Limanda Yokohamae Research Articles

광양만 대도 주변에 서식하는 어류군집의 변화

광양만 대도주변에 서식하는 어류군집의 변화를 파악하기 위해서 2009년 3월부터 2010년 2월까지 소형 빔트롤을 이용하였으며, 동일 해역에서 실시된 이전 연구결과(1990~1991, 1995~1996)와 비교, 고찰하였다. 조사기간 동안 총 74종, 8,133개체가 출현하였다. 우점종은 주둥치, 보구치, 점줄망둑, 청보리멸, 열동가리돔, 풀반지, 돛양태, 베도라치, 도다리, 쥐노래미, 문치가자미 순으로 나타났다. 이들 11어종은 전체 개체수의 89.5%, 총 생체량의 58.9%를 차지하였다. 우점종이었던 개체들은 주로 작은 크기의 어종과 대형 어류의 치어였다. 종조성 및 출현량은 계절에 따라서 크게 변하였다. 2009년 5월과 10월에 가장 많은 종수가 출현하였으며, 2009년 5월에 개체수와 생체량이 가장 높았다. 출현 개체수 및 생체량은 모두 2010년 1월과 2월에 가장 낮았다. 어류군집의 계절변동은 수온변화와 연관이 있었다. 이전 연구결과와 비교하였을 때, 단위면적당 전체 개체수와 생체량은 더 높았으며, 주둥치의 출현량은 급격히 증가한 반면에 꼼치의 출현량은 감소하는 양상이었다. 어류군집의 종조성 변화는 광양만내의 전반적인 해양환경 특성의 연간변화에 기인하였다. Changes of fish assemblage inhabiting around Dae Island in Gwangyang Bay, Korea were investigated using a small beam trawl monthly from March 2009 to February 2010. These data were compared with those obtained in previous studies(1990~1991 and 1995~1996) at our study sites. A total of 8,133 fish belonging to 74 species in 38 families were collected. Leiognathus nuchalis, Argyrosomus argentatus, Acentrogobius pellidebilis, Sillago japonica, Apogon lineatus, Thryssa hamiltoni, Repomucenus richardsonii, Pholis nebulosa, Pleuronichthys cornutus, Hexagrammos otakii, and Limanda yokohamae dominated, and these were responsible for 89.5% and 58.9% in the number of individuals and in biomass, respectively. These were primarily small species or early juveniles of larger species. Seasonal variation in both species composition and abundance was large: the peak number of fish species occurred in May and October 2009, whilst both number of individuals and biomass were the highest in May 2009. Fish numbers as well as biomass was lowest in January and February 2010. Seasonal changes in the abundance of fishes corresponded with temperature. Compared with the previous studies, the total number of individuals and biomass per unit area(<TEX>$m^2$</TEX>) were higher, and the predominance of L. nuchalis occurred while abundances of Liparis tanakai were significant decreased. These results seemed to be change of species composition in fish assemblage which was due to variation of annual environmental characteristics in Gwangyang Bay.

Effect of population density and tank color on the abnormal coloration of hatchery-reared mud dab, Limanda yokohamae

Effect of population density and tank color on the abnormal coloration of hatchery-reared mud dab, Limanda yokohamae

Age and Growth of Marbled Sole, Limanda yokohamae in the Northern Part of Kii Channel

Age and Growth of Marbled Sole, Limanda yokohamae in the Northern Part of Kii Channel

Growth and behavior of larvae of the Marbled Sole Limanda yokohamae (GÜNTER) in low water temperature

Growth and behavior of larvae of the Marbled Sole Limanda yokohamae (GÜNTER) in low water temperature

Growth and Metamorphosis of the Marbled Sole Larvae Limanda Yokohamae (GÜNTER) in Culture

Growth and Metamorphosis of the Marbled Sole Larvae Limanda Yokohamae (GÜNTER) in Culture

Characterization of cholinesterases in marbled sole, Limanda yokohamae, and their inhibition in vitro by the fungicide iprobenfos

Cholinesterases (ChEs) have been characterized in marbled sole (Limanda yokohamae) for use as a possible biomarker of pollution exposure. In brain, ChEs existed almost exclusively (>95%) as acetylcholinesterase (AChE) whereas in muscle, about 20-30% of ChE activity was in the form of butyrylcholinesterase (BChE; pseudocholinesterase). Acetylthiocholine and butyrylthiocholine (identified in mammalian studies as diagnostic substrates for AChE and BChE respectively) were hydrolyzed mainly, but not exclusively, by these enzymes. The inhibitors BW284C51 and iso-OMPA (identified in mammalian studies as diagnostic inhibitors of AChE and BChE respectively) were not specific for these enzymes in marbled sole. Brain AChE and muscle AChE and BChE were characterized in terms of their kinetic properties (KM etc.) and optimal conditions (substrate concentration, protein concentration, pH etc.) were established to allow routine assays of ChE activity to proceed under pseudo-first order conditions. The sensitivity of ChEs to a locally significant pesticide, iprobenfos (IBP; kitazin) was established in terms of IC50 concentrations. Brain AChE was relatively insensitive to IBP, but muscle AChE and BChE were sensitive to IBP concentrations in the high nM range. However, ambient IBP concentrations in Korean coastal waters are usually not high enough to cause detectable ChE inhibition in this species.

자연산 문치가자미 (Limanda yokohamae)의 난소 발달에 따른 혈중 성호르몬과 난황단백전구체 농도 변동

This study correlated changes in estradiol-l7<TEX>$\beta$</TEX> (<TEX>$E_2$</TEX>), testosterone (T), 17<TEX>$\alpha$</TEX>,20-dihydroxy-4-pregnen-3-one (DHP), and vitellogenin (VTG) levels with changes in the gonadosomatic index (GSI) and ovarian histology during the annual reproductive cycle of the wild marbled sole, Limanda yokohamae. Synchronous oocyte development occurs in this fish. Ovary maturity was classified into four periods, based on histological observations: the spawning (December to February), post-spawning (February to April), recovery (May to August), and vitellogenic (September to November) periods. Seasonal changes in the GSI were inversely correlated with water temperatures and reflected the degree of ovarian maturity. Plasma VTG levels were correlated with changes in the GSI, which increased from September to a peak in January, and levels remained comparatively high until February. Estradiol-17<TEX>$\beta$</TEX> was at baseline levels (<0.11 ng/mL) during the spring and summer, and peaked rapidly (1.55<TEX>$\pm$</TEX>0.445 ng/mL) from October to January. Plasma T and DHP levels had a similar profile; they rose markedly during the spawning period and remained low (or were not detectable) from spring through autumn. These data indicate that changes in plsama steroid hormones and VTG levels are correlated with the annual ovarian activity of the marbled sole. Based on these results and published reports, it appears that in this species DHP is the most important maturation-inducing steroid and that T is also related to final maturation.

Universal Rice Primer (URP)-RAPD 방법에 의한 어류 종 특이 marker의 동정

Morphologically similar fish species were subjected to the random amplified polymorphic DNA (RAPD) analysis using universal rice primer (URP). The fish species tested were sea basses (Lateolabrax japonicus and L. maculatus), eels (Anguilla japonica, A. bicolor bicolor, A. rostrata, and A. anguilla), and flounders (Limanda yokohamae and L. herzensteinin). Highly reproducible RAPD patterns were observed with several potential species-specific markers. The results indicate that RAPD technique using URP is useful for distinguishing fish psecies in a rapid manner.

Mercury concentration of fish in Tokyo Bay and the surrounding sea area

Total mercury in the muscles of three fish species was analyzed in fish caught in Tokyo Bay and the surrounding sea areas, Sagami Bay and Choshi. Tokyo Bay is a semi-closed sea area surrounded by Tokyo, Kanagawa and Chiba prefectures. Sagami Bay and Choshi are open to the Pacific Ocean. A total of 412 fish consisting of northern whiting (Sillago japonica), flatfish (Limanda yokohamae) and sardine (Sardinops melanosticta) were caught in these areas over a 6 months period from November 1998 to April 1999. Total mercury concentration ranged from 0.008-0.092 microgram/g (wet wt.) in northern whiting, 0.006-0.065 microgram/g in flatfish and 0.001-0.045 microgram/g in sardine. All concentrations were below the restriction limit of fish mercury in Japan, 0.4 microgram/g of total mercury concentration. A significant correlation was found between mercury concentrations and body length or body weight in northern whiting and flatfish, irrespective of the sea area. A correlation was also found between mercury concentration in fish and their feeding habits: among the 3 species caught in the same area, crustacean feeding northern whiting had the highest, polychaete feeding flatfish moderate, and plankton feeding sardine had the lowest mercury concentration. In a comparison of mercury concentration in the same species caught in different sea areas, a higher concentration was noted in fish caught in the semi-closed sea area of Tokyo Bay, than in fish caught in the open sea areas of Sagami Bay and Choshi. This difference was most marked in fish caught at the bottom of Tokyo Bay and we considered that the mercury concentration of seawater and sediment in these areas was the cause of mercury accumulation in fish. These findings suggest that improved water quality control and environmental monitoring is necessary in semi-closed sea areas such as Tokyo Bay.

Infectivity of aquabirnavirus strains to various marine fish species.

To determine the infectivity of marine birnavirus (MABV) in various marine fish species, experimental infection was performed in combination groups of 5 fish species with 7 strains of MABV and 1 strain of infectious pancreatic necrosis virus (IPNV). Mortality was observed in yellowtail Seriola quinqueradiata and amberjack S. dumerili infected with MABV strains Y-6, Y-10K and H-1, but not in other infected species. MABV was reisolated from most combination groups, but the virus isolation rate and virus infectivity titer were often significantly different among groups with the same fish species or with the same virus strain. All MABV strains replicated well in makogarei Limanda yokohamae, but only slightly in tiger puffer Takifugu rubiipes. IPNV also replicated in all fish species without causing death. The isolation rate and infectivity titer of IPNV were similar to or higher than those of non-virulent strains of MABV. In conclusion, the infectivity of MABV for different fish species is considered to change, which is an important factor in the development of the infection cycle of this virus among marine organisms.

Effects of temperature on sex determination in marbled sole Limanda yokohamae

Effects of temperature on sex determination in marbled sole Limanda yokohamae

Analyses of physiological factors inducing oocyte maturation and ovulation in a marine plaice Limanda yokohamae

Analyses of physiological factors inducing oocyte maturation and ovulation in a marine plaice Limanda yokohamae

Comparison of Gangliosides in Brain and Liver of Two Fish Species, Plecoglossus altivelis and Limanda yokohamae

For Plecoglossus altivelis and Limanda yokohamae grown in different ecological environments, ganglioside characteristics in the brain and liver were examined and compared by TLC.As with sardine reported previously, polysialogangliosides having three or more sialic acid molecules bonded to each other were found present in the brain at high concentrations, while monosialoganglioside concentration in the liver was high.These findings confirm organ-specificity. In Limanda yokohamae liver, GM2 was the main component present at 79.5%, GM4 and GD1a were detected, respectively, at 24.4% and 22.3% in Plecoglossus altivelis liver. These data differ from those for sardine whose GM4 content was 47.4%, suggesting remarkable differences among fish species. GM3 is the major component in higher vertebrate livers, and thus species-specificity may be considered reflected by ganglioside distribution in the liver.

Accumulation of tributyltin (TBT) in the blood of flounder and dab intraperitoneally administered with TBT

The present study was carried out to investigate the accumulation of TBT in the blood of cultured Japanese flounder, Paralichthys olivaceus, and dab, Limanda yokohamae. TBT-CI was intraperitoneally administered to fish at a dose of 2.5mg kg −1 b.w. At 2, 4, 6 and 8 days after the injection, the blood, liver, kidney, spleen and dorsal muscle were collected. The amounts of TBT within the tissues were determined by GC-FPD. High TBT concentrations were found in the serum of Japanese flounder, levels which corresponded to 22~37-fold those found in the muscle, and 7~12-fold those found in the liver. High TBT concentrations were also found in the serum of dab. The results of gel filtration of the serum showed that TBT was bound to an unknown substance (mol. wt ca 50000).

Effects of docosahexaenoic acid and phospholipids on stress tolerance of fish

The effects of dietary docosahexaenoic acid (DHA, 22:6( n − 3)) and phospholipids (soybean lecithin) on the stress tolerance of marine fish, i.e., larval red sea bream ( Pagrus major) and juvenile marbled sole ( Limanda yokohamae), were investigated using 20–30 days feeding trials. The tolerance of these two marine fish to various stress factors such as changes in water temperature and salinity, and exposure to low dissolved oxygen and to air were determined. Dietary DHA and soybean lecithin were effective in increasing the tolerance of red sea bream and marbled sole to the various stress conditions.

Content of phylloquinone and menaquinone derivatives in the organs of pelagic and demersal fishes

The contents of phylloquinone (PK) and menaquinone (MK)-4, 6, 7, 8 and 9 in the different organs of four species of fishes were compared. Mackerel, Scomber japonicus (Houttuyn), a typical pelagic fish, contained a large amount of PK but only trace amounts of MK-4 and MK-6 in the liver and kidney. Saury, Cololabis saira (Brevoort) contained a large amount of MK-4 in the heart and gonad, and a little PK. Marbled sole, Limanda yokohamae (Günther) and sillago, Sillago japonica (Temminck and Schlegel), demersal fish, contained relatively large amounts of MK-4 and PK but only small amounts of MK-6, 7 and 8. In marbled sole and sillago, the contents of the gastrointestinal tracts were rich in MK-long chains. While, the tissues and contents of digestive tracts of mackerel and saury contained little MK-long chains. These findings suggest that vitamin K in the tissues of fish originates from the food taken in. However, a certain discrepancy between the composition pattern of vitamin K (V. K) in the tissue and contents of the gastrointestinal tract might indicate that different forms of V. K are absorbed and/or accumulated in the tissues in a different manner.

Measurement of background‐visual field in flatfishes by CRT display method

Background‐visual fields of two flatfish species, one of which has both eyes on its embryonic left side (Paralichthys olivaceus) and the other on its right side (Limanda yokohamae), were measured by a cathode‐ray tube (CRT) display method. A CRT display was set with its screen facing upwards and a cursor was generated on it using a computer. A fish in a transparent chamber was put on the display and its eye movements while following the moving cursor was recorded as an index of visual attention. It was revealed that there is a blind area close to left eye in Paralichthys, while in Limanda the blind area is located close to the right eye. These observations confirmed the previous report that the left eye of Paralichthys does not see the immediate background. The results indicate that the information from the migrated eye might be more correct and important to flatfish for camouflage.

Evaluating method of the marine environmental capacity for coastal fisheries and its application to Osaka Bay

The methodology for the estimation of “the marine environmental capacity for coastal fisheries (E.C.)” is proposed. The characteristics of the methodology are as follows: 1) selecting and analyzing environmental factors affecting the growth and survival of fishery organisms at various developmental stages; 2) modeling the correlation of fishery organisms with their environmental factors on the basis of accumulated knowledge and experience; 3) estimating the fluctuation of fish population related to environmental conditions. For the above estimation, the environmental limits sustainable for the fisheries resources are determined by using models for the life cycle of fishery organisms. This methodology is applied to Osaka Bay. In this bay two factors are suggested to be essential to E.C. of marbled sole, Limanda yokohamae, which is representative of demersal fishes. One is the reclamation from the sea which makes narrower spawning and nursery grounds, and the other is the increased pollution load which results in a deficiency of dissolved oxygen in the bottom layer and reduces the biomass of benthonic organisms as food. The practical use of E.C. method as a tool for the environmental assessment is also discussed.

Morphological and functional development of larval and juvenile Limanda yokohamae (Pisces: Pleuronectidae) reared in the laboratory

Morphological and behavioural aspects in larval development need to be studied in detail to understand the early life history better, and to gain a comprehensive knowledge on early life stages for fish species important in aquaculture and fisheries. In the present study, larvae of Limanda yokohamae (Gunther) were reared to observe their behavioural development, and to obtain specimens for studying the morphological features and the intestinal development at Ohno, Hiroshima, Japan, in 1987. Swimming activity was monitored at several larval stages, and swimming speed was recorded until settlement and after-feeding behaviour was initiated. A slight increment of swimming speed was observed with larval growth. Larvae changed their swimming behaviour from surface waters to the bottom of the rearing tank when their eyes began to move. Morphological development of pigmentation patterns, fin development, squamation and the development of the digestive tract were described and illustrated in detail to characterize development stages, especially those relating to metamorphosis. During metamorphosis, growth ceased and rapid changes in allometric growth were accompanied by differentiation of the digestive tract. After metamorphosis there was steady growth, allometric growth achieved a constant value, and both the scales and digestive organs were fully formed. Metamorphosis was therefore a crucial developmental milestone, including a critical phase during which survival potential was lowered.

Age and growth of the pleuronectid flounder Limanda yokohamae in Tokyo Bay, Japan.

Age and growth of the pleuronectid flounder Limanda yokohamae in Tokyo Bay, Japan.