI recognition sites (nt 1,721, $A{\rightarrow}G;$ nt 2,319, $C{\rightarrow}T;$ nt 2,319, $T{\rightarrow}C$). Among them, substitutions at the nt 2,235 and 2,319 sites which are located in the exon 2 were proved to be silent point mutations. MspI polymorphism resulted in 3 genotypes, and the allele frequency was significantly different between the two fish populations, KF4 and JPN. In the case of AluI polymorphism, the 5 alleles (A, B, C, D, E) comprised 12 genotypes of the 5 alleles. KF4 population, alleles D and I were specific to the LPL gene Polymorphisms would be useful DNA markers for red seabream population.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.40 no.3
• /
• pp.182-188
• /
• 2004

It has been, in general, known that the catching efficiency of a trammel net is better than that of a gill net because of the variability of catch species and size. In this stidy, A fishing gear test was carried out to analyze the catching efficiency of the gill net and the trammel net on the coast of Geomun-do of southern Korean waters and fish school aggregation was also investigated using a underwater video camera. CPUE of the gill net was 49.2% higher than the trammel net but fish species was 34.5% lower where there was no difference on the significance level of 5% by ANOVA test. Main catch species caught by the gill net were red seabream(Pagrus major) and triggerfish(Aluterus monoceros), skate ray(Raja Kenojei) and red seabream for the trammel net, and the average body length of red seabream was shorter than the trammel net. It was thought that the reason of higher catch in the gill net than the trammel net was a fish school which can be caught easily by gill net and the size of population was suitable for the gill net.