詳細

家戸　敬太郎 （カト　ケイタロウ）

  • 水産研究所　教授/白浜実験場長/富山実験場長
Last Updated :2024/04/25

コミュニケーション情報 byコメンテータガイド

  • コメント

    海水魚の養殖および種苗生産に関係するいろいろな実用的な研究を、遺伝子解析などの手法を用いて行っています。

  • 報道関連出演・掲載一覧

    ＜報道関連出演・掲載一覧＞ ●2023/5/26 　原子力産業新聞 　ALPS処理水添加の水槽での海洋生物の育成状況について ●2022/9/9 　NHK Eテレ「ギョギョッとサカナ★スター」 　「マダイ」に関するコーナーの監修 ●2021/9/4 　富山テレビ「フルサタ！」 　近大サクラマスについて ●2021/6/24 　読売テレビ「かんさい情報ネットten.」 　「泉南アナゴ」の復活に関して、その元となった稚魚の養殖技術及び完全養殖の進捗状況・展望について ●2020/11/11 　NHK富山「ニュース富山人」 　入善漁協との協力で大型なサクラマスの養殖に成功したことについて ●2020/9/18 　北日本放送「ワンエフ」 　酒粕を活用したエサをアナゴに与えることで期待されることなどについて ●2020/2/18 　和歌山放送「ラジオでお届け！県政最前線」 　和歌山県主催のシンポジウムでの講演した様子 ●2020/2/16 　テレビ和歌山「きのくに21」 　和歌山県主催のシンポジウムでの講演した様子 ●2020/2/13 　テレビ和歌山「6時のわかやま」 　ゲノム編集マダイの育成技術と市販の目標について ●2019/10/1 　読売新聞 　ゲノム編集 マダイの価格について ●2019/9/14 　読売テレビ「ウェークアップ！ぷらす」 　ゲノム編集食品を利用した養殖の将来について ●2019/9/6 　東海テレビ「ニュースOne」 　ゲノム編集技術について ●2019/7/17 　朝日新聞 　「高級魚 遺伝子操作から世話まで」について ●2019/5/9 　ＮＨＫ京都「ニュース630　京いちにち」 　ゲノム技術の可能性や課題について ●2019/4/9 　テレビ東京「ワールドビジネスサテライト」 　ゲノム編集について現在の技術や効果、課題について ●2019/3/23 　TBS「報道特集」 　ゲノム編集について ●2019/3/21 　関西ﾃﾚﾋﾞ「報道ﾗﾝﾅｰ」 　ゲノム編集について ●2019/3/18 　NHK「ニュースウオッチ9」 　肉厚マダイについて ●2019/2/1 　日本テレビ「news every」 　肉厚マダイ、サツキマスの養殖について ●2018/12/11 　富山テレビ「BBTチャンネル8」 　アナゴの研究について ●2018/12/7 　テレビ朝日「キャスト」 　肉厚マダイについて ●2018/11/14 　TBS「あさチャン！」 　肉厚マダイについて ●2018/8/20 　ＮＨＫ総合 「ＮＥＷＳ ７」 「ＮＥＷＳ　ＷＡＴＣＨ ９」 「ニュースチェック １１」 　肉厚マダイについて ●2018/8/17 　毎日放送「VOICE」 　肉厚マダイについて ●2018/4/28 　朝日放送「勝手に表彰！関西うまいもんアワード」 　各地域のマダイと近大マダイを食べ比べる ●2018/4/24 　NHK総合「ニュース シブ5時」 　肉厚マダイについて ●2018/01/05 　朝日新聞 　ゲノム編集で養殖「肉厚マダイ」について ●2018/01/05 　読売新聞 　瀬戸内アナゴの大不漁について ●2017/11/3 　産経新聞 　「堺もん」のアナゴについて ●2017/9/27 　日本経済新聞 　アナゴの完全養殖について ●2017/7/4 　日本経済新聞 　アナゴの水揚げの減少について ●2017/5/2 　産経新聞 　ご当地サーモン加速「国産で安心」養殖ブームについて ●2016/10/27 　朝日新聞 　魚の品種改良について ●2016/2/14 　朝日新聞 　マダイについて ●2015/07/29 　NHK総合「ニュースほっと関西」 　大きなマダイを育てる「ゲノム編集」技術について ●2015/07/29 　NHK総合「ニュース7」 　大きなマダイを育てる「ゲノム編集」技術について

研究者情報

学位

  • 農学博士（近畿大学）

ホームページURL

J-Global ID

研究キーワード

  • 水産増殖学   Science of Aquaculture   

現在の研究分野（キーワード）

    海水魚の養殖および種苗生産に関係するいろいろな実用的な研究を、遺伝子解析などの手法を用いて行っています。

研究分野

  • ライフサイエンス / 水圏生産科学

所属学協会

  • 日本生物工学会   日本分子生物学会   日本水産増殖学会   日本水産学会   

研究活動情報

論文

  • Ryuichiro Aoki; Shukei Masuma; Youhei Washio; Hisashi Chuda; Keitaro Kato
    Fisheries Science 2024年04月
  • Haruhisa Fukada; Hiroshi Yabuki; Chiemi Miura; Takeshi Miura; Keitaro Kato
    Fisheries Science 89 2 191 - 202 2023年03月 
    To improve the production efficiency of yellowtail Seriola quinqueradiata aquaculture, we measured changes in the activities of two lipid metabolism-related enzymes, carnitine palmitoyltransferase 2 (CPT2) and glucose-6-phosphate dehydrogenase (G6PDH), in the dark muscle and livers of 0- and 1 year-old fish over the entire culture period. Concomitantly we also investigated two factors that regulate these enzymes, namely, water temperature and daylength, under natural and controlled light conditions. In 0 year-old fish, high CPT2 activity was observed with increased water temperature/longer daylength, whereas high G6PDH activity was observed with decreased water temperature/shorter daylength. The activities of these enzymes were inversely correlated with each other. The changes in CPT2 and G6PDH activities were similar in 1- and 0 year old fish cultured with and without light control. To determine the major regulatory factors of CPT2 and G6PDH activities, two experiments were performed, starting on the vernal and autumnal equinox days, respectively. Fish were reared under natural and controlled light conditions (light:dark, 12:12 h) in both experiments. CPT2 activity did not differ according to light conditions or water temperature. G6PDH activity did not differ according to light conditions, but an increase in G6PDH activity was confirmed upon lowering of the water temperature. In summary, the activities of these two lipid metabolism-related enzymes changed seasonally and the main regulating factor may be water temperature. These results provide information for determining the appropriate lipid level and fatty acid composition of the seasonal diet for cultured yellowtail.
  • Hyojin Ahn; Yasuo Agawa; Keitaro Kato
    Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 262 111075 - 111075 2021年12月
  • Mitsuki OHAMA; Kenta KISHIMOTO; Masato KINOSHITA; Keitaro KATO; Youhei WASHIO
    Borneo Journal of Marine Science and Aquaculture (BJoMSA) 4 1 28 - 35 2020年12月 
    To improve livestock and aquaculture-raised fish as food, targeted mutagenesis using genome editing technologies is becoming more realizable. Myostatin (Mstn), which functions as the negative regulator of skeletal muscle growth, is one of the major targets to improve the edible ratio of livestock and farmed fish. We previously reported that the deficiency of Pm-mstn, one of Myostatin paralogs, improves muscle growth and changes body shape in a finfish species, red seabream (Pagrus major), as a result of editing the gene by means of CRISPR/Cas9. In this study, we established Pm-mstnb-deficient red seabream, which is a null-allelic mutant of another paralogous gene of Myostatin in the species, and analyzed their phenotype in terms of growth traits and body shape. A comparison of all growth traits between Pm-mstnbwt/wt and Pm-mstnb-5/-5 revealed no significant differences. In addition, all metrics for body shape, defined as the ratios of body depth, body width, and depth of the caudal peduncle to body length, respectively, were also similar in Pm-mstnbwt/wt and Pm-mstnb-5/-5. Therefore, we concluded that Pm-mstnb does not function as a negative regulator of skeletal muscle growth in red seabream.
  • Mitsuki Ohama; Youhei Washio; Kenta Kishimoto; Masato Kinoshita; Keitaro Kato
    Aquaculture 529 735672 - 735672 2020年12月 [査読有り]
     
    © 2020 Elsevier B.V. We have reported the production of myostatin (Pm-mstn) complete knockout red sea bream (Pagrus major) using CRISPR/Cas9, and the Pm-mstn mutant exhibited a 17% increase in skeletal muscle. However, important characteristics in aquaculture production, such as the growth rate and the amount of feed required for growth have not been clarified. In this study, we conducted a feeding trial using apparent satiation feeding during the juvenile stage and compared growth performance metrics including; weight gain, feed efficiency, apparent protein and lipid retention rates of the Pm-mstn mutants with wild-type fish (WT). Experimental fish were produced via artificial insemination from single male and female broodfish of heterozygous Pm-mstn mutants and reared in one tank until the start of the trial. Genotypes of 356 full sib fish were identified, and the WT and the homozygous mutant (HM) were used for the trial. Seventeen fish from WT and HM (mean body weight 41.1 ± 0.3 g and 42.7 ± 0.3 g, respectively) were randomly distributed into each of 100 L circular tanks and set in triplicate for each genotype. Fish were fed twice daily to apparent satiation with each respective diet at 08:00 and 13:00 six days per week for 8 weeks. Weight measurement of all experimental fish was conducted bi-weekly. Five fish at day zero from each genotype and 5 fish from each tank at the final day of the trial were sampled for whole-body proximate analysis. At the end of the trial, weight gain, specific growth rate, and feed efficiency were significantly higher in the HM group than that in the WT group, and there was no significant difference in the daily feed intake. The protein efficiency and apparent protein retention were significantly higher in the HM than for the WT. These results suggest that HM fish feed similarly to that of WT fish during the juvenile stage. However, HM fish have a higher ability to convert feed efficiently and accumulate ingested protein, resulting in better overall growth.
  • Ryuichiro Aoki; Hisashi Chuda·; Youhei Washio·; Shukei Masuma·; Keitaro Kato
    Fisheries Science 86 1 57 - 64 2020年 [査読有り]
     
    © 2019, Japanese Society of Fisheries Science. The aquaculture of greater amberjack Seriola dumerili is of considerable research interest worldwide. The larviculture methods employed to culture this species, however, are still under development, and the majority of farms still rely on wild-caught juveniles. One of the problems associated with the hatchery production of this species is the optimal selection of broodstock to ensure a stable supply of high-quality eggs. Specifically, no reliable low-stress sex-discrimination technique is currently available for selecting broodstock of this species. This study investigated the efficacy of a hormone-based sex-discrimination method in full-cycle cultured S. dumerili, ranging in age from 412 to 1150 days after hatching (DAH). Plasma concentrations of the female hormone 17β-estradiol (E2) and the male hormone 11-ketotestosterone (11-KT) were measured in both spawning and non-spawning seasons, and the optimal threshold levels for sex discrimination were estimated using a receiver operating characteristic curve. Sex discrimination using E2 produced several false positives in younger fish, and had an overall accuracy of 78.7%. However, sex discrimination using 11-KT had an accuracy of 96.7%, even in 412 DAH fish. This study demonstrated that sex discrimination using 11-KT is a reliable method for optimizing the sex ratio of S. dumerili broodstock, even before the broodstock mature.
  • Residual concentration of human chorionic gonadotropin in female whitespotted conger reared under low water temperatures after a single injection
    笛田えりか; 瀬川 叡; 中村尚高; 山田伸一; 中田 久; 家戸敬太郎; 太田 博巳
    Aquaculture 509 129 - 133 2019年05月 [査読有り]
  • Sho Hosoya; Kazuharu Nomura; Keitaro Kato
    Nippon Suisan Gakkaishi (Japanese Edition) 85 2 207 - 207 2019年
  • Kishimoto, Kenta; Washio, Youhei; Murakami, Yu; Katayama, Takashi; Kuroyanagi, Miwa; Kato, Keitaro; Yoshiura, Yasutoshi; Kinoshita, Masato
    FISHERIES SCIENCE 85 1 217 - 226 2019年01月 [査読有り]
     
    Genome editing technology is becoming increasingly accepted as a way to improve traits in marine fish aquaculture. In fish, microinjection is a major method for introducing RNA or protein into eggs for genome editing; however, this method has not yet been established in aquaculture fish. We successfully established microinjection methods achieving high survival rates for tiger pufferfish and red sea bream by optimizing the following three parameters: (1) the soaking solution of fertilized eggs during microinjection, (2) the elapsed time from in vitro fertilization to microinjection, (3) the elapsed time from stripping to microinjection. In tiger pufferfish, Iwamatsu solution or diluted sea water is effective as the soaking solution. In vitro fertilization can be performed at intervals of 15min from fertilization until 2.5h after stripping. Similarly, in red sea bream, Leibovitz's L-15 medium or Iwamatsu solution is effective as the soaking solution and in vitro fertilization can be performed at intervals of 10min from fertilization until 2.5h after stripping. We anticipate our findings will contribute to effectively establish genome edited aquaculture breeds.
  • Kishimoto, Kenta; Washio, Youhei; Yoshiura, Yasutoshi; Toyoda, Atsushi; Ueno, Tomohiro; Fukuyama, Hidenao; Kato, Keitaro; Kinoshita, Masato
    AQUACULTURE 495 415 - 427 2018年10月 [査読有り]
     
    Genome editing is a powerful tool as a new breeding technology including for aquaculture because of the high efficiency of gene targeting without the requirement for exogenous gene integration. CRISPR/Cas9 system, a genome editing tool, has been widely used in various species due to its efficiency and flexibility. We demonstrate the establishment of a new breed of myostatin (Pm-mstn) complete knockout red sea bream (Pagrus major) using CRISPR/Cas9. This is the first report of the establishment of a new breed in aquaculture marine fish using genome editing. The mutations were formed by deletions in the first exon of the Pm-mstn, which cause disruption of the C-terminal active domain of MSTN. The breed exhibited a 16% increase of skeletal muscle, that is, an increase of edible parts. The breed showed the phenotype of short body length and small centrum, which is not observed in mice and other teleost fish. We established the homozygous gene disrupted breed in 2 years, which is far shorter than the conventional breeding method. Our study indicates that genome editing can accelerate the speed of aquaculture fish breeding.
  • A. Biswas; H. Araki; T. Sakata; T. Nakamori; K. Kato; K. Takii
    AQUACULTURE NUTRITION 23 6 1379 - 1389 2017年12月 [査読有り]
     
    Six isoenergetic diets were formulated as follows: fish meal (FM) 700gkg(-1) (control, C), FM 300gkg(-1) + soy protein concentrate 300gkg(-1) (SPC), FM 300gkg(-1) + enzyme-treated SPC 300gkg(-1) (ESC), FM 170gkg(-1) + soy protein isolate 300gkg(-1) (SPI), FM 160gkg(-1) + enzyme-treated SPI 300gkg(-1) (ESI) and FM 150gkg(-1) + conglycinin 300gkg(-1)(CG). Forty fish (3.9g) were randomly distributed into each of eighteen 300-L tanks, fed twice daily until satiation for 8weeks. The final body weight, specific growth rate and condition factor did not show significant differences among the fish fed with diets C, SPC, ESC and ESI (p>.05). The survival was significantly lower in fish fed with diets SPI and CG. Feed efficiency was significantly higher in fish fed with diets SPC and C than in fish fed with other diets (p<.05). There were no significant differences in nutrients retention efficiencies in fish fed with diets C, SPC, ESC and ESI. A significantly higher phosphorus retention efficiency in fish fed with soymilk protein diets resulted in lower phosphorus discharge to the environment (p<.05). These results suggest that the soymilk proteins can comfortably replace 570-770gFMkg(-1) diet of red sea bream juvenile, which will ensure significant ecological benefits through reducing phosphorus load to the environment.
  • 岸本謙太; 鷲尾洋平; 豊田 敦; 吉浦康寿; 家戸敬太郎; 木下政人
    DNA鑑定 9 45 - 50 DNA鑑定学会 2017年11月 [査読有り]
  • 岸本謙太; 家戸敬太郎; 木下政人
    水産育種 47 1 1 - 10 水産育種研究会 2017年10月 [査読有り]
  • Fui Fui Ching; Yoshizumi Nakagawa; Keitaro Kato; Shigeru Miyashita; Shigeharu Senoo
    Aquaculture Reports 3 225 - 228 2016年05月 [査読有り]
     
    The effects of delayed first feeding on the nutritional condition of tiger grouper, Epinephelus fuscoguttatus (Forsskål, 1775), larvae were examined under controlled conditions. Larval gut epithelium development and morphometric changes of the larvae fed at different first times (0, 6, 12, 18 and 24 h after mouth opening stage h AMO) were compared. Gut epithelium height (14.81 ± 0.24 μm) of larvae first fed at 0 h AMO was significantly higher (P < 0.05) compared to other treatments and gut was morphologically well developed. A continuous reduction of gut epithelium height was observed in larvae first fed beyond 0 h AMO and severe damage on connective tissue surrounding larval gut was observed in larvae fed at 24 h AMO. All morphometric growth on each body proportion of larvae first fed at 0 h AMO was gradually increased as they developed, while larvae first fed at 6, 12, 18 and 24 h AMO experienced slow development and degradation of entire body proportions. This study concludes first feeding at mouth opening stage to the tiger grouper is essential to enhance larval nutritional condition that is important to maximize larval survival and growth at subsequent stage.
  • Sang Phil Shin; Sho Shirakashi; Shogo Hamano; Keitaro Kato; Lissette Trejos Lasso; Hiroshi Yokoyama
    MOLECULAR PHYLOGENETICS AND EVOLUTION 98 337 - 345 2016年05月 [査読有り]
     
    Kudoa rayformis n. sp. (Myxozoa; Multivalvulida) was observed in the trunk muscle of Pacific sierra Scomberomorus sierra caught off the coast of Tonosi, Panama. The species formed pseudocysts in myofibers and infection was subclinical. The myxospores possessed four polar capsules and spore valves, one of which had a distinct filamentous extension. This unique morphological characteristic of the myxospore validated this as a new species of Kudoa. Genetically, K. rayformis n. sp. is closest to K. inornata, with 98% and 91% similarity in 18S and 28S rDNA, respectively, but its spore shape was clearly distinct. The 18S rDNA and concatenated sequences from K. rayformis were used in molecular phylogenetic analyses of kudoids to examine the congruence of phylogeny with infection site tropism, spore morphology and cyst/pseudocyst formation. The results demonstrated that the phenotypic traits were correlated with the phylogeny of Kudoidae, and that the biological features of K. rayformis originated from the ancient Kudoidae as exhibited by the non-specific infection site tropism and the ability to infect muscle and form pseudocysts. (C) 2016 Elsevier Inc. All rights reserved.
  • Ching Fui Fui; Akira Miura; Yoshizumi Nakagawa; Keitaro Kato; Wataru Sakamoto; Kenji Takii; Shigeru Miyashita; Shigeharu Senoo
    AQUACULTURE RESEARCH 47 1 165 - 175 2016年01月 [査読有り]
     
    The effects of different aeration rates at night to prevent sinking syndrome-related death (SSRD) of the tiger grouper, Epinephelus fuscoguttatus were examined. The aeration rates were fixed at 300 mL min(-1) at daytime (07: 00-19: 00 hours) and regulated to 0, 300 and 900 mL min(-1) at night (19: 00-07: 00 hours). Larval survival, growth, feeding intake, sinking velocity, distribution and behaviour, stress level, surface tension-related death (STRD) and flow velocity distribution were assessed. The occurrence of SSRD in the tiger grouper was observed through the accelerated sinking velocity (Vl) (from 0.15 +/- 0.09 cm s(-1) at 4 days AH to 0.41 +/- 0.09 cm s(-1) at 12 days AH) coupled with larval passive swimming behaviour at night-time. On the final day of experiment (15 days AH), larvae reared in 900 mL min(-1) at night had attained significantly higher (P < 0.05) survival (34.4 +/- 5.5%), growth (5.8 +/- 0.5 mm) and feeding intake (60.46 +/- 6.98 ind. larva(-1)). A favourable flow field for the tiger grouper was produced in 900 mL min(-1) at night-time, in which larvae were transported 15-25 cm above the tank bottom and 1.0 cm beneath the water surface. Under these night-time rearing conditions, larval stress level and number of STRD reared in 900 mL min(-1) compared with those observed in 300 mL min(-1) remained insignificant, indicating that strong turbulence of flow velocity was not detrimental for larvae. Our findings recommend aeration at 900 mL min(-1) at night as this could improve larval survival by reducing SSRD.
  • Michitaka Yamamoto; Kazuhiro Sugahara; Makoto Endo; Katsuya Ishimaru; Keitaro Kato
    Fish Pathology 50 3 97 - 104 2015年 [査読有り]
     
    We studied the epidemiology of Flavobacterium psychrophilum in ayu from Lake Biwa for establishing control measures to bacterial cold water disease (BCWD). During 1998-2011, 12,743 wild ayu were collected from coastal (set net and gill net), offshore (offshore scoop net) and inflow river (fishing weir) areas of Lake Biwa. We employed a nested-PCR technique targeting 16S rRNA gene for the detection of F. psychrophilum in the gills and kidney of ayu. Prevalence of the bacterium was greatest when the water temperature of Lake Biwa was 18-21°C, which coincides with the optimum temperature for multiplication of F. psychrophilum. The prevalence of F. psychrophilum in the gills was higher in fish from fishing weirs and set nets maintained in net cages than in fish just after catch with the other fishing techniques. This suggests that rearing ayu in net cages at high densities following catch by fishing weirs and set nets can advance infection with the bacterium among the captured fish which will be used for seedlings in aquaculture or releasing in rivers. Control measures for the captured ayu must be conducted in reliable ways to prevent spread of the disease after release and in aquaculture.
  • Hirofumi Ohga; Hayato Adachi; Kojiro Matsumori; Ryoko Kodama; Mitsuo Nyuji; Sethu Selvaraj; Keitaro Kato; Shinji Yamamoto; Akihiko Yamaguchi; Michiya Matsuyama
    COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY 179 104 - 112 2015年01月 [査読有り]
     
    Kisspeptin (Kiss) and its cognate receptor (Kiss1R), implicated in the neuroendocrine control of GnRH secretion in mammals, have been proposed to be the key factors in regulating puberty. However, the mechanisms underlying the initiation of puberty in fish are poorly understood. The chub mackerel Scomber japonicus expresses two forms of Kiss (kiss1 and kiss2) and two Kiss receptor (kissr1 and kissr2) genes in the brain, which exhibit sexually dimorphic changes during the seasonal reproductive cycle. This indicates that the kisspeptin system plays an important role in gonadal recrudescence of chub mackerel; however, the involvement of the kisspeptin system in the pubertal process has not been identified. In the present study, we examined the mRNA expression of kiss1, kiss2, kissr1, kissr2, and gnrh1 (hypophysiotropic form) in the brain of a chub mackerel during puberty. In male fish, kiss2, kissr1 and kissr2 levels increased significantly at 14 weeks post-hatch (wph), synchronously with an increase in type A spermatogonial populations in the testis; kiss2 and gnrh1 levels significantly increased at 22 wph, just before the onset of meiosis in the testes. In female fish, kiss2 increased significantly at 14 wph, synchronously with an increase in the number of perinucleolar oocytes in the ovary; kiss1 and kiss2 levels significantly increased concomitantly with an increase in the kissr1, kissr2, and gnrh1 levels at 24 wph, just before the onset of vitellogenesis in oocytes. The present results suggest positive involvement of the kisspeptin-GnRH system in the pubertal process in the captive reared chub mackerel. (C) 2014 Elsevier Inc. All rights reserved.
  • Goshi Kato; Keitaro Kato; Walissara Jirapongpairoj; Hidehiro Kondo; Ikuo Hirono
    FISH PATHOLOGY 49 4 165 - 172 2014年12月 [査読有り]
     
    This study presents the development of DNA vaccines against nocardiosis, using the Antigen 85-like (Ag85L) gene in Nocardia seriolae. An expression plasmid encoding Ag85L (pAg85L(wt)) and codon-optimized Ag85L (pAg85L(opt)) was intramuscularly injected into amberjack Seriola dumerili. Survival rates of the pAg85L(wt), pAg85L(opt) vaccinated group and PBS-injected group as a negative control were 88%, 98% and 51%, respectively, at 40 days after the N. seriolae challenge. In addition, the N. seriolae bacterial count in the spleen was significantly lower in the pAg85L(wt) and pAg85L(opt) vaccinated fish than in the PBS-injected fish (P < 0.05). These results suggest that the DNA vaccines pAg85L(wt) and pAg85L(opt) conferred protective efficacy against N. seriolae infection in amberjack.
  • Sharifah Rahmah; Keitaro Kato; Shinji Yamamoto; Kenji Takii; Osamu Murata; Shigeharu Senoo
    AQUACULTURE RESEARCH 45 12 2000 - 2009 2014年11月 [査読有り]
     
    Manipulation of stocking densities (10, 20, 30, 40 and 50 larvae L-1), each with or without the presence of shelter was conducted to determine the effects on survival, cannibalism and growth performances of larval bagrid catfish Mystus nemurus (Valenciennes 1840) from 2 to 14 days after hatching. This study revealed that stocking density significantly affected survival, cannibalism, total length, feed intake, specific growth rate and final weight of bagrid catfish larvae. Significantly higher survival was observed at moderate stocking density of more than 20 but less than 50 larvae L-1. Survival was significantly low beyond this threshold and was the lowest at 10 larvae L-1, coincides with the highest cannibalism. Total length, feed intake, specific growth rate and final weight were significantly higher at 10 larvae L-1. Shelter significantly improved total length and feed intake. No significant effects of stocking density and shelter were observed on the apparent feed conversion ratio and coefficient of variation. There was also no significant interaction between stocking density and shelter in all parameters. This study suggests that bagrid catfish larvae could be cultured at more than 20 but less than 50 larvae L-1 with the availability of shelter for optimal larviculture condition.
  • Keitaro Kato; Masato Yamamoto; Khaoian Peerapon; Haruhisa Fukada; Amal Biswas; Shinji Yamamoto; Kenji Takii; Shireru Miyashita
    AQUACULTURE RESEARCH 45 11 1818 - 1824 2014年10月 [査読有り]
     
    Taurine is often added to artificial fish diets to compensate for a reduction in fish meal (FM). However, the taurine content of FM-based diets is typically lower than in diets consisting of raw fish, even in diets where FM is the only protein source. We evaluated the effects of dietary taurine in FM-based diets on epidermal thickness and scale detachability in red sea bream Pagrus major. We compared the effect of diets containing 0% (control), 0.3% (Tau-0.3%), 0.6% (Tau-0.6%) and 1.0% (Tau-1.0%) taurine. Red sea bream (average body weight, 39 g) were fed these diets for 7 weeks. Taurine supplementation had no effect on growth, feed intake, feeding efficiency, or survival. However, the epidermal thickness was higher in fish in the Tau-0.6% and Tau-1.0% groups than in the control and Tau-0.3% groups. Similarly, scale loss was significantly higher in the control group than in the Tau-0.6% and Tau-1.0% groups. Our results suggest that supplementation with > 0.6% taurine (1.0% in diet) improves skin condition.
  • Mitsuo Nyuji; Ryoko Kodama; Keitaro Kato; Shinji Yamamoto; Akihiko Yamaguchi; Michiya Matsuyama
    ZOOLOGICAL SCIENCE 31 6 398 - 406 2014年06月 [査読有り]
     
    Understanding puberty is important for establishing aquaculture in fish. In this study, we analyzed the timing and completion of pubertal development along with changes in pituitary gonadotropin genes (fshb and lhb) in cultured chub mackerel (Scomber japonicus). At 45 days post-hatching (dph), gonadal sex differentiation was observed. The onset of puberty occurred at 192 dph in females with the start of vitellogenesis, whereas it occurred at 164 dph in males, with the beginning of spermatogenesis (proliferation and differentiation of germ cells). The completion of puberty was at 326 dph in females when vitellogenesis completed, and it was at 338 dph in males during spermiation. All fish sampled during the spawning season completed pubertal development. In the pituitary of female fish, fshb expression was activated during early secondary growth and was maintained high throughout vitellogenesis, whereas lhb expression was highest at the completion of vitellogenesis. In male fish, fshb and lhb expression were activated from the onset of spermatogenesis and further activated during late pubertal development; fshb remained high between late spermatogenesis and spermiation, whereas lhb was highest during spermiation.
  • Ching Fui Fui; Akira Miura; Yoshizumi Nakagawa; Keitaro Kato; Shigeharu Senoo; Wataru Sakamoto; Kenji Takii; Shigeru Miyashita
    AQUACULTURE RESEARCH 45 5 874 - 881 2014年04月 [査読有り]
     
    Flow field control via aeration adjustment for the enhancement of larval survival of the kelp grouper Epinephelus bruneus was examined. Aeration rate of 300mLmin(-1) was introduced during daylight (07:00-19:00hours) and adjusted to 0, 300 and 900mLmin(-1) at night (19:00-07:00 hours). Larval sinking velocity +/- SD increased from 0.08 +/- 0.05 to 0.26 +/- 0.24cmsec(-1) from 4 to 12days after hatching (DAH), indicating their susceptibility to sink. Larvae reared in 300mLmin(-1) attained the highest survival rate at 24.9 +/- 3.4%, but remained significantly smaller in growth: 4.54 +/- 0.56mm compared with 4.82 +/- 0.53mm in 900mLmin(-1). The flow field in 300 and 900mLmin(-1) was at 10-20 and 15-25cm above the bottom of the tank and 8.0 and 1.0cm beneath the water surface. A favourable rearing condition was observed in 300mLmin(-1) as larvae were away from the bottom and surface areas, thus preventing them from dying due to sinking and surface tension-related death (STRD). Although sinking death was decreased with an increasing aeration rate, the stronger flow had increased larval susceptibility to STRD. Our findings suggest that aeration at 300mLmin(-1) could enhance larval survival by reducing both sinking death and STRD.
  • Sharifah Rahmah; Keitaro Kato; Shinji Yamamoto; Kenji Takii; Osamu Murata; Shigeharu Senoo
    AQUACULTURE RESEARCH 45 3 501 - 508 2014年02月 [査読有り]
     
    Manipulation of photoperiod: 24h light (24L), 12h light:12h dark (12L:12D) and 24h dark (24D); and feeding schedules: day and night feeding (DNF), day feeding (DF) and night feeding (NF) was conducted to determine effects on survival, cannibalism and growth of larval bagrid catfish Mystus nemurus 2-14days after hatching (dAH). Photoperiod insignificantly affected all parameters. Feeding schedule significantly affected survival and total length at 6 (P<0.049; P<0.009), 10 (P<0.033; P<0.000) and 14 dAH (P<0.013; P<0.000), respectively, but affected cannibalism at 10 (P<0.043) and 14 dAH (P<0.013). Survival for DNF was significantly higher than DF. Cannibalism for DNF was significantly lower than NF at 10 and 14 dAH. Total length for DNF was significantly higher than DF and NF at 10 and 14 dAH. At 14 dAH, feeding schedule significantly affected feed intake, final weight and coefficient of variation. For feed intake and final weight, DNF was significantly higher than DF and NF. For coefficient of variation, NF was significantly higher than DF. This study suggests that larval bagrid catfish can be reared at 24L, 12L:12D or 24D but should be fed day and night for improved growth, survival and reduced cannibalism.
  • 家戸 敬太郎; 澤田 好史; 岡田 貴彦; 倉田 道雄; 向井 良夫; 宮下 盛; 村田 修; 熊井 英水
    化学と生物 51 4 257 - 262 Japan Society for Bioscience, Biotechnology, and Agrochemistry 2013年04月
  • Tohya Yasuda; Kazuyoshi Komeyama; Keitaro Kato; Yasushi Mitsunaga
    FISHERIES SCIENCE 78 2 229 - 235 2012年03月 [査読有り]
     
    We investigated the usefulness of acceleration loggers in aquaculture by examining net-cage use and metabolic rates in red sea bream, Pagrus major. First, the fish's metabolic rate (mg O-2 kg(-1) min(-1)) was measured with the logger in a swim tunnel at designated water velocities. We found that metabolic rate could be expressed by using a linear regression model of the activity rate index (unitless min(-1)) derived from acceleration data. Using this equation, the field metabolic rates of three fish in a net cage were monitored and were estimated at 14.1-15.0 kcal kg(-1) day(-1). The results suggested that 15-19% of energy from satiation feeding ration was consumed for metabolism and activity in the net cage. The loggers showed orderly net-cage use by the fish. Tagged individuals used the whole cage from surface to bottom, but individual fish that preferred the surface area rarely used the bottom, and vice versa. Metabolic rate increased significantly with distance of the fish from their preferred depths. The logger provided information on the physiological and behavioral responses of fish in a given breeding system, and its use should contribute to the design of practical aquaculture systems.
  • 家戸 敬太郎; 山本 將人; Nguyen Phuc Hung; 深田 陽久; Amal Biswas; 山本 眞司; 滝井 健二; 村田 修; 宮下 盛
    水産増殖 = The aquiculture 60 1 59 - 64 水産増殖談話会 2012年03月 [査読有り]
     
    低魚粉配合飼料に対するタウリン添加に関する報告は多い。しかし，魚粉のみをタンパク質源とした飼料においても，配合飼料のタウリン含有量は生餌に比べると低い。そこで本研究では，マダイ Pagrus major の皮膚の厚さおよび脱鱗しやすさに及ぼすタウリンの添加効果を，低魚粉仕様ではない市販の配合飼料（魚粉含量57%）を用いて検討した。タウリンの添加レベルを0%（対照区），1%添加区（Tau-1%）および2%添加区（Tau-2%）の3段階とした。マダイ（平均体重107 g）にこれらの飼料を60日間投与した。本実験条件下では成長および飼料効率には区間差はみられなかった。しかしながら，Tau-1%および Tau-2%の皮膚の厚さは対照区よりも有意に厚く，対照区は Tau-1%および Tau-2%よりも有意に脱鱗しやすかった。これらの結果は，市販配合飼料へのタウリン添加は，成長などへの効果はほとんどないが，マダイの皮膚の状態を著しく向上させることが示唆された。
  • 阮 秀英; 中川 至純; 白樫 正; 家戸 敬太郎; 村田 修; 滝井 健二; 宮下 盛; 瀬尾 重治
    水産増殖 = The aquiculture 60 1 1 - 9 水産増殖談話会 2012年03月 [査読有り]
     
    東南アジアにおいて重要な淡水養殖魚であるマーブルゴビ Oxyeleotris marmoratus の孵化率向上のため，マレーシア・サバ州の河川で捕獲されたマーブルゴビから得た卵を，淡水（FW），5，10，15，20および30 psu に希釈した海水（SW）でインキュベートし，孵化率および仔魚の奇形率を調べた。その結果，淡水から15 psu SW の間で正常孵化がみられ，10 psu SW において最も孵化率が高く奇形率が低かった。そこで FW と10 psu SW との間で孵化時期および10日齢の仔魚の生残率を比較したところ， FW では10 psu SW よりも孵化が遅れ，遅れて孵化した仔魚の奇形率は高く，さらに FW では全ての仔魚が10日齢までに斃死した。本実験の結果から，本実験で用いた卵を10 psu SW でインキュベートすると FW よりも孵化時期が早く，孵化率および仔魚の生残率が高くなることがわかった。
  • Osamu Murata; Keitaro Kato
    NIPPON SUISAN GAKKAISHI 78 2 265 - 265 2012年03月 [査読有り]
  • Fui Fui Ching; Yoshizumi Nakagawa; Keitaro Kato; Osamu Murata; Shigeru Miyashita
    AQUACULTURE RESEARCH 43 2 303 - 310 2012年01月 [査読有り]
     
    The effects of delayed first feeding on the survival and growth of tiger grouper, Epinephelus fuscoguttatus (Forsskal 1775), larvae were examined under controlled conditions. The total length, yolk sac volume, oil globule volume, yolk sac absorption time and nutritional transition period (NTP) of the larvae fed at different first times (0, 6, 12, 18 and 24 h after the mouth opening stage; h AMO) were compared. Larval first feed intake was observed at 54 h after hatching (h AH) at 27.5 +/- 0.5 degrees C. The yolk sac was consumed more rapidly with an increase in delayed first feeding and was significantly different among treatments (P<0.05). Larvae first fed at 0 h AMO had the longest yolk sac absorption (72 h AH) and NTP (20 h) times and had the highest survival and growth rates at the end of the experimental period (360 h AH), being significantly higher (P<0.05) than the other treatments. First mortality was observed at 69 h AH, approximately 2 h after point of no return (PNR) occurred. This study suggests that first feeding of tiger grouper larvae should commence at 0 h AMO for enhancement of larval survival and growth.
  • Sharifah RAHMAH; Shinji YAMAMOTO; Yoshizumi NAKAGAWA; Keitaro KATO; Shigeharu SENOO; Osamu MURATA
    Aquaculture Sci. 59 3 443 - 450 2011年09月 [査読有り]
  • Hou Chew Ha; Shigeharu Senoo; Kazunobu Tsunemoto; Yoshizumi Nakagawa; Shigeru Miyashita; Osamu Murata; Keitaro Kato
    Aquaculture Sci. 59 3 383 - 391 2011年09月 [査読有り]
  • Goshi Kato; Keitaro Kato; Kei Saito; Yo Pe; Hidehiro Kondo; Takashi Aoki; Ikuo Hirono
    FISH & SHELLFISH IMMUNOLOGY 30 2 467 - 472 2011年02月 [査読有り]
     
    Mycobacteriosis, caused by the intracellular parasitism Mycobacterium sp., causes economic damages to aquaculture production in Japan, particularly in seriola fish production. Antibiotics are not effective against Mycobacterium sp. and so a potent vaccine is needed. We previously reported that BCG vaccine (Mycobacterium bovis BCG) induces adaptive immunity against Mycobacterium sp. in Japanese flounder, Paralichthys olivaceus. In a phylogenetic tree, the genes for a major antigen, the Ag85 complex, in Mycobacterium sp. TUMSAT-Msp001 are closely related to homologues in Mycobacterium ulcerans. M. bovis BCG was detected until 7 days post-injection at the injection site (muscle) and 28 days post-vaccination in spleen. Cumulative mortality of amberjack, Seriola dumerili vaccinated intramuscularly (i.m.) and intraperitoneally (i.p.) with M. bovis BCG was 32.3% and 59.5% respectively, at 24 days post-infection of Mycobacterium sp., compared to 97.8% in PBS-injected fish. The bacterial counts of Mycobacterium sp. in spleen of both i.m.-and i.p.-vaccinated fish (6.2 x 10(3) and 1.3 x 10(4) CFU/mg tissue, respectively) at 20 days post-infection were significantly lower (P < 0.01) than those of PBS-injected fish (8.0 x 10(6) CFU/mg). Furthermore, Immersion challenge with Mycobacterium sp. TUMSAT Msp-001 showed 50% RPS value in BCG i.m.-vaccinated fish at the end of the experiment. These results support our previous study using Japanese flounder and suggest that BCG vaccine is also effective against Mycobacterium sp. infection in amberjack. (C) 2010 Elsevier Ltd. All rights reserved.
  • 家戸 敬太郎
    日本水産學會誌 = Bulletin of the Japanese Society of Scientific Fisheries 76 4 742 - 742 The Japanese Society of Fisheries Science 2010年07月
  • 足立亨介; 家戸敬太郎
    水産増殖 58 2 181 - 187 水産増殖談話会 2010年06月 [査読有り]
     
    明暗の度合いを示す指標であるL＊を評価基準として、マダイ種苗出荷前50日間の遮光処理が体色に与える影響を検討した。出荷前50日間の遮光は出荷時の体色に影響を与えず、この時期に遮光飼育されなかったことが原因で後になって特別に体色が黒くなるということもない。種苗出荷後に紫外線の影響で黒くなったとしても適切に遮光飼育すれば体色の改善効果においても稚魚期に遮光飼育した群と比した差をなくすことは可能である。
  • Kohsuke Adachi; Kazumasa Wakamatsu; Shosuke Ito; Hajime Matsubara; Kazuharu Nomura; Hideki Tanaka; Keitaro Kato
    Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology 156 2 184 - 189 2010年06月 [査読有り]
     
    Male and female teleost seabream (Pagrus major) were examined for seasonal variation of eumelanin, pheomelanin, 11-ketotestosterone (11KT, fish androgen), lightness (L* value) and Gonad Somatic Index (GSI: gonad mass / body mass × 100). In males, levels of pyrrole-2,3,5-tricarboxylic acid (a marker of eumelanin), 11KT and the GSI increased sharply from September and plateaued in March and April when the fish are sexually mature. These results are consistent with the lightness of their body color. Using the data from males, a high correlation was observed for all combinations of those four variables (PTCA, 11KT, lightness and GSI). In females, little change was observed in those variables except for the GSI. 4-Amino-3-hydroxyphenylalanine (a marker of pheomelanin) was also analyzed, but it was below the detection limit at all times. Oral treatment of juvenile red seabream with synthetic androgen methyl-testosterone for 2 months induced eumelanin accumulation about 3 times higher than the control. These data show that there is a close relationship between androgen levels and eumelanin accumulation in teleosts. This is the first report that androgen affects melanin accumulation in a dose-dependent manner. © 2010 Elsevier Inc. All rights reserved.
  • Kagayaki Morishima; Hiroshi Yamamoto; Yoshifumi Sawada; Shigeru Miyashita; Keitaro Kato
    MOLECULAR ECOLOGY RESOURCES 9 3 790 - 792 2009年05月 [査読有り]
     
    Twenty-three new polymorphic microsatellite markers were isolated in the Pacific bluefin tuna, Thunnus orientalis. Each locus comprised three to 34 alleles. The expected and observed heterozygosities ranged between 0.46 and 0.96 and between 0.44 and 0.97, respectively. The Kto9, Kto11, and Kto42 markers demonstrated significant deviation from Hardy-Weinberg equilibrium; high null allele frequencies (0.08-0.14) were observed in the deviating group. From the results of simulation of parentage assignment, a combination of four loci (i.e. Kto15, Kto23, Kto38, and Kto39) was considered the best for parentage assignment.
  • Tatsuo Miyamoto; Akihiro Momoi; Keitaro Kato; Hisato Kondoh; Shoichiro Tsukita; Mikio Furuse; Makoto Furutani-Seiki
    CELL AND TISSUE RESEARCH 335 2 465 - 471 2009年02月 [査読有り]
     
    The tight junction (TJ) is a specialized cell-cell adhesion structure in epithelial and endothelial sheets unique to the chordates and functions as a barrier of fluidal diffusion across the cell sheets. In order to study the dynamics of TJ formation in vivo during embryogenesis, we have generated a transgenic medaka line that expresses claudin-7 protein fused to enhanced green fluorescent protein under the regulation of the red seabream beta-actin promoter in transparent medaka embryos. Claudins contain four transmembrane domains and have been identified as the key molecules that dictate the function of TJs. This transgenic medaka line will thus be useful for imaging of TJs in living embryos and hence in screening for mutations affecting cell-cell adhesion.
  • Molecular cloning and daily mRNA levels of prolactin and somatolactin in aquacultured Pacific bluefin tuna (Thunnus orientalis)
    Kohsuke Adachi; Keitaro Kato; Masayoshi Yamamoto; Katsuya Ishimaru; Toru Kobayashi; Osamu Murata; Hidemi Kumai
    Aquaculture 296 1-2 110 - 116 2009年 [査読有り]
  • Kohsuke Adachi; Keitaro Kato; Masayoshi Yamamoto; Katsuya Ishimaru; Toru Kobayashi; Osamu Murata; Hidemi Kumai
    AQUACULTURE 281 1-4 158 - 161 2008年09月 [査読有り]
     
    The daily expression profile of growth hormone (GH) mRNA in juvenile Pacific bluefin tuna (Thunnus orientalis) was investigated under aquacultured conditions. Total RNA from pituitaries (n=5) was sampled from 10 am to 12 pm the next day at 1 h intervals. The expression levels of GH mRNA were evaluated using real-time PCR normalized against the beta-actin gene. The expression level of GH transcripts reached a peak at 3-4 am at which time it was about 10 times higher than at any other time period. Considering their high growth rate compared to red seabream (Pagrus major) and other aquacultured species which shows continuous CH mRNA expression patterns, it can be concluded that the pulsed expression of GH mRNA just before daybreak is a key for the extremely high somatic growth rate of Pacific bluefin tuna. (C) 2008 Elsevier B.V. All rights reserved.
  • Yoshifumi Sawada; Manabu Seoka; Keitaro Kato; Toshihiro Tamura; Masahiro Nakatani; Shoji Hayashi; Tokihiko Okada; Kenichi Tose; Shigeru Miyashita; Osamu Murata; Hidemi Kumai
    FISHERIES SCIENCE 73 5 1070 - 1077 2007年10月 
    Stable reproduction is essential for supplying artificially hatched fish to tuna aquaculture. We observed testes maturation in reared Pacific bluefin tuna (PBT) Thunnus orientalis at 2+ years of age. The incidence of males with mature testes was 25.0%, and 40% of the males had developing testes that contain spermatozoa, while oocytes of the same aged females were not mature. These fish were wild-caught at 0+ years old in August 1997 and the gonads were examined in October 1998 and January-February 2000. Therefore, the age at examination in 2000 was estimated to be 2 years and 7-10 months old considering the spawning season of the wild PBT and the size when captured. Histological examination of the matured and developing testes showed that they contained spermatozoa, spermatids, spermatocytes, and spermatogonia. All the spermatozoa were observed to be motile in sea water under light microscopy. From the results of this and previous studies, matured males are probably fertile for at least 5 months a year in Kushimoto. The testes maturation observed at young age in captivity is considered promising to reduce the cost of broodstock maintenance for the juvenile production of PBT, especially if the sperm are cryopreserved.
  • Keitaro Kato; Masayoshi Takagi; Yutaka Tamaru; Shin-ichi Akiyama; Takafumi Konishi; Osamu Murata; Hidemi Kumai
    Fisheries Science 73 2 440 - 445 2007年04月 
    Transgenic technology has been widely applied to a variety of freshwater fish species. However there are few reports on the use of this technology in commercially important marine species. In this study, the construction of expression vectors containing the beta-actin promoter region for use in the red sea bream Pagrus major, a species of considerable importance to the aquaculture industry in Japan is reported. The beta-actin gene was cloned from a red sea bream genomic DNA library. Recombinant plasmids were constructed by linking the 5' flanking region of the beta-actin gene to the green fluorescent protein reporter gene, followed by the poly A signal sequence of simian virus 40 or the 3' flanking region the beta-actin gene. Expression of these constructs was examined following microinjection into zebrafish and red sea bream embryos, and compared to that of the expression vector pXI-GFP driven by the Xenopus elongation factor la. The results indicated that the construct consisting of the beta-actin 5'-and 3' flanking regions was the most efficacious. In future studies, it is planned to investigate the efficient condition for integration into chromosomes of the transgene.
  • 瀬岡 学; 家戸 敬太郎; 久保 敏彦; 向井 良夫; 坂本 亘; 熊井 英水; 村田 修
    水産増殖 55 2 289 - 292 日本水産増殖学会 2007年 
    近畿大学水産研究所奄美実験場で養成したクロマグロの生殖腺の発達状況を調べた。生殖腺の組織学的観察結果から, 雄個体は2～3歳で成熟し, 雌個体は4歳から産卵することが示された。また, 雌雄ともに生殖腺指数は6月に高く, 4歳魚では約3%に達する個体が出現した。養成クロマグロの成熟は, 飼育環境における水温上昇と長日化により促進されると思われる。
  • Yutaka Tamaru; Masanori Ohtsuka; Keitaro Kato; Sadao Manabe; Kouichi Kuroda; Mitsuaki Sanada; Mitsuyoshi Ueda
    BIOTECHNOLOGY PROGRESS 22 4 949 - 953 2006年08月 
    The cell surface is a functional interface between the inside and the outside of the cell. Moreover, cells have systems for anchoring surface specific proteins and for confining surface proteins to particular domains on the cell surface. For use in bioindustrial processes applied to oral vaccination, we consider that cell-surface display systems must be useful and that the yeast Saccharomyces cerevisiae, the most suitable microorganism for practical purposes, is available as a host for genetic engineering because it can be subjected to many genetic manipulations. In particular, the rigid structure of the cell makes the yeast suitable for several of the applications. In this study, we describe the expression of one of the target antigens, 380R, from the red sea bream iridovirus (RSIV), which is one of the most common viral diseases in the cultured marine fish Pagrus major in Japan, using the arming yeast system and aiming at its application for oral vaccination. We first performed the molecular cloning and expression of the 380R antigen from RSIV in Escherichia coli. The nucleotide sequence of the 380R antigen was composed of an open reading frame (ORF) of 1360 bp encoding a protein of 453 residues. To prepare a specific antibody against the 380R antigen, the recombinant protein was overexpressed and purified in E. coli. As a result of indirect immunofluorescence with the specific antibody, we could observe the expression of the 380R antigen on the surface of the yeast cells. Thus, we have successfully prepared the source of an oral vaccine using cell-surface display technology in yeast.
  • Y Sawada; M Hattori; N Sudo; K Kato; Y Takagi; K Ura; M Kurata; T Okada; H Kumai
    AQUACULTURE RESEARCH 37 8 805 - 812 2006年06月 [査読有り]
     
    A previous study elucidated that an extreme hypoxia during somitogenesis induced the most frequent skeletal malformation centrum defects in red sea bream (RSB), Pagrus major. In this study, details of the hypoxic conditions to induce them in RSB, dissolved oxygen (DO) concentration and exposure time to hypoxia, were investigated. Fertilized eggs were exposed to seawater of six DO concentrations (0%, 10%, 25%, 50%, 75% and 100% of saturation) for seven different periods (5, 10, 30, 60, 120, 240 and 360 min) during somitogenesis. Somitic disturbances in newly hatched larvae were induced by exposure to 0% and 10% DO concentration for 10 and 120 min and longer respectively. Rearing eggs exposed to hypoxic condition of 10% DO for 240 min for 40 days post-hatch showed that the location and the frequency of somitic disturbances in larvae and centrum defects in juveniles were significantly correlated (P < 0.01). Dissolved oxygen concentration of the interstitial water in the egg high density layer formed at the water surface in a stationary state abruptly decreased to 3.7% within 7 min. Centrum defect induction by exposure of eggs to extreme low DO concentrations for a short period, which is the probable situation in the practical juvenile production, suggests that careful maintenance of DO concentration is important in the incubating water of fertilized eggs during egg sorting and transportation, where eggs are made into a pile and undergo hypoxia, for the prevention of centrum defects.
  • 熊井 英水; 村田 修; 山本 眞司; 家戸 敬太郎; 宮下 盛
    水産増殖 2006 54 195 - 200 日本水産増殖学会 2006年 
    天然養成マサバの成長と生殖腺発達状況を調べた。供試魚は地先網生簀に収容し, 5～30日間隔で全長, 尾叉長, 体長, 体高および体重測定を行った。実験開始時の平均尾叉長は10.5±0.8cmで平均体重は11.0±2.9gであった。1歳魚の12月の時点で, 商品サイズの目安となる300gを上回った。実験終了時の尾叉長は32.1±1.7cmとなり, 平均体重は396.7±94.9gに成長した。次に, 地先網生簀より15日から30日間隔で雄雌それぞれ20尾ずつ取り上げて生殖腺重量を測定してGSIおよびKGを算出した。1歳魚雌個体のKGは2月後半から上昇を始め, 5月下旬に最大となった。それ以降は減少し, 8月には増加を始める以前とほぼ同様の水準となった。2歳魚のKGは1月から上昇を始め, 3月に産卵の目安となる5.0を越えた。それ以降6月下旬まで5.0以上を保ったが, 7月に入ると急激に減少し, 8月には前年11月と同じ水準となった。海上生簀で飼育した2歳魚の一部を, 3月から6月に陸上施設で飼育したところ, 5月2日 (日齢729日) 以降ほぼ毎日産卵が確認された。
  • 足立亨介; 家戸敬太郎; 若松一雅; 伊藤祥輔; 石丸克也; 村田修; 熊井英水
    水産増殖 54 1 31 - 35 日本水産増殖学会 2006年 [査読有り]
     
    低水温がマダイ稚魚に与える影響について検討した。10℃で低温飼育されたマダイは有意に黒変する。血液検査では対照区と大きな差は見られなかった。近畿大学水産研究所で冬季に出現する黄化個体の原因はビリルビンでもフェオメラニンでもない。また単なる低温飼育のみでは黄化個体は出現しないことから, 低温以外に何らかの要因がその誘発には必要であると考えられる。黄化個体は対照区と比べ, 動きが遅いため何らかの疾患の影響が予想される。経験的に黄化マダイは黒変していくことが知られるが, その原因は疾病によるストレスによるものと推察される。
  • Kohsuke Adachi; Keitaro Kato; Kazumasa Wakamatsu; Shosuke Ito; Katsuya Ishimaru; Takashi Hirata; Osamu Murata; Hidemi Kumai
    Pigment Cell Res. 18 6 465 - 468 2005年12月 
    Human melanocytes respond to UV irradiation by increasing the synthesis of melanin. While much is now understood of the pathways governing this process and the nature of the melanin synthesized, little is known of melanins produced by lower vertebrates and their capacity to respond to UV. Here we report that a fish, red seabream, can undergo 'suntanning'. Histological, colorimetric and chemical assays were performed for suntanned red seabream fish bred in net cages to analyse the melanins and compared with shaded or wild red seabream fish. For color evaluation, the L* values of suntanned fish were dramatically lower than those in the other two groups. Pyrrole-2,3,5-tricarboxylic acid (PTCA), an indicator of eumelanin, was detected in suntanned fish at five times higher levels than in shaded or wild fish while 4-amino-3-hydroxyphenyl-alanine (4-AHP), a marker for pheomelanin, could not be detected in any of the samples. Histological analysis showed that melanocytes in the suntanned skin enlarged and increased in number to form a monolayer at the surface of the skin. Analysis of L* values and PTCA levels showed quite a high correlation coefficient (r = -0.843). When comparing shaded and wild red seabream fish, the scores were closer but some significant differences were still found in some body areas. These results indicate that eumelanin accumulates in suntanned fish during the increase in skin color, which is induced by sunlight, presumably by ultraviolet radiation.
  • Takafumi Konishi; Keitaro Kato; Toshiyoshi Araki; Kentaro Shiraki; Masahiro Takagi; Yutaka Tamaru
    Biochemical Journal 388 1 299 - 307 2005年05月 
    To elucidate drug deposition and metabolism in cultured marine fishes, in a previous study we isolated and purified the GSTs (glutathione S-transferases) from the hepatopancreas of the red sea bream Pagrus major that contained 25 and 28 kDa GST subunits. The 25 kDa GST subunits encoded by two genes (GSTA1 and GSTA2) have been identified as Alpha-class GSTs. In the present study, we performed the molecular cloning and characterization of the GSTR1 gene encoding the 28 kDa GST subunit from the Pa. major hepatopancreas. The nucleotide sequence of GSTR1 was composed of an ORF (open reading frame) of 675 bp encoding a protein of 225 residues with a predicted molecular mass of 25.925 Da. A search of the BLAST protein database revealed that the deduced amino acid sequence of GSTR1 was structurally similar to that of GSTs derived from other fishes such as largemouth bass (Micropterus salmoides) and plaice (Pleuronectes platessa). The genomic DNA containing the GSTR1 gene was found to consist of six exons and five introns quite distinct from mammalian Theta-class GSTs. We have purified and characterized the recombinant GSTR1 enzyme (pmGSTR1-1) which showed activity only towards 1-chloro-2,4-dinitrobenzene, although it had no detectable activity towards cumene hydroperoxide, 1,2-dichloro-4-nitrobenzene, ethacrynic acid, 4-hydroxynonenal and p-nitrobenzyl chloride. Moreover, pmGSTR1-1 revealed remarkable heat instability (melting temperature T m = 30.3 ± 0.11°C). Collectively, our results indicated that the characteristic GST genes including GSTR1 have been conserved and functional in fishes. Therefore we designate them 'Rho-class', a new class of GSTs. © 2005 Biochemical Society.
  • Takafumi Konishi; Keitaro Kato; Toshiyoshi Araki; Kentaro Shiraki; Masahiro Takagi; Yutaka Tamaru
    Comparative Biochemistry and Physiology - C Toxicology and Pharmacology 140 3-4 309 - 320 2005年03月 
    Two distinct cDNAs corresponding to GSTA1 and GSTA2 genes encoding glutathione S-transferases (GSTs) from the hepatopancreas of red sea bream, Pagrus major were cloned and sequenced. A comparison of the nucleotide sequences of GSTA1 and GSTA2 revealed 98% identity and their derived amino acid sequences had 96% similarity. Both genes could be classified as α-class GSTs on the basis of their amino acid sequence identity with other species. Genomic DNA cloning showed that both GSTA1 and GSTA2 genes consisted of six exons and five introns. In a comparison of genomic DNAs, the structures of GSTA1 and GSTA2 differed. In addition, Southern-blot analysis indicated that at least two kinds of α-class GSTs existed in the P. major genome. In order to biochemically characterize the recombinant enzymes (pmGSTA1-1 and pmGSTA2-2), both clones were highly expressed in Escherichia coli. The purified pmGSTA1-1 and pmGSTA2-2 exhibited glutathione conjugating activity toward 1-chloro-2,4-dinitrobenzene and glutathione peroxidase activity toward cumene hydroperoxide, while neither pmGSTs show detectable activity toward 1,2-dichloro-4-nitrobenzene, ethacrynic acid, 4-hydroxynonenal, or p-nitrobenzyl chloride. Despite their high level of amino acid sequence identity, the pmGSTs had quite different enzyme-kinetic parameters. © 2005 Elsevier Inc. All rights reserved.
  • 村田 修; 山本 眞司; 石橋 亮; 岡 佑介; 米島 久司; 家戸 敬太郎; 宮下 盛; 熊井 英水
    水産増殖 53 3 319 - 324 日本水産増殖学会 2005年 
    人工孵化マサバ3歳魚について産卵状況を調べた。供試魚は円形コンクリート水槽にそれぞれ雌雄50尾ずつを収容し, 濾過海水による流水式で飼育し産卵数を調べた。産卵が認められた期間は5月6日から7月9日までの65日間で46回の産卵を確認することができた。産卵数は日によって大きく変動したが, 5月下旬から6月初旬および7月初旬の水温22℃前後のときに産卵盛期がみられた。次に期間中に水槽内で自然産卵された卵を用い, 水温21℃における時間の経過に伴う発生段階の観察を行った。卵は産卵後50分で2細胞期に達し, その後は5～20分毎に分裂を繰り返し, 2時間後には桑実期に, 6時間50分後には胞胚期に達し, 約39時間40分後から孵化が始まった。また, 水槽内で自然産卵された卵より得られた孵化仔魚を用い, 孵化から日齢30日までの成長について調べた。孵化仔魚の平均全長は3.56±0.08mmであったが, 孵化後30日間で96.02±4.89mmに成長した。
  • W Sakamoto; K Okamoto; T Uehabu; K Kato; O Murata
    NIPPON SUISAN GAKKAISHI 71 1 80 - 82 2005年01月 [査読有り]
  • K Kato; K Ishimaru; Y Sawada; J Mutsuro; S Miyashita; O Murata; H Kumai
    FISHERIES SCIENCE 70 6 1061 - 1069 2004年12月 
    A histological examination was made of the ontogenetic development of the digestive and immune systems of the larval and juvenile kelp grouper Epinephelus bruneus reared in the laboratory The liver, gall bladder, pancreas and the demarcating region between the intestines and rectum were formed within 3 days post-hatch (dph). During the preflexion phase (within 16 dph), revolution of the intestine concluded, and pharyngeal teeth and the mucous cells of the esophagus were differentiated. In the transitional period to the juvenile stage (25 dph), the blind sac of the stomach, gastric glands and pyloric caeca began to form. From the viewpoint of the differentiation phase of the adult-type digestive system, the kelp grouper is similar to Heterosomata, hitherto reported. The primordial thymus, kidney and spleen were present at 12, 1 and 6 dph, and the small lymphocytes in these lymphoid organs appeared at 21, 30 and 33 dph, respectively The developmental sequence of the lymphoid organs and the appearance ages of the lymphoid organs and small lymphocytes in the lymphoid organs in the kelp grouper are similar to those of other marine fish previously reported, except for the Pacific bluefin tuna Thunnus orientalis.
  • 魚類におけるクローン作出技術とその利用
    熊井 英水; 家戸 敬太郎; 村田 修
    Bio Industry Bio Industry 2004 21 7 - 17 2004年
  • K Kato; S Miyashita; O Murata; H Kumai
    FISH PHYSIOLOGY AND BIOCHEMISTRY 28 1-4 155 - 156 2003年 
    The gonadal sex differentiation in red sea bream, Pagrus major, which is one of the most important species for aquaculture in Japan, was revealed histologically. The suitable conditions for induction of all-male groups in the fish were investigated, and functional males were induced by the conditions of oral administration of 17alpha-methyltestosterone. The sex determination of this fish was also discussed.
  • M Watts; K Kato; BL Munday; CM Burke
    AQUACULTURE RESEARCH 34 1 13 - 21 2003年01月 
    Serial sections, prepared from 0.5 to 30 days post-hatch (dph) larval and juvenile Thunnus orientalis (Temminck & Schlegel 1844), were stained with haematoxylin and eosin and examined by light microscopy for immune organ development. The early kidney was present at 0.5 dph, undifferentiated stem cells began to appear at 2 dph, and by 7 dph occasional small lymphocytes were present. The thymus was first obvious at 5 dph, located above the fourth branchial arch, small lymphocytes appeared at 7 dph, and by 15 dph an outer thymocytic zone and an inner epithelioid zone were visible. The progenitor spleen was present at 2 dph, located close to the gut, and by 12 dph it consisted of a mass of sinusoids filled with red blood cells, and remained mainly erythroid throughout the period studied. These results suggest that development of immune organs in this species is precocious relative to other marine teleosts.
  • K Kato; S Miyashita; O Murata; H Kumai
    FISH PHYSIOLOGY AND BIOCHEMISTRY 28 1-4 155 - 156 2003年 
    The gonadal sex differentiation in red sea bream, Pagrus major, which is one of the most important species for aquaculture in Japan, was revealed histologically. The suitable conditions for induction of all-male groups in the fish were investigated, and functional males were induced by the conditions of oral administration of 17alpha-methyltestosterone. The sex determination of this fish was also discussed.
  • K Kato; R Hayashi; D Yuasa; S Yamamoto; S Miyashita; O Murata; H Kumai
    AQUACULTURE 207 1-2 19 - 27 2002年04月 
    Red sea bream, Pagrus major, is one of the most important fish cultured in Japan. Two clones of red sea bream were produced, Eggs from a mitotic gynogenetic diploid (mitotic-G2N) red sea bream were inseminated either with sperm from a mitotic-G2N male to produce a heterozygous clone (hetero-clone), or with UV-irradiated sperm of Japanese parrot fish (Oplegnathus fasciatus) and the second meiotic division suppressed by cold shock to produce a homozygous clone (homo-clone). Normal diploids were also produced from one male and female as a control. The clonal status of the Fish was confirmed by multilocus DNA Fingerprinting. The fingerprinting patterns differed between individuals within the normal diploids. However, there was no variation between individuals within hetero- or homo-clones. The patterns of the homo-clones and the mother were identical, and all the bands of homo-clones were also observed in hetero-clones. Thus, the clonal status of homo- and hetero-clones was confirmed and the production of clones from the broodstock of mitotic-G2N was achieved. The hatching rates, survival rates and growth of the hetero- and homo-clones were recorded for a brief comparison with results of diploid controls. (C) 2002 Elsevier Science B.V. All rights reserved.
  • K Kato; O Murata; S Yamamoto; S Miyashita; H Kumai
    JOURNAL OF APPLIED ICHTHYOLOGY 17 3 97 - 103 2001年06月 
    Two types of gynogenetic diploids were artificially induced in the red sea bream (Pagrus major Temminck et Schlegel), either by suppressing the first cell cleavage (mitotic-G2N) or by retaining the second polar body (meiotic-G2N). The eggs of red sea bream were inseminated with UV-irradiated (3000 erg mm(-2)) sperm of Japanese parrot fish (Oplegnathus fasciatus Temminck et Schlegel), and hydrostatic pressure shock of 700 kg cm(-2) for 5.5 min at 46 min after insemination (naitotic-G2N) and cold shock of 1 degreesC for 30 min at 3 min after insemination (meiotic-G2N) were applied to the eggs, sequentially, The total hatching rate and hatching rate of normal larvae of the normal diploid, meiotic-G2N and mitotic-G2N were 86.5 and 94.9%, 38.1 and 45.8%, and 12.8 and 35.0%, respectively. The induction of mitotic-G2N was confirmed by isozyme marker analysis. The standard deviations, variances and coefficients of variation of the body weight, standard length and body depth in 91-day-old juveniles were always large in mitotic-G2N, small in normal-2N and intermediate in meiotic-G2N. The variances in the number of pectoral fin rays and caudal fin rays of mitotic-G2N were significantly higher than those of normal-2N. The incidences of deformities were highest in the mitotic-G2N group. The survival rates and growth performance of the meiotic- and mitotic-G2N were significantly lower than those of normal-2N. Both G2N survived for 3 years to the adult stage.
  • 家戸 敬太郎; 林 律子; 糟谷 享; 山本 眞司; 村田 修; 熊井 英水
    水産増殖 49 3 339 - 345 日本水産増殖学会 2001年 
    マダイ,Pagrus majorにおける全雄群誘導に有効な17α-メチルテストステロン(MT)の経口投与量および投与時期について,雌性発生二倍体または雌と雌性発生二倍体雄との交配により得た魚を用いて調べた.281日齢の雌性発生二倍体マダイにMTを0.01-1.0mgMT/kg BW/dayの濃度で16週間経口投与した結果,MT投与の翌年の産卵期にはいずれの濃度区においても100%機能的な雄が得られた。55,141および893日齢の魚にMT(0.1mg/kg BW/day)処理を16週間行った結果,雄が誘導され,すべてのMT処理魚の生殖腺に精巣組織が認められた。141および893日齢より処理した群では機能的な精子が得られたものの,55日齢からの処理群では精子を得ることはできなかった。
  • Y Sawada; K Kato; T Okada; M Kurata; Y Mukai; S Miyashita; O Murata; H Kumai
    ICHTHYOLOGICAL RESEARCH 46 3 245 - 257 1999年08月 
    The growth and morphological development of larval and juvenile Epinephelus bruneus were examined in a hatchery-reared series. Average body length (BL) of newly-hatched larvae was 1.99 mm, the larvae growing to an average of 3.96 mm by day 10, 6.97 mm by day 20, 12.8 mm by day 30, 22.1 mm by day 40 and 24.7 mm by day 45 after hatching. Newly-hatched larvae had many mucous cells in the entire body epidermis. By about 4 mm BL, the larvae had developed pigment patterns peculiar to epinepheline fishes, including melanophores on the dorsal part of the gut, on the tips of the second dorsal and pelvic fin spines, and in a cluster on the ventral surface of the tail. Spinelets on the second dorsal and pelvic fin spines, the preopercular angle spine and the supraocular spine, had started to develop by about 6 mm BL. The notochord tip was in the process of flexion in larvae of 6-8 mm BL, by which time major spines, pigments and jaw teeth had started to appear. Fin ray counts had attained the adult complement at 10 mm BL. After larvae reached 17 mm BL, elements of juvenile coloration in the form of more or less densely-pigmented patches started to appear on the body. Squamation started at 20 mm BL. Major head spines had disappeared or became relatively smaller and lost their serrations by 20-25 mm BL.
  • 家戸 敬太郎; 林 律子; 石谷 大; 山本 眞司; 宮下 盛; 村田 修; 熊井 英水
    水産増殖 47 1 29 - 34 日本水産増殖学会 1999年 
    天然群に比べ成長が早い選抜育種マダイにおける飼育条件下での性分化過程について組織学的に検討した。その結果, 孵化後3および4ヶ月目において全個体の生殖腺に卵巣腔が観察された。孵化後7ヶ月目には40尾中34尾に卵母細胞を持つ個体がみられた。孵化後8ヶ月目以降の当歳魚において, 生殖腺中に卵母細胞と精母細胞が両方存在する雌雄同体 (以下, ♀♂と略記) が約半数の個体に出現した。1歳魚の6月 (孵化後約1年4ヶ月) までの生殖腺は, 卵巣または♀♂のいずれかで, 1歳魚の9月以降および2歳魚の生殖腺では卵巣および♀♂のほかに精巣も確認された。3歳魚には雌雄同体はみられなかった。以上の結果から, 選抜育種マダイの性分化過程としては, 稚魚期には全個体の生殖腺が卵巣へと分化し, 半数の個体はそのまま雌になるが, 残りの半数の個体では孵化後8ヶ月目頃から精巣が発達し始め, 1～2歳魚にかけて完全な雄に分化すると考えられた。
  • 宮下 盛; 家戸 敬太郎; 澤田 好史; 村田 修; 石谷 大; 清水 清和; 山本 眞司; 熊井 英水
    水産増殖 46 1 111 - 120 日本水産増殖学会 1998年 
    クロマグロの種苗生産に関する基礎的知見を得ることを目的として, 人工孵化クロマグロの孵化後の成長に伴う消化系の発達および消化酵素活性について調べ, 次の結果を得た。孵化後36時間目までに, 肝臓, 胆嚢および膵臓が形成され, トリプシン様酵素およびアミラーゼ活性は摂餌開始後成長に伴い増加した。Preflexion期 (孵化後10日まで) に腸の回転が完了し, 咽頭歯および食道の粘液細胞が分化した。Flexion期 (孵化後11～17日) に機能的な顎歯がみられ, 胃盲嚢, 胃腺および幽門垂が形成され始めた。ペプシン様酵素活性は胃腺の形成に伴って増加し, Postflexion期から稚魚への移行期 (孵化後17～25日) にかけて胃の機能および幽門垂が著しく発達した。標準体長に対する肛門前長の比は孵化後11日目までは約40%で一定であったが, 26日目にかけて約65%まで増加し, 26日目から30日目まではほとんど変化しなかった。
    以上の結果から, クロマグロの消化系は孵化後11日目まで (Preflexion期) は主として質的に発達し, それ以降26日目まで (Flexion期からPostflexion期) は量的な発達が伴うことが示唆され, このような量的および質的な消化系の発達が稚魚期の急速な成長に貢献するものと推察した。
  • 家戸 敬太郎; 村田 修; 中新井 隆; 那須 敏朗; 宮下 盛; 熊井 英水
    水産増殖 46 2 203 - 212 水産増殖談話会 1998年
  • O Murata; S Miyashita; K Izumi; S Maeda; K Kato; H Kumai
    FISHERIES SCIENCE 62 6 845 - 849 1996年12月 
    We attempted to improve the breed of red sea bream Pagrus major by means of selective breeding in order to establish red sea bream seedling for aquaculture capable of growing more quickly than natural red sea bream. In about 1964, natural young fish were reared into broodstock and, among young fish obtained from these broodstock, those growing quickly were selected and reared into broodstock. This selective breeding has been repeatedly carried out for more than 25 years. The following results were obtained. (1) As the selective breeding was repeated, the body weight of broodstock aged 4 years showed an increase. (2) The selected red sea bream seedling grew at an obviously elevated rate as the selective breeding was repeated. Namely, the time (days) required for attaining a commercially available fish size (about 1 kg) was shortened. (3) The average realized heritability, which was determined by the average body weight of 4-year-old broodstock and body weight of 4-year-old fish in the growth curve of each generation, was 0.33 +/- 0.28.
  • K KATO; Y ISHIBASHI; O MURATA; T NASU; S IKEDA; H KUMAI
    FISHERIES SCIENCE 60 5 589 - 596 1994年10月 
    The qualitative requirements and deficiency signs of water-soluble vitamins were studied in tiger puffers Takifugu rubripes having mean body weight of 2.9 g. The qualitative requirements of tiger puffer for water-soluble vitamins indicate that the requirement of this species for vitamin B6 is lower than that of other fish species such as red sea bream, yellowtail, and Japanese parrot fish, while that for vitamins related to lipid metabolism, such as choline, nicotinic acid, pantothenic acid, biotin and inositol, is comparatively high.
  • 石橋 泰典; 家戸 敬太郎; 池田 静徳; 村田 修; 那須 敏朗; 熊井 英水
    水産増殖 42 2 279 - 285 水産増殖談話会 1994年06月 [査読有り]
  • Y ISHIBASHI; K KATO; S IKEDA; O MURATA; T NASU; H KUMAI
    NIPPON SUISAN GAKKAISHI 58 11 2147 - 2152 1992年11月 
    Control and stressed groups of juvenile Japanese parrot fish Oplegnathus fasciatus were fed diets (moist pellet) supplemented with 0, 75, and 300 mg of ascorbic acid (AsA) per 100 g. Fish in the stressed group were intermittently exposed to decreasing water oxygen levels every 3 or 4 days for 16 weeks. In the fish given a diet containing no AsA supplement, AsA-deficiency symptoms were manifested earlier, and to a greater extent, in the stressed fish than in the non-stressed ones. Similarly, the growth of stressed fish fed on a diet supplemented with 75 mg AsA per 100 g was inferior to the growth of the control group, and in the stressed fish there was a reduction in AsA levels in the plasma, kidneys, and gills. On the other hand, fish fed on a diet supplemented with 300 mg of AsA per 100 g were barely affected by the stressor. These results indicate that, in Japanese parrot fish under these experimental conditions, exposure to intermittent hypoxic stress not only induced AsA-deficiency disease early, but also increased the AsA requirement. It was also shown that high doses of AsA increased the ability of these fish to resist the stressor.
  • Y ISHIBASHI; K KATO; S IKEDA; O MURATA; T NASU; H KUMAI
    NIPPON SUISAN GAKKAISHI 58 8 1555 - 1555 1992年08月

書籍

  • 家戸, 敬太郎 朝倉書店 2021年02月 ISBN: 9784254485059 viii, 187p, 図版 [4] p
  • 間野, 伸宏; 鈴木, 伸洋 成山堂書店 2020年05月 ISBN: 9784425831210 xx, 285p, 図版 [8] p
  • 植田, 充美 シーエムシー出版 2020年04月 ISBN: 9784781314969 v, 246p
  • 近畿大学水産研究所 日刊工業新聞社 2019年02月 ISBN: 9784526079443 159p
  • Advances in Tuna Aquaculture from Hatchery to Market
    Alejandro Buentello; Manabu Seoka; Keitaro Kato; Gavin J. Partridge (担当:共著範囲:Tuna Farming in Japan and Mexico)Elsevier 2015年12月
  • メジナ 釣る？ 科学する？
    家戸敬太郎; 熊井英水 (担当:共著範囲:メジナとイシダイの雑種－幻になった”メジナ”－)恒星社厚生閣 2011年07月
  • 食のバイオ計測の最前線―機能解析と安全・安心の計測を目指して―
    家戸 敬太郎 (担当:共著範囲:完全養殖クロマグロのブランド化とトレーサビリティ手法)シーエムシー出版 2011年05月
  • 水産物の色素－嗜好性と機能性
    足立亨介; 家戸敬太郎 (担当:共著範囲:養殖マダイのメラニン－その誘発因子と化学的定量)恒星社厚生閣 2008年03月
  • 水産増養殖システム4 アトラス
    恒星社厚生閣 2007年
  • 水産増養殖システム1 海水魚
    恒星社厚生閣 2005年
  • 養殖・畜養システムと水管理
    恒星社厚生閣 2004年
  • 水の特性と新しい利用技術 農業・食品・医療分野への応用
    エヌ・ティー・エス 2004年
  • Aquatic Genomics. Steps toward a great future
    Springer-Verlag 2003年
  • 最新海産魚の養殖
    湊文社 2000年
  • Advances in Marine Aquaculture
    2000年

講演・口頭発表等

  • マアナゴ天然魚と養殖魚との美味しさの比較  [通常講演]
    家戸敬太郎; 尾賀光輔; 竹内芳恵; 森 喜代美; 山田伸一; 升間主計
    平成29年度日本水産学会春季大会 2017年03月 口頭発表（一般）
  • Increment of Skeletal Muscle Mass by CRISPR/Cas9 Genome Editing System in Red Sea Bream (Pagrus major)  [通常講演]
    家戸 敬太郎
    Aquaculture Europe 2016 2016年09月 ポスター発表
  • ゲノム編集による海水養殖魚の品種改良とその産業化に向けた課題  [通常講演]
    家戸敬太郎; 鷲尾洋平; 安齋 賢; 豊田 敦; 吉浦康寿; 黒柳美和; 片山貴士; 今井 正; 瀬水研; 岸本謙太; 村上 悠; 木下政人
    平成28年度日本水産学会秋季大会 2016年09月 口頭発表（一般）
  • アナゴ・サクラマス  [通常講演]
    家戸 敬太郎
    平成28年度日本水産学会秋季大会水産増殖懇話会第2回講演会「魚類養殖の新たしいビジネスモデル」 2016年09月 シンポジウム・ワークショップパネル（指名）
  • 海水魚の完全養殖とその産業化  [招待講演]
    家戸 敬太郎
    生物工学若手研究者の集い 夏のセミナー2014 2014年07月 口頭発表（招待・特別）
  • 田辺湾養殖漁場の底泥に蓄積する有機物量の増減パターン  [通常講演]
    中瀬 玄徳; 江口 充; 家戸 敬太郎; 宮下 盛; 谷口 亮人; 諏訪 剛
    平成24年度日本水産学会春季大会 2012年03月 平成24年度日本水産学会春季大会
  • クロマグロ人工種苗生産の産業化  [通常講演]
    岡田 貴彦; 倉田 道雄; 高岡 治; 向井 良夫; 田村 利博; 石橋 泰典; 宮下 盛; 澤田 好史; 滝井 健二; 家戸 敬太郎; 村田 修; 熊井 英水; 半澤 淳也; 若杉 金市郎
    日本水産学会 平成22年度日本水産学会 春季大会 2010年03月 東京 日本水産学会 平成22年度日本水産学会 春季大会
  • マダイα-アクチン遺伝子3種の発現解析およびプロモーター活性  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 木下 政人
    2006年04月
  • 海産魚類の初期胚操作のための技法開発  [通常講演]
    小林 徹; 大谷 哲; 家戸 敬太郎; 宮下 盛
    日本水産学会 2006年04月 平成18年度日本水産学会大会（高知大，高知市） 日本水産学会
  • トラフグ種苗生産へのフグ毒（TTX)利用の影響  [通常講演]
    熊井 英水; 村田 修; 山本 眞司; 家戸 敬太郎
    2006年03月
  • 低水温飼育によって誘発されるマダイ稚魚の変色  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 伊藤 祥輔; 若松; 石丸 克也
    2006年03月
  • 海殖魚プロラクチン、ソマトラクチンの概日発見とその相関  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 石丸 克也
    2006年03月
  • マダイ胚cDNAデーターベースの構築とcDNAマイクロアレイの作成  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 川路 英哉; 田丸 浩
    2005年12月
  • The Necessity of Disease Management in the Seedling Production of the Marine Finfish  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修
    2005年10月
  • Annottions and expression profiles of 9,408 clones from embryonic cDNA libraries of red sea bream,Pagrus major  [通常講演]
    熊井 英水; 家戸 敬太郎; 澤田 好史; 村田 修; 秋山 真一
    2005年06月
  • Expression profile of GH and IGF-I for Pacific biuefin tuna at early phase.-Comparative analyis for the species with variant growth rate  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 岡田 貴彦
    2005年06月
  • Development of transgenic technology for red sea bream,  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 高木 優喜; 秋山 真一; 田丸 浩
    2005年06月
  • マダイ体表のユーメラニン,フェオメラニンの定量  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 石丸 克也; 米島 久司; 若松 一雅; 伊藤; 平田 孝
    2005年04月
  • マダイ胚のDNAライブラリー構築と解析  [通常講演]
    熊井 英水; 家戸 敬太郎; 澤田 好史; 村田 修; 秋山 真一; 川路 英哉
    2005年04月
  • マアナゴのレプトケファルスからの飼育  [通常講演]
    熊井 英水; 村田 修; 家戸 敬太郎; 宮下 盛; 米島 久司
    2005年04月
  • クロマグロ稚魚の成長ホルモン概日リズムに関する研究  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修
    2005年04月
  • 養成クロマグロの産卵環境と４才魚の生殖線発達  [通常講演]
    熊井 英水; 瀬岡 学; 坂本 亘; 家戸 敬太郎; 村田 修; 向井 良夫; 八木 洋樹
    2005年04月
  • マダイにおける初期発生過程  [通常講演]
    長谷川 徹; 大谷 哲; 大原 学; 上野 紘一; 家戸 敬太郎; 小林 徹
    日本水産学会 2005年04月 平成17年度日本水産学会大会(東京海洋大，港区） 日本水産学会
  • 串本および奄美大島におけるクロマグロの産卵  [通常講演]
    熊井 英水; 瀬岡 学; 家戸 敬太郎; 村田 修; 宮下 盛; 坂本 亘; 岡田 貴彦; 八木
    2004年04月
  • 奄美大島におけるクロマグロ３才魚の生殖腺の発達  [通常講演]
    熊井 英水; 家戸 敬太郎; 瀬岡 学; 村田 修; 宮下 盛; 坂本 亘; 向井 良夫
    2004年04月
  • 海産魚の遺伝子導入用発現ベクターの開発  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 田丸 浩
    2003年12月
  • 海産魚の遺伝子導入発現ベクターの開発  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 田丸 浩
    2003年11月
  • クエの卵子化および初期飼育に及ぼす水温の影響  [通常講演]
    熊井 英水; 家戸 敬太郎; 山田 伸一; 村田 修
    2003年10月
  • Breeding in red sea bream,Pagrus major in Japan Inteanational Marine Biotechnology Conference 2003  [通常講演]
    熊井 英水; 家戸 敬太郎; 宮下 盛; 村田 修
    2003年09月
  • Gonadal sex differentation and sex control in red sea bream,Pagrus major 7th International Symposium on Reproductive physiology of Fish  [通常講演]
    熊井 英水; 家戸 敬太郎; 宮下 盛; 村田 修
    2003年05月
  • 雌性発生二倍体マダイおよびそれらの子孫性比  [通常講演]
    熊井 英水; 家戸 敬太郎; 村田 修; 宮下 盛
    2002年11月
  • エストラジオール経口投与によるマダイの雌化誘導法の検討  [通常講演]
    熊井 英水; 村田 修; 宮下 盛; 家戸 敬太郎
    2002年03月

作品等

  • 食資源動物の科学
    1997年 -2001年
  • 海水養殖魚におけるトランスジェニック技術の開発
    2000年
  • 染色体操作によるクローンマダイの作出
    1998年
  • Production of cloned red sea bream by chromosme manipulation
    1998年
  • マダイの性統御に関する研究
    1997年
  • 選抜育種マダイの性分化過程
    1997年
  • Studies on the Sex Control in Red Sea Bream
    1997年
  • Gonadal sex differentiation of a selected strain of red sea bream
    1997年
  • 選択系と非選択系マダイとの成長,飼料効率などの比較
    1996年
  • Comparison of growth and feed efficiency between selection strain and non-selection strain in red sea bream
    1996年
  • 雌性発生二倍体マダイの作出
    1995年
  • 人工孵化クエ仔稚魚の成長に伴う消化系の発達
    1995年
  • Production of Gynogenetic Diploids of Red Sea Bream
    1995年
  • Development of digestive system and digestive system of larvae and juvenile kelp grouper
    1995年
  • 人工孵化クロマグロ仔稚魚の消化系の発達と消化酵素活性
    1994年
  • Development of digestive system and digestive enzyme activities of larvae and juvenile bluefin tuna
    1994年
  • Population genetic analysis of red sea bream seedling produced by selective breeding
    1994年
  • Suitable Protein and Lipid Levels in Diet-for Fingerlings of Goldstriped Amberjack
    1993年
  • Suitable Protein and Lipid Levels in Diet for Fingerlings of Purplish Amberjack
    1993年
  • Comparison of growth and chemical composition between diploid and triploid in Japanese parrot fish
    1989年 -1992年
  • Qualitative Requirements of the Tiger Puffer for Water-Soluble Vitamins
    1992年

MISC

受賞

  • 2022年03月 公益社団法人日本水産学会 令和3年度水産学進歩賞
     マダイの品種改良に関する研究 japan_society

共同研究・競争的資金等の研究課題

  • 日本学術振興会：科学研究費助成事業
    研究期間 : 2017年04月 -2020年03月 
    代表者 : 木下 政人; 堀部 智久; 鷲尾 洋平; 家戸 敬太郎; 有馬 祐介
     
    魚類や甲殻類へのゲノム編集を行うには、通常、受精卵へのマイクロインジェクション法(MI)を用いる。しかしながら、魚類、甲殻類ではモデル生物として確立されている種は少なく、モデル生物以外では計画的に受精卵を得ることが難しい。そこで受精卵へのMIを用いないゲノム編集方法の開発に取り組んだ。 多くの魚類では肝臓で作られたビテロゲニンが卵内に蓄積される。このシステムを用いて肝臓で発現させたCas9タンパク質を卵に蓄積させ、ゲノム編集を完成させることを考えた。 ビテロゲニンの卵への輸送シグナルと緑色蛍光タンパク質を融合させると、肝臓から卵黄への輸送は成功したが、卵の細胞質への輸送は成功しなかった。
  • 日本学術振興会：科学研究費助成事業
    研究期間 : 2014年04月 -2017年03月 
    代表者 : 木下 政人; 豊田 敦; 家戸 敬太郎; 吉浦 康寿; 岸本 謙太; 村上 悠; 片山 貴士; 鷲尾 洋平
     
    養殖魚の育種はほとんど行われていないのが現状である。伝統的な選抜育種法による育種は、長期間を要するという欠点があった。そこで、ゲノム編集法の一つであるCRISPR/Cas9を用いて、マダイとトラフグにおいてミオスタチン遺伝子を破壊することで筋肉増量品種作製を試みた。ミオスタチン遺伝子のエキソン１内の配列をターゲットを設定し、single guideRNAおよび Cas9 RNA を人工授精した１細胞期の受精卵にマイクロインジェクション法により導入した。その結果、いずれの魚種においても高効率でミオスタチン遺伝子破壊に成功し、筋肉量を増加した個体の作製に成功した。
  • 日本学術振興会：科学研究費助成事業
    研究期間 : 2009年04月 -2014年03月 
    代表者 : 江口 充; 谷口 亮人; 家戸 敬太郎; 中川 至純
     
    種苗生産では経験的に微細藻類を飼育水に添加し、仔稚魚減耗の低減化を図る。これを海外ではGreen Water（水作り）と呼ぶ。本研究では、そのメカニズムを微生物生態学的側面から科学的に検証した。その結果、活発に増殖する微細藻類の培養液中に善玉菌（Roseobacterグループ）が質的（多種類）にも量的にも多く存在し、微細藻類と善玉菌が協働して、悪玉菌（例えばVibrio属の魚病細菌）の増殖を特異的に抑制し、時には死滅させることが明らかになった。
  • 日本学術振興会：科学研究費助成事業
    研究期間 : 2007年 -2009年 
    代表者 : 家戸 敬太郎; 豊原 治彦; 木下 政人
     
    前年度の研究で,transposase認識配列を付加した発現ベクターをマダイ受精卵に導入することで,transposaseのmRNAの共インジェクションの有無にかかわらず12.4～14.7%の個体の鰭からGFP遺伝子が検出され,共インジェクションした場合には斃死個体から高率でGFP遺伝子が検出された。このようにメダカのtransposase認識配列をマダイが認識して転移する能力が示唆されたが,マダイ由来の転移があることからtransposaseシステムは安定的なトランスジェニック系統作出の技術として問題があることが考えられた。そこで本年度は18塩基の配列を認識可能なmeganucreaseの利用について検討した。 骨格筋で強く発現するα-アクチンプロモーターに緑色蛍光タンパク質(GFP)遺伝子を連結したDNA断片の両端にmeganucrease I-SceIの認識配列を付加したプラスミドベクターを作成した。2009年12月に秋季から冬季にかけて産卵する香港系統のマダイから採卵し,上記発現ベクターおよびI-SceIの共インジェクションを試みたが,卵質が悪く発生しなかった。そこで,急遽マダイ4歳魚を陸上水槽に収容して蛍光灯による長日処理および加温によって成熟を誘導したところ,1月中旬から産卵を開始した。産卵が安定するのを待って,2月11日にマダイ受精卵へのマイクロインジェクションを再度行った。上記の発現ベクター100ng/μlとI-SceIを3U/μlおよび1U/μlの濃度で共インジェクションする試験区と,発現ベクターのみをインジェクションする対照区を設定し,各試験区とも1,000粒以上の卵にマイクロインジェクションした。 その結果,3U区で230尾,1U区で315尾,対照区で309尾の孵化仔魚が得られ,3U区のみに骨格筋にGFPを発現する個体が認められた。GFP発現観察後はそれらの仔魚を飼育した。
  • 腸内細菌によるマダイのエドワジェラ症予防
    研究期間 : 2008年 
    腸内細菌叢をコントロールすることでマダイのエドワジェラ症を予防する技術を開発する
  • 日長調節による海水養殖魚の成熟抑制に関する研究
    研究期間 : 2008年 
    日長調節によってブリやマダイなどの海水養殖魚の成熟を抑制し，養殖生産効率の向上を図る
  • グロマグロの成熟・産卵に関する研究
    科学研究費補助金
    研究期間 : 2002年 -2006年
  • Study on reproduction of bluefin tuna
    Grant-in-Aid for Scientific Research
    研究期間 : 2002年 -2006年
  • 日本学術振興会：科学研究費助成事業
    研究期間 : 2003年 -2005年 
    代表者 : 豊原 治彦; 木下 政人; 家戸 敬太郎
     
    マダイから自己消化の原因酵素MMPとその内因性インヒビターTIMP、及び3種類のαアクチン遺伝子をクローニングすることに成功した.αアクチン遺伝子については、2種類は骨格筋アクチン(骨格筋1型と2型)を,1種類は心筋アクチン遺伝子(心筋型)であると推測された.いずれの遺伝子も8個のエクソンから構成されており,上流域にE BoxとCArG Boxを有していたが,これらのモチーフの分布パターンに大きな違いが認められた. これら3種類のαアクチン遺伝子の発現調節領域を利用したマダイ専用の発現ベクターを構築した.これらのベクターは,エクソンIIからVIIの領域をGFPと入れ換えたものであり,これらの調節領域のGFP発現誘導活性を比較することで調節領域の発現誘導活性を比較することが可能となった.また、マダイ受精卵へのマイクロマダイ受精卵への導入2日後の生残率は,骨格筋1型が35.7%,骨格筋2型が16.6%,心筋型が30.8%であった.孵化後1日と10日後の仔魚ならびに4ヵ月後の稚魚及び成魚の骨格筋と心筋における発現を調べた結果,いずれの遺伝子も仔魚期から発現していることが明らかとなった.しかし,骨格筋1型が稚魚と成魚のいずれにおいても骨格筋と心筋の両方において強く発現されていたのに対し,骨格筋2型は稚魚と成魚では骨格筋においてのみ発現が確認された.興味深いことに心筋型は稚魚期には心筋でのみ発現が認められたが,成魚では心筋と骨格筋のいずれにおいても発現が確認された.上記の発現ベクターを導入したF_0を用いてGFPの発現を視覚的に検討した結果,いずれのベクターも筋肉細胞特異的な発現誘導活性を有することが示されたが,心筋型遺伝子を用いたベクターではGFPが特に限定的な部位で発現していることが認められた。 これらの結果を元に、発現ベクターを構築し、現在、マダイTIMP遺伝子を導入したF0を200尾飼育している。これらの個体は来年には成熟することから、今後、交配によりTIMPを過剰発現させたトランスジェニックマダイの系統を作出する予定である。
  • クロマグロの初期発育と種苗生産に関する研究
  • 海水養殖魚の遺伝・育種に関する研究
  • Study on early development and seedling production of bluefin tuna, ┣DBThunnus thynnus(/)-┫DB
  • Study on genetics and breeding of cultured marinfish

委員歴

  • 2015年04月 - 現在   日本水産増殖学会   評議員
  • 2013年04月 - 現在   日本水産学会   近畿支部幹事
  • 2018年04月 - 2020年03月   日本水産学会   理事
  • 2009年04月 - 2015年03月   日本水産学会   - 編集委員

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