巻号一覧
63 巻, 1 号
選択された号の論文の22件中1～22を表示しています
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安 永一, 有元 貴文1997 年 63 巻 1 号 p. 3-9
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーThe stimulating effect of strobe light on jack mackerel Trachurus japonicus was examined for the heart rate change under different flash frequencies. Heart rate change was clearly observed to increase during strobe flashing, with a tendency of sudden decrease immediately after ending of the stimulus. The observation was repeated three times for each individual with an interval of two hours. The data analysis focused on the stimulating effect of the strobe light with flash frequencies ranging from 1.7 ?? 430Hz, as well as habituation by repeated trials. Under these test conditions, the flash frequencies of 5 and 10Hz produced the strongest effect of strobe stimulus. There was no significant decrease of the stimulating effect by the repeated trials, suggesting that of habituation does not occur.抄録全体を表示PDF形式でダウンロード (499K) -
藤永 克昭, 中尾 繁1997 年 63 巻 1 号 p. 10-16
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーSeasonal changes in the assimilation energy of Neptunea arthritica in Usu Bay, Hokkaido were examined. In adults, energy directed to growth was largest in summer, and energy accumulated as reproductive output was largest in autumn. The assimilation energy levels that sustained metabolism during those periods were considerably higher than during winter and spring. The assimilation energy levels in immature individuals showed less variation than in adults.
Net growth efficiency exhibited a convex curve with a peak (49.4%) at 2 years old. In both males and females, the proportion of assimilation energy utilized for reproductive output increased with age. The proportion of investment in females was 3 to 6 times that of males, owing to the production of egg capsules. The production efficiency of adults remained relatively constant at 35 to 40%, except for 5 years male, which showed 25.0%.抄録全体を表示PDF形式でダウンロード (566K) -
堀井 貴司1997 年 63 巻 1 号 p. 17-22
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーThe annual reproductive cycle and lunar spawning rhythms in the spawning season of the purple sea urchin A. crassispina, which lives in Mera Bay of South Izu in Shizuoka, were examined by the successive change of the gonad index and histological observation of the gonad. The following is the annual reproductive cycle of the purple sea urchin; the gonad become to develop from January to May, the spawning season to be from June to August, and the gonadal growing action to degenerate from September to December. Moreover, it was suggested that this cycle is closely related to the annual change of the sea water temperature. As the population of this species spawned several times every full moon period in the spawning season, they were thought to have lunar spawning rhythm that spawns once each the lunar period. It was suggested that the gonad in the spawning season could recover for the next spawning in about a week.抄録全体を表示PDF形式でダウンロード (406K) -
松下 吉樹, 井上 喜洋1997 年 63 巻 1 号 p. 23-29
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーSquare mesh codend selectivity experiments for walleye pollock Theragra chalcogramma were carried out along the Pacific coast of the Kuril Islands and off Miyagi, Tohoku. Selection curves varied by differences in body shape. Catches taken off Miyagi tended to retain smaller individuals when compared with catches using the same codend mesh size off the Kuril Islands. A detailed investigation of the total length-body girth relationship showed that there were significant differences in the maximum body girth of walleye pollock for fish of the same length. It was also observed that when the catch of fish in the selection range was relatively small, the selection curve tended to be sharp. The selection master curve was expressed in terms of the retention ratio of the codend to the body girth (G) and mesh perimeter (P) ratio (G/P). From these findings, it is suggested that selectivity research should include investigations of changes in the target body shape in the fishing grounds.抄録全体を表示PDF形式でダウンロード (505K) -
山崎 淳1997 年 63 巻 1 号 p. 30-34
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーThe present paper investigates the carapace width compositions of soft-shell males Chionoecetes opilio caught by Danish seiners and the effectiveness of prohibition of catching soft-shell males in order to keep the optimum sex ratio at 0.47 (ratio of the number of terminal molt males with hard-shell to the number of multiparous females). The sex ratio was estimated to be 0.37 in the present fishing intensity for multiparous females, hard-shell and soft-shell males in the Sea of Japan.
Soft-shell males were mainly less than 100mm carapace width and non-terminal molt regardless of carapace size, and terminal or non-terminal molt cannot mate with multiparous females. It seems that the abundance of recruitment to functional maturity males with hard-shell decreases due to the catch of soft-shell males.
It was ascertained that the optium sex ratio would be maintained at the present fishing condition for hard-shell males with fishing coefficient 0.5 year-1 decreased effort for multiparous females and prohibition of soft-shell males catch.抄録全体を表示PDF形式でダウンロード (429K) -
梁 振林, 松田 皎, 東海 正1997 年 63 巻 1 号 p. 35-42
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーThis paper proposes a model of fish behavior toward a leader net set on the sea bottom with a gradient on the assumption that the force of the directional field makes the fish swim in the direction of deeper water within a range around the leader net. In a box-net with a bottom gradient in an octagonal water tank, the swimming behavior of rainbow trout Oncorhynchus mykiss toward the leader net was recorded with a video recorder. Bottom gradients used in the experiment were 2.5, 5.0 and 7.5 degrees. Paramenters of this model were estimated from time-series data of the position of fish using the least-squares algorithm. Observations of fish swimming in the water tank show that fish tend to swim in the deeper part of the box-net. The swimming trajectory of fish in the model simulation demonstrates the same tendency as the actual observations. Furthermore, the steeper the bottom, the larger the parameter value of the force of the directional field, demonstrating the validity of this model.抄録全体を表示PDF形式でダウンロード (508K) -
浜田 弘之1997 年 63 巻 1 号 p. 43-49
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーThis paper describes the number of fish and crab caught and discarded in individual bag-nets set at different positions in a small set-net. Most of the fish tended to be caught in the bag-nets at one or both ends in four fish species: S. Zunasi, K. punctatus, C. affinis and L. japonicus, whilst the two crabs C. japonica and P. trituberculatus were caught mainly in the bag-nets around the central part of the fence net. The differences between bag-nets in number of each species caught are discussed in terms of gear design and in particular the design of the fence net and the swimming behavior of these spe-cies. The Mesh size of bag-nets in the small set-net fishery in the Buzen Sea is small to catch small-size shrimp. This leads to by-catch of juveniles of the target fish, in particular L. japonicus, one of the most important species. Assuming that small shrimp are likely to be caught in the bag-nets around the central part of the fence net as previously described in some papers, the result of this paper sug-gests the possibility that larger mesh size in both end bag-nets may allow juvenile L. japonicus to escape through the mesh of these bag-nets without reducing the catch of small shrimps.抄録全体を表示PDF形式でダウンロード (537K) -
井口 謙, 中谷 敏邦, 高津 哲也, 高橋 豊美1997 年 63 巻 1 号 p. 50-55
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーRainbow smelt Osmerus eperlanus mordax, were collected during May 1993 to April 1995 from Funka Bay, Hokkaido, and the Yamazaki and Rukotsu rivers, which flow into the western side of the bay. Ovarian eggs from females were examined histologically. Oocytes from the chromatin-nucleolus stage to the ripe stage were found in the ovaries. From May to August, females had immature oo-cytes in the yolkless stage and yolk vesicle stage. Postovulatory follicles were also found in the ovaries of females collected from the bay in May. After November, a bimodal distribution of egg diameter was observed. More advanced oocytes developed from the primary-yolk stage in November to the migratory-nucleus stage in April. These observations indicate that group-synchronous oocyte development occurred.
All oocytes in the migratory-nucleus stage from females collected by set nets in the coastal area off Mori were found in late April. From late April to mid-May, oocytes of females collected from the two rivers were in the ripe stage. These results suggest that rainbow smelt inhabiting Funka Bay spawn from late April to mid-May in the rivers flowing into the western coast of the bay. Visual observations of adults in the rivers and the developmental process of oocytes indicate that rainbow smelt return to the sea after spawning.抄録全体を表示PDF形式でダウンロード (1315K) -
安信 秀樹, 永山 博敏, 中村 和代, 畑井 喜司雄1997 年 63 巻 1 号 p. 56-63
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーHalocrusticida (=Atkinsiella) okinawaensis was isolated from diseased swimming crab larvae Portunus trituberculatus in the Hyogo Prefectural Mariculture Center, and pathogenicity of the isolates was confirmed by infection experiments with zoeal larvae of the crab. The isolates grew in PYGS broth at pH 5-9, but the growth at pH 9.25 was remarkably reduced.
Experimental infections using zoea-I demonstrated that the infection with H. okinawaensis was controlled by keeping the pH of reaing water at 9.25. Acute toxicities of pH 9.25 to swimming crab zoea, rotifer Brachionus plicatilis rotundiformis, brine shrimp Artemia salina, and unicellular alga Nannochloropsis sp. were not observed. Survival rates of swimming crab larvae from zoea-I to juvenile crab-I in the center were apparently raised by applying this pH adjustment at 9.25.抄録全体を表示PDF形式でダウンロード (596K) -
土田 修二, 田端 重夫1997 年 63 巻 1 号 p. 64-69
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーTemperature preference of 2-14 month old striped beakperch, Oplegnathus fasciatus, (B. L. 3.3-14.9cm) hatched on the same day was tested using a vertical temperature gradient tank. Fish were acclimated to 25°C for more than 18 days before the experiments. Temperature was a dominant factor affecting fish distribution in a vertical temperature gradient, since the distribution was shifted in accordance with the location of preferred temperature. No clear change in the preferred temperature was shown with exposure to the temperature gradient for more than 24 hours. The preferred temperatures were related to the growth of the fish. Two to eight month old fish preferred a progressively cooler temperature from 28.6 to 24.7°C as they grew. Fish older than 8 months preferred a narrower temperature range of 25 and 26°C.抄録全体を表示PDF形式でダウンロード (436K) -
示野 貞夫, Toni Ruchimat, 松本 将哉, 宇川 正治1997 年 63 巻 1 号 p. 70-76
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーFingerling yellowtail Seriola quinqueradiata were fed fish meal-based moist pellet diets containing 0-30% commercial full-fat soybean meal (FFSB) in 0.8 ton aquaria for 30 days. Higher inclusions of FFSB slightly decreased protein and carbohydrate digestibilities and hemoglobin concentration. However, fish fed diets containing less than 30% FFSB resulted in a comparable growth rate, feed utilization efficiency, and body composition to those of fish fed a FFSB-free control diet. Extruding the FFSB-containing diet markedly improved growth performance and hematological characteristics in despite of unaltered amino acid composition, trypsin inhibitor activity, and antigen content in the diet. No improvement was observed when only FFSB in the diet was extruded or heated. These results suggest that FFSB is a potential alternative protein source, and extrusion of diet improves its nutritive value.抄録全体を表示PDF形式でダウンロード (498K) -
鄭 鋒, 竹内 俊郎, 小林 真人, 廣川 潤, 渡邉 武1997 年 63 巻 1 号 p. 77-84
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーAn experiment was conducted to determine the absorption of vitamin E (VE, α-toc.) in rotifer and cod larvae, and the effect of DHA content in rotifer on the dropsy rate of cod larvae. In this experiment, rotifers were enriched with dry shark eggs supplemented with different levels of three types VE, such as DL-α-toc. acetate, DL-α-toc. free, or D-α-toc. free.
It was shown that D-α-toc. free was accumulated in rotifer more efficiently than DL-α-toc. free. Cod larvae can convert DL-α-toc. acetate to a free type of VE, but its absorption was low compared with the free type of VE. Furthermore, it was also found that the occurrence of dropsy rate in cod larvae reduced when the DHA content in rotifer was increased.抄録全体を表示PDF形式でダウンロード (612K) -
黒島 良介, 角埜 彰, 小山 次朗1997 年 63 巻 1 号 p. 85-89
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーOrganotin compounds have been used as anti-fouling reagents having high toxicity to aquatic organisms. In this study, in order to assess the toxic effects of triphenyltin on fish, potential activities of chymotrypsinogen and trypsinogen in the liver of red sea bream, Pagrus major, and the activities of chymotrypsin and trypsin in the intestine were determined. The red sea bream were exposed to triphenyltin ranging from 0.13μg/l to 3.23μg/l for up to 8 weeks. The potential activities of chymotrypsinogen and trypsinogen in the liver of exposed fish were much lower than those in the control fish, whereas the active forms of these enzymes in the intestine were not affected by the exposure to triphenyltin. The feeding activity of fish exposed to tiphenyltin of 3.23μg/l was depressed. The results of the relationship between diet amounts given and enzyme activities suggested that starvation caused a remarkable decrease in the potential activities of the zymogens in the liver, suggesting the depression of potential activities of the zymogens in the liver of exposed fish was not caused by the change in feeding activity of fish but by the toxic effects of triphenyltin. The potential activities of the zymogens were influenced by the exposure to triphenyltin of 0.13μg/l for 4 weeks.抄録全体を表示PDF形式でダウンロード (394K) -
任 恵峰, 林 哲仁, 大久保 忠利, 後藤 純雄, 遠藤 英明, 渡辺 悦生1997 年 63 巻 1 号 p. 90-96
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーFor the Ames test, mutagenic compounds must be separated from free histidine before quantitative determination of the mutagenicity of foods. This separation process may cause mutagenic compounds having similar chemical characteristics with histidine to be only partially recovered from the sample. We studied the recovery ratio of several mutagens before and after separation by forward mutation assay and the Ames test. In this report we reveal 1) the difficulty of quantitative analysis on the measurement of total mutagenicity by the Ames test, 2) the negligible influence of the presence of free histidine on the determination by the forward mutation test, and 3) better detecting sensitivity of Salmonella typhimurium TM677 on the sample at the same concentration.抄録全体を表示PDF形式でダウンロード (730K) -
伊藤 慎悟, 吉水 守, 絵面 良男1997 年 63 巻 1 号 p. 97-102
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーThe disinfectant effects of total residual oxidants (TROs) produced by ozonization of artificial seawater on fish pathogenic bacteria and viruses were investigated. A dose of0.1mg TROs/l was not stable in natural seawate, but was stable in artificial seawater with a bromine compound (sodium bromide). By the treatment with TROs of 0.1mg/l for 30 to 120 seconds, more than 99.9% of viable cells of Vibrio anguillarum, Aeromonas salmonicida, A. caviae, A. hydrophila, and Escherichia coli were killed, and 99.9% of infectivity of hirame rhabdovirus (HIRRV), infectious hematopoietic necrosis virus (IHNV), infectious pancreatic necrosis virus (IPNV), and yellowtail ascites virus (YAV) were inactivated. HIRRV was more than 99.7% inactivated by a treatment with a dose of 3.5g/m3 of ozone gas bubbles for 1 min.抄録全体を表示PDF形式でダウンロード (444K) -
野村 明, 伊藤 慶明, 山本 友紀, 小畠 渥1997 年 63 巻 1 号 p. 103-104
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (1714K) -
添田 秀男, 川村 軍蔵, 畠山 良己, 竹村 暘, 梨本 勝昭1997 年 63 巻 1 号 p. 105
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (51K) -
畠山 良己1997 年 63 巻 1 号 p. 106-107
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (156K) -
山川 正已1997 年 63 巻 1 号 p. 108-109
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (155K) -
本松 敬一郎1997 年 63 巻 1 号 p. 110-111
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (146K) -
小島 隆人1997 年 63 巻 1 号 p. 112-113
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (173K) -
安樂 和彦1997 年 63 巻 1 号 p. 114-115
発行日: 1997/01/15
公開日: 2008/02/29
ジャーナル フリーPDF形式でダウンロード (172K)
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