• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.5
• /
• pp.526-535
• /
• 2001

The gametogenesis, reproductive cycle, frequency distribution of egg diameter and fecundity of spotted sea bass Lateolabrax maculatus were investigated by histological observation. The samples were collected at Goheung, Jeonam from December 1996 to November 1997. Gonadosomatic index (CSI) was appeared less than 1.0 in female and male from December to July and began to increase from August and reached the maximum values of female 7.50 and male 2.98 in October. Hepatosomatic index (HSI) was appeared annual maximum value of female 1.97 and male 1.64 in March and then decreased from April. The annual reproductive cycle of this species can be divided into four successive stages: growing stage (July to August), maturation stage (September to October), ripe and spawning stage (October to November) and degeneration and resting stage (November to July). According to the frequency distribution of egg diameter, the development mode of egg was not seperated, formed one mode for the maturation and spawning season, The individual absolute fecundity ranges from $1,726,242\~17,822,576$ eggs, and individual relative fecundity ranges from $29,458\~214,730$ eggs in total length (cm) and $938\~3,363$ eggs in body weight (g). Female and male of L. maculatus were matured when total length were over 50.1 and 45.1 cm, respectively.

• Journal of Marine Life Science
• /
• v.9 no.1
• /
• pp.22-32
• /
• 2024

The purpose of this study was to determine the effect of external biologger attachment methods on the blood parameters and attachment efficiency of spotted sea bass Lateolabrax maculatus (mean body weight 2630.8 g). The fish were tagged using four different external attachment methods with dummy biologgers: no attachment (control), anchor attachment (AA), monofilament attachment (MA), and silicon tube attachment (SA), each with triplicates. Blood indices and biologger attachment efficiency were assessed on days 1, 7, 14, 28, 56, and 84 after attachment. The concentrations of hematocrit, Na⁺, Cl^-, glutamic pyruvic transaminase and total protein, and the activity of superoxide dismutase in blood were not affected by the external attachment method of biologger. The concentrations of glutamic oxaloacetic transaminase (day 1 of attachment), hemoglobin (day 56) and total cholesterol (day 56 and 84) in AA group, the concentrations of glucose and cortisol (day 14) and total cholesterol (day 84) in MA group showed significantly higher than those of control (p<0.05). During the experiment period, the SA group had no differences from the control in all blood properties. The biologger attachment efficiencies of the AA, MA, and SA groups after 84 days were 0.0%, 33.3%, and 100.0%, respectively. These results indicate that the optimum external biologger attachment method under our experimental conditions is SA type.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.56 no.5
• /
• pp.651-659
• /
• 2023

The effect of bio-logger tagging location on blood characteristics and bio-logger attachment efficiency in spotted sea bass (mean body weight 2356.7 g) was investigated. The fish were tagged at four different tagging locations: no-tag (control), operculum attachment (OA), dorsal muscle attachment (DA), and cauda peduncle muscle attachment (CA). The blood properties and bio-logger attachment efficiencies were examined on days 1, 7, 14, and 35 after tagging the bio-logger at each tagging location. During the experimental periods, the concentrations of hematocrit and hemoglobin in whole blood, and GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transaminase), total protein (TP), glucose, total cholesterol, cortisol, and superoxide dismutase in plasma were not affected by the attachment location of the bio-logger, however, the TP concentration was significantly lower in OA than in the control group on day 7. After tagging for 35 days, the efficiencies of bio-logger attachment in the OA, DA, and CA after tagging for 35 days were 33.3%, 100.0%, and 33.3%, respectively. These results indicate that, in our experimental condition, the most appropriate bio-logger attachment location is DA, providing basic information on bio-logger utilization methods for ecological and biological biotelemetry surveys of the spotted sea bass.

• Korean Journal of Ichthyology
• /
• v.18 no.3
• /
• pp.202-208
• /
• 2006

An experiment was conducted to investigate the effects of three water temperatures (15, 20 and $25^{\circ}C$) in combination with three salinities (0, 15 and 30 psu) on the oxygen consumption rate of juvenile spotted sea bass, Lateolabrax maculatus (mean body weight $5.5{\pm}0.3g$). The oxygen consumption rates of L. maculatus were measured in triplicate for 24 hours using a continuous flow-through respirometer. Water temperature resulted in significant differences in the mean oxygen consumption rate of L. maculatus (p<0.001), but salinity and combinations of salinity and water temperature did not have (p>0.05). The oxygen consumption increased with increasing water temperatures in all experimental salinity regimes (p<001). Mean oxygen consumption rates at 15, 20 and $25^{\circ}C$ ranged 328.8~342.3, 433.9~441.0 and 651.5~659.9 mg $O_2\;kg^{-1}\;h^{-1}$, respectively. $Q_{10}$ values did not vary with salinity, bud varied with water temperature. $Q_{10}$ values ranged 1.63~1.75 between 15 and $20^{\circ}C$, 2.24~2.26 between 20 and $25^{\circ}C$, and 1.92~1.98 over the full temperature range. The energy loss by metabolic cost increased with increasing water temperatures in all experimental salinity regimes (p<0.001) Mean energy loss rates at 15, 20 and $25^{\circ}C$ ranged 224.6~233.8, 296.3~301.2 and $444.9{\sim}450.7kJ\;kg^{-1}\;d^{-1}$, respectively. These data suggest that the culture of juvenile spotted sea bass is possible without energy loss by salinity difference in freshwater as well as seawater after salinity acclimation. Thus, this result has an application for culture management and bioenergetic model for growth of this species.

• Development and Reproduction
• /
• v.4 no.2
• /
• pp.195-201
• /
• 2000

Sex differentiation process of the spotted sea bass, Lateolabrax maculatus, was investigated by histological method. The fish samples were collected from just after hatching to 365 days later. The primordial germ cells and genital ridge were appeared separately hanging under air bladder in 30-day larva (total length: 11.7~13.2 mm), and were unified into the undifferentiated gonads in 40-day larva (12.5~14.0 mm). The ovarian differentiation was started in 60-day juvenile (23.6~27.0 mm). The somatic tissues were elongated in tip of both ends of undifferentiated gonad and were fused each other. The complete ovarian cavity was appeared in 80-days juvenile(33.1~42.5 mm). The testicular differentiation was initiated in 70-day juvenile (24.8~31.6 mm). The rudiment of sperm duct was appeared in the center of the undifferentiated gonad. The meiosis of germ cells in the ovary was started in 168-day juvenile (88.0~115.4 mm). In 287-day juvenile (175.1~233.6 mm), the ovary was filled with both of chromatin stage and perinucleolus stage oocytes. The meiosis of male germ cells was started in 245-day juvenile (124.4~168.3 mm). However, the seminiferous tubules of testis were filled with numerous sperm in 365-day juvenile (162.5~253.8 mm). The sex ratio of male and female was 1:1.38. Considering these results, the spotted sea bass was showed differentiated type in sex differentiation and gonochorism in sexuality.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.6
• /
• pp.638-642
• /
• 2001

To investigate the production of $C_{21}$-steroids during the spawning period of spotted sea bass, Lateolabrax maculatus, we have incubated maturing and ovulating follicles with radiolabeled pregnenolone and $17\alpha$-hydroxyprogesterone for 24 hours. The resulting metabolites were analyzed by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC), When maturing follicles ($700\sim800{\mu}m$ in diameters) were incubated with radiolabeled precursors, $C_{21}$-metabolites were corticosteroids and $17\alpha$-hydroxy, $20\beta$-dihydroprogesterone ($17\alpha20\beta OHP$). When ovulation follicles ($1,000\sim1,150{\mu}m$ in diameters) were incubated with radiolabeled precursors, the major $C_{21}$-metabolites were $17\alpha20\beta OHP$, $17\alpha$,$20\beta$, 21-trihydroxy-4-pregnen-3-one ($17\alpha20\beta21P$), and corticosterone. Additional chromatography by TLC and HPLC confirmed the presence of radioactive $17\alpha20\beta OHP$ in the maturing follicles, and $17\alpha20\beta OHP$,$17\alpha20\beta21P$ and corticosterone in ovulating follicles. Although $17\alpha20\beta OHP$ was found in a small peak, the synthesis of this steroid suggests that it may play a role in regulating the oocyte maturation process. Whereas ovulation is regulated by both $17\alpha20\beta OHP$ and $17\alpha20\beta21P$ in the spotted sea bass. In addition, an unusual finding was the biosynthesis of corticosterone. Whether this production is responsible for the ovulation, and is an area requiring continued research.

• Journal of fish pathology
• /
• v.31 no.2
• /
• pp.115-122
• /
• 2018

The Houttuynia cordata has been utilized for various beneficial purposes in humans mainly because of its potent antioxidant principle quercitrin present in this plant. This study examines the possibility of producing a functional sea food commodity containing active principle quercitrin by feeding H. cordata for a extended period. Spotted sea bass (Lateolabrax maculatus) were fed a diet containing H. cordata at 0.1-1.0% levels for 1 month and tissue concentrations of quercitrin were analyzed in serum, hepatopancreas and muscle. It was observed that quercitrin was found in the ranking order of hepatopancreas>muscle>serum. After a bolus administration of quercitrin (20 mg/kg, oral) to spotted sea bass and Nile tilapia (Oreochromis niloticus), idential rank order was observed after 48 hr. In contrast, the order was liver>serum>muscle in rat and mice, indicating that higher quercitrin distribution occurs to the muscle in fishes compared with in mammals tested. High residue concentration of qeurcitrin in the edible tissue can be an advantageous property in terms of functional food production. High level H. cordata extract inclusion of 1.0% seems to have detrimental effects in spotted sea bass leading to growth retardation and hepatic damage. It was concluded that incorporation of H. cordata extract into diet can be a way of producing healthy foods. However the level of active extract needs fine tuning to avoid toxicity to fishes.

• Journal of Fisheries and Marine Sciences Education
• /
• v.26 no.5
• /
• pp.935-940
• /
• 2014

To investigate effect of on sexual maturation in spotted seabass, Lateolabrax maculatus the sexual maturation, photoperiods were established to natural photoperiod, 9L:15D, 11L:13D, 13L:11D and 15L:9D. After rearing for 90 days from August 11 to November 10, gonadosomatic index (GSI) and hormones were analyzed. In the female, GSI was $1.07{\pm}0.09%$ in the natural photoperiod, $1.93{\pm}0.06%$ in 9L:15D, while the GSI of male was $0.75{\pm}0.05%$ in the natural photoperiod, $1.89{\pm}0.12%$ in 9L:15D and $0.22{\pm}0.05%$ in 15L:9D and the lowest in 15L:9D, respectively. The blood estradiol (E2) of female was $226.0{\pm}13.6pg/ml$ in the natural photoperiod, and the highest value of $296.3{\pm}15.0pg/ml$ in 9L:15D. The male $17{\alpha}20{\beta}OHP$ was similar to the female with $196.3{\pm}17.0pg/ml$ in the natural photo period and $133.0{\pm}15.5pg/ml$ in 9L:15D. The testosterone (T) of male was $259.3{\pm}33.1pg/ml$ in the natural photoperiod, but the hightest value of $370.5{\pm}27.5pg/ml$ in 9L:15D. These results provide basic information from sexual maturation of spotted seabass.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.45 no.3
• /
• pp.271-282
• /
• 2012

Early osteological development of the skull, vertebral column, and fins, and squamation in the spotted sea bass, Lateolabrax maculates, were studied under extensive larval rearing conditions. The first ossification during cephalic skeleton development began with the premaxillary, dentary, and parasphenoid at 6.4 mm Total length (Notochord length 6.1 mm) and was completed by 25.2 mm TL (Standard length 20.3 mm). Ossification of the cartilaginous caudal complex started simultaneously in the urostyle and two preural centra at 12.2 mm TL (10.4 mm) and it was completely ossified by 32.0 mm TL (26.4 mm). The principal caudal fin rays, with a count of 9/8, began to ossify at 11.6 mm TL (10.2 mm) and the procurrent caudal fin rays, with counts of 4 (upper) and 3 (lower), started to ossify by 12.6 mm TL (10.9 mm). Ossification of these parts was completed by 21.4 mm TL (17.5 mm). Ossification of the vertebral column was first observed in the first to fourth centra at 8.3 mm TL (7.5 mm) and was fully completed by 21.7-35.0 mm TL (17.8-29.3 mm). The pectoral girdle started to ossify by 5.6 mm TL (5.4 mm) and was completed by 26.8 mm TL (21.8 mm). Eight pectoral fin rays were ossified at 11.6 mm TL (10.2 mm) and 16-18 rays were fully ossified by 13.8 mm TL (12.0 mm). Also, the dorsal, anal, and pelvic fin rays started to ossify at 12.2 mm TL (10.4 mm) and were completed by 12.8 mm TL (11.2 mm), 23.8 mm TL (19.4 mm), and 13.8 mm TL (12.0 mm), respectively. Ossification of the anal and dorsal pterygiophores initially occurred by 12.6 mm TL (10.9 mm) and 14.3 mm TL (12.2 mm), and was completed by 21.4 mm TL (17.5 mm) and 19.3 mm TL (15.9 mm), respectively. Squamation started at three centers of differentiation: the middle region of the trunk, the anterior of the caudal peduncle, and on the caudal peduncle at 23.8 mm TL (19.4 mm). The body was covered with scales, except the snout, at 57.2-60.2 mm TL (SL 47.1-49.2 mm).

• Journal of Aquaculture
• /
• v.20 no.1
• /
• pp.41-46
• /
• 2007

Seahorse is an interesting organism for the study of its conservation as well as development as an marine ornament fish. To investigate the ecological characteristics and fish fauna around the habitat of such an endangered species, fishes were collected from the seahorse habitat. A total of 161 fishes were classified into 8 families and 11 species including two species of seahorse, Hippocampus mohnikei and H. coronatus representing 1.9% and 1.2%, respectively, of the population. The most dominant fish species in the area was Takifugu niphobles accounting for 30.4% of the population. The predators of the seahorse such as Acanthopagrus schlegeli, Lateolabrax japonicus and Lateolabrax maculatus were found in the relative abundance of 0.6%, 5.6%, and 11.8%, respectively. The relative abundance of H. coronatus ($0.96\;ind./1,000\;m^2$), H. mohnikei ($0.97\;ind./1,000\;m^2$) and the other coexisting fishes are similar in all the areas investigated (P>0.05).