NIPPON SUISAN GAKKAISHI
Online ISSN : 1349-998X
Print ISSN : 0021-5392
ISSN-L : 0021-5392
Search
Advanced search
OR
Browse
Search
Volume 71, Issue 5
Displaying 1-16 of 16 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
Reviews
Originals
  • Melanophore development during metamorphosis in pseudo-albinic clone of Japanese flounder Paralichthys olivaceus
    AIKO NAKAMURA, TAKAHITO SHIKANO, AKIRA MIZUTA, TADAHISA SEIKAI
    2005 Volume 71 Issue 5 Pages 729-735
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.729
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      A pseudo-albinic clone and control group of normal diploid in Japanese flounder Paralichthys olivaceus were examined from the larval stage to juvenile stage through metamorphosis on the differentiation process of melanophores in relation with pseudo-albinism. On the ocular side of the control group, the larger melanophores maintained their density from the larval stage through metamorphosis, but the smaller ones rapidly increased from the climax of metamorphosis (H-stage). On the blind side, the larger melanophores maintained their density but the smaller ones did not appear through metamorphosis. In the pseudo-albinic clone, both nearly complete and partial pseudo-albinism appeared at high percentages. In completely pseudo-albinic juveniles, the distribution of melanophores on the ocular side was similar to that on the blind side in the normal group, whereas the ocular side of partial pseudo-albinic juveniles had 3 types of distribution. Therefore, it was suggested that the appearance of small melanophores played a fundamental role in normal pigmentation on the ocular side, and the failure of this process inhibited normal pigmentation.
    View full abstract
    Download PDF (400K)
  • Homing behavior of adult ocellate puffer Takifugu rubripes to the natal spawning ground at the mouth of Ise Bay based on tagging experiments
    HIROSHI NAKAJIMA, AKIRA NITTA
    2005 Volume 71 Issue 5 Pages 736-745
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.736
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      In order to clarify the homing behavior of ocellate puffer Takifugu rubripes to the natal spawning ground, adult ocellate puffers of total length 37-60 cm caught by purse seine net at the spawning ground off Anori, Mie Prefecture, were released at a location 3 miles south of the spawning ground with disk tags attached in 1996, 1997 and archival tags attached in 1998. The numbers of individuals released in 1996, 1997 and 1998 were 217, 69 and 5, and respectively 58, 14 and 3 fish were recaptured within the area of Ise Bay, Kumano Nada and Enshu Nada. Four individuals released in 1996 and one in 1998 apparently returned to the same spawning ground in the next spawning season after being released. One individual released in 1997 was recaptured very close to the spawning ground off Anori in April 1998. These results imply that adult ocellate puffer return to the same spawning ground and strongly support that this species shows homing behavior to the natal spawning ground. The fish with archival tags implanted were distributed almost within a ±2° longitudinal area around the release and recapture location. It is concluded that adult ocellate puffer seldom migrate in and out between the Kumano and Enshu Nada area and other areas.
    View full abstract
    Download PDF (1080K)
  • Effect on bivalve molluscs of a harmful dinoflagellate Heterocapsa circularisquama isolated from Omura Bay, Japan and its growth characteristics
    TOSHIFUMI YAMATOGI, MASAO SAKAGUCHI, MASAHIKO MATSUDA, SHUNSUKE IWANAG ...
    2005 Volume 71 Issue 5 Pages 746-754
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.746
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      Heterocapsa circularisquama is a red-tide forming dinoflagellate causing mass mortality of bivalve molluscs in Western Japan. Bioassay on bivalve molluscs was made using two strains of H. circularisquama isolated from Omura Bay, Nagasaki Prefecture in 1999 and 2002. Pearl oyster Pinctada fucata died within 2-3 days after being exposed to 5,000 cells/mL of H. circularisquama. Short-neck clam Ruditapes philippinarum died within 4-6 days after being exposed to 5,000 cells/mL of H. circularisquama. The growth characteristics of H. circularisquama isolated from Omura Bay in 1999 were examined in 54 different combinations of temperature (10-30°C) and salinity (16-36) under a light intensity of 80 μmol/m2/s. H. circularisquama reproduced at 12.5-30°C and 16-36 in salinity. The highest growth rate was obtained at 30°C and 32 in salinity. Under the conditions, maximum specific growth rate was 0.91 day-1. The effect of light intensity on the growth of H. circularisquama was examined at seven different conditions ranging from 10 to 140 μmol/m2/s under 14 h light and 10 h dark cycle and 25°C. H. circularisquama grew well at a light intensity of 20 μmol/m2/s and higher, then the growth was saturated at 80 μmol/m2/s. Under the conditions of this experiment, the half-saturation constant for growth of light intensity (Ks) and threshold value (Io) were 24.0 μmol/m2/s and 15.5 μmol/m2/s, respectively. The occurrence of H. circularisquama in Omura Bay, Imari Bay and Tachibana Bay was confirmed in the present study by observation of body scale structures.
    View full abstract
    Download PDF (1072K)
  • Stranded debris of foamed plastic on the coast of Eta Island and Kurahashi Island in Hiroshima Bay
    SHIGERU FUJIEDA, KAZUYA SASAKI
    2005 Volume 71 Issue 5 Pages 755-761
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.755
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      Expanded polystyrene (EPS) floats are used abundantly for the floats of oyster farming rafts in Hiroshima Bay. This paper investigated the occurrence of stranded debris of foamed plastics, stranding and unsuitable use of EPS floats on the coast of Eta and Kurahashi Islands in the Bay. Stranded debris of foamed plastic was collected from sand samples of 34 sites. Stranded floats on the beach and unsuitably used floats without covers for mooring buoys and fenders on the sea were observed visually at 58 sites along 48.6 km of coastline.
      The total number of collected debris was 245,656 items. Plastics accounted for 99.9% of the total number. Foamed plastic fragments accounted for 99.5% of the total, the size of under 10.0 mm represented 98.5% of the fragments, and the average density was 44,521.3 pieces per m2. Unsuitably used floats totaled 6,760, and the density was 140.7 pieces per harbor. The density of stranded floats was 1.1 pieces per km. The densities of unsuitably used floats, stranded floats and foamed plastic fragments on the coast of Eta Island were higher than those of Kurahashi Island.
    View full abstract
    Download PDF (693K)
  • Seasonal changes in oxygen consumption rates and filtration rates of the cultured Pacific oyster Crasssotrea gigas
    SATORU AKASHIGE, YASUSHI HIRATA, KEISUKE TAKAYAMA, KIRIE SORAMOTO
    2005 Volume 71 Issue 5 Pages 762-767
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.762
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      The oxygen consumption rates (OCR: mgO2/h/ind.) and filtration rates (FR: L/h/ind.) of the cultured Pacific oyster Crassostrea gigas in different sizes were measured in a still water system at different seawater temperature in various seasons. OCR of each oyster were measured for three to four hours in a closed chamber of 1 or 5 litters, according to the size of each animal. FR of each oyster were measured by determining the removal rates of particles of cultured diatom Chaetoceros calcitrans, which were suspended initially in filtered seawater of 30 litters at concentrations of 5-6×104 cells l-1.
      For each temperature allometric relationships (OCR or FR=aWdb) between these rates and dry-flesh weight (Wd, g) of the oyster were estimated. In case of OCR parameter b was 0.75±0.10 (mean±standard deviation), showing no relationships with seawater temperature. The value of parameter a varied according to seawater temperature(t) over the range (11.6-26.5°C), and OCR were expressed by the formula: OCR=(0.072t-0.64)Wd0.75.
      In case of FR the value of parameter b was 0.96±0.24, showing no relationship to seawater temperature. The value of parameter a varied according to seawater temperature over the range (9.7-25.7°C), and FR were expressed by the formula: FR=(0.70t-6.6)Wd in non-spawning season. In spawning season, when the value of a were constant around 4.9, which was lower value than that expected by the formula applied in non-spawning season, FR were expressed by the formula: FR=4.9Wd.
    View full abstract
    Download PDF (332K)
  • Relationships between genetic diversity and number of successive generations in hatchery populations of ayu Plecoglossus altivelis assessed by microsatellite DNA polymorphism
    MINORU IKEDA, SHUZO TAKAGI, NOBUHIKO TANIGUCHI
    2005 Volume 71 Issue 5 Pages 768-774
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.768
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      We examined the genetic variation of one wild and eight hatchery populations of ayu Plecoglossus altivelis assessed by the microsatellite DNA polymorphism. All hatchery populations had persisted for a number of generations from F4 to F31. Six out of the eight had propagated without the introduction of any other stock, however, not a few wild individuals had been mixed with each parental stock of the remaining two hatchery populations through their generations. All hatchery populations even in the mixing populations showed lower genetic variation, i.e. the mean number of alleles (A) and average heterozygosity (He), than those of the wild population. Strong significant correlations between the number of successive generations and both indices of genetic variability could be approximated by a negative linear line in He, but by a negative exponential curve in A. This result suggests that A in hatchery populations reduces faster than He during their captive propagation. The significant homozygote excess was also observed at almost all hatchery populations, indicating that inbreeding could be promoted within hatchery populations. All results would be attributed to genetic drift and/or adaptation of the captive stocks to the culture conditions.
    View full abstract
    Download PDF (297K)
  • Expanded DeLury's method with variable effectiveness of fishing effort
    NORIO YAMASHITA, MASATOSHI HASEGAWA
    2005 Volume 71 Issue 5 Pages 775-781
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.775
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      We developed an expanded DeLury's method that adjusted to the diving fishery exploiting abalones along the coast of Shirahama in Shizuoka Prefecture. In the early phase of the fishery, which started in 1982, an increase in catch per unit effort was observed with fishing season. Assuming that this was caused by a change in effectiveness in fishing effort, we applied the expanded DeLury's method allowing for such change to the catch-effort from 1982 to 1997. We assumed some mathematical models for on the change in effectiveness of fishing effort. The parameters were estimated by the maximum likelihood procedure. Several models with different constraints were compared using the Akaike information criterion (AIC). The model with the lowest AIC suggested that the effectiveness of fishing effort increased linearly during the fishing season. Modifications of the model were also discussed.
    View full abstract
    Download PDF (366K)
  • Process of true ambicoloration in larval and juvenile Japanese flounder Paralichthys olivaceus: An ultrastructural study
    YUTAKA HAGA, KEI NATAAMI, TOSHIO TAKEUCHI
    2005 Volume 71 Issue 5 Pages 782-790
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.782
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      This study investigated the process of true ambicoloration in larval Japanese flounder Paralichthys olivaceus induced by retinoic acid. Larvae at around F-G stages (TL 8.0±0.75 mm) were immersed in 50 nM all-trans retinoic acid for 5 days and reared until 60 days post hatch (dph) in order to develop true ambicoloration. Skin of fish was sampled every 4 days after immersion and subjected to ultrastructural analysis by transmission electron microscope. Melanophages started to be observed in the skin on the blind side of control fish at 30 dph. However, there were no melanophages in fish treated with atRA at 30 dph. In addition, larval type melanophores were observed under the subepidermal collagenous lamella in the skin on the blind side of fish treated with atRA. Only irridophores existed in skin on the blind side of the control fish at 40 dph. However, all three kinds of chromatophore existed on both sides of the skin of fish treated with atRA at 40 dph. These results suggested that the developmental process of pigmentation on the blind side of fish showing true ambicoloration mimicked that on the ocular side.
    View full abstract
    Download PDF (2232K)
  • Optimum management policy and evaluation of the prohibition of fishing for shirasu (anchovy larvae) fisheries using Y/R
    NAOTAKA YASUE, RYOICHI UTSUMI, AKIHISA MORIYAMA
    2005 Volume 71 Issue 5 Pages 791-796
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.791
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      We studied the optimum management policy for shirasu fisheries in the eastern waters of the Kii Channel using Y/R and evaluated the effect of the prohibition of fishing from March 26 to April 7 in 2004. Y/R is the future yield of an individual at the age of recruitment and two cases of Y/R, under non-fishing and fishing, were compared. In the actual case that fishing was opened on April 8, the effect of the prohibition of fishing was 1.60 times in comparison with the case of non-prohibition. The ideal case can be attained by opening on April 9, for which the effect is 1.61 times, which almost corresponds with the actual case. It is effective to continue this fisheries management.
    View full abstract
    Download PDF (464K)
  • Catch and distribution of young-of-the-year ocellate puffer Takifugu rubripes in Ariake Sound
    YASUHARU MATSUMURA
    2005 Volume 71 Issue 5 Pages 797-804
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.797
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      To estimate the amount of catches in number, weight and cash value of young-of-the-year (YOY) ocellate puffer Takifugu rubripes in Ariake Sound from September to December, an investigation on the basis of catch statistics at the landing markets from 1991 to 1995 and from 1999 to 2002 was conducted. Annual catches ranged from 21,000 to 88,000 in number; from 3.1 to 20.0 tons in weight and from 8 to 47 million yen in sales. The majority of the catches was brought in by angling fishery and longline fishery. Catch information obtained by a questionnaire survey of fishermen during the fishing season in 1995 showed that YOY are distributed in inshore regions of less than 10 m depth in September, at 5-20 m depth in October by migration to offshore, and inshore off Shimabara city from November to December by migration to the south. Annual change of CPUE of YOY in Ariake Sound showed a wide fluctuation from 4 to 26 kg boat•day and the same tendency as those in Yatsushiro Sea and Fukuoka Bay.
    View full abstract
    Download PDF (1497K)
  • Optimal release strategy of hatchery-produced ocellate puffer Takifugu rubripe in Ariake Sound by mark-recapture experiments, based on the stocking effectiveness for young-of-the-year
    YASUHARU MATSUMURA
    2005 Volume 71 Issue 5 Pages 805-814
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.805
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      This study evaluated the stocking effectiveness of hatchery-produced ocellate puffer by sampling surveys at fish markets in Ariake Sound where young-of-the-year (YOY) puffer are landed. The recapture rate of released seeds (3-100 mm in total length) for each annual release in the three areas Shimabara coast, Isahaya Bay, and the innermost area of Ariake Sound was estimated at between 0.01 and 22.3%, and was found to increase with increasing release size and showed a tendency that the recapture rates of seeds released at Isahaya Bay and the innermost area are higher than that at Shimabara coast. The contribution rate of the released puffer to the total landings in number was estimated to range between 6 and 52%. Stocking effectiveness was shown in Fukuoka, Saga, Kumamoto and Nagasaki prefectures and the ratios of landing number and value differed among the release sites. It was suggested that 75 mm in total length is the optimal size for release and Isahaya Bay and the innermost area in Ariake Sound are the best sites for release in terms of the ratio of landing cash value to the cost of seed.
    View full abstract
    Download PDF (552K)
  • Toxification of cultured puffer fish Takifugu rubripes by feeding on tetrodotoxin-containing diet
    SHUNICHI HONDA, OSAMU ARAKAWA, TOMOHIRO TAKATANI, KATSUYASU TACHIBANA, ...
    2005 Volume 71 Issue 5 Pages 815-820
    Published: 2005
    Released on J-STAGE: October 07, 2005
    DOIhttps://doi.org/10.2331/suisan.71.815
    JOURNAL FREE ACCESS
    Show abstractHide abstract
      A total of 5 feeding experiments were conducted, in which non-toxic cultured puffer fish ‘torafugu’ Takifugu rubripes were reared for 60 days with various types of tetrodotoxin (TTX)-containing diets. The test fish administered with a crude extract from toxic tissues of a wild puffer ‘nashifugu’ T. vermicularis accumulated a small amount of TTX (less than 3 MU/g in most cases) mainly in the skin and liver at low dose (0.1 MU/(1 g body weight•day)), and a large amount (up to 57 MU/g) mostly in the liver and ovary at higher doses (0.2-1.0 MU/(1 g body weight•day)). The accumulation rate of toxin in 0-year-old fish reared in aquaria was calculated to be 0-17%, whereas that in 1-year-old fish reared in netcages to be more than 30%. The toxin, once accumulated in the puffer tissues, was retained there for at least 45 days without any toxic diet being supplied. When a purified sample of TTX (95% purity) was administered, the puffer accumulated it up to similar levels as in the crude toxin. The fish were also found to accumulate generally high concentrations of toxin if directly fed with minced tissues of T. vermicularis.
    View full abstract
    Download PDF (283K)
Short Paper
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top