Associate Professor
Faculty Department of Fisheries / Graduate School of Agriculture

Education and Career


  • 1994/04 - 1998/03 , Nagasaki University, Faculty of Fisheries,
  • 1998/04 - 2000/03 , Nagasaki University, 水産学研究科,
  • 2001/04 - 2004/03 , 北海道大学大学院, 理学研究科,

Academic & Professional Experience

  • Nov. 2022 - Feb. 2023 , University of Otago Department of Zoology (近畿大学 在外研究)

Research Activities

Research Interests

生殖, 性転換, 水産, 魚類

Published Papers

  1. Diversity and evolution of serotonergic cells in taste buds of elasmobranchs and ancestral actinopterygian fish
    Takanori Ikenaga; Tastufumi Nakamura; Tatsushi Tajiri; Minaki Tsuji; Dai-ichiro Kato; Toshinao Ineno; Yasuhisa Kobayashi; Naoaki Tsutsui; Sadao Kiyohara
    Cell and Tissue Research  394  (3)  , 431-439, 18, Oct. 2023 
  2. Induction of precocious sex reversal in aquaculture: effects of methyltestosterone treatment on gonadal sex of yearling longtooth grouper (Epinephelus bruneus)
    Kobayashi, Y; Keyamura, O; Lokman, M. P; Chuda, H
    International Journal of Aquatic Biology  11  (6)  , 571-576, 2023  , Refereed
  3. Gamete-exporting organs of vertebrates: dazed and confused.
    Akira Kanamori; Yasuhisa Kobayashi
    Frontiers in cell and developmental biology  11  , 1328024-1328024, 2023 


Books etc

  1. 魚類の性決定・性分化・性転換 : これまでとこれから = Sex determination, sex differentiation and sex change in fishes-past, present and future , 菊池, 潔; 井尻, 成保; 北野, 健; 日本水産学会 , 恒星社厚生閣 , Mar. 2021
  2. 遺伝子から解き明かす魚の不思議な世界 : 水面下で起きた4億年の進化物語 , 神田, 真司 , 一色出版,悠書館 (発売) , Aug. 2019
  3. Sex Differentiation, Sex Change, and Sex Control in Groupers , Masaru Nakamura; Yasuhisa Kobayashi , 735-750 , 735-750 , John Wiley & Sons , Jan. 2019



  1. 霊長類ニホンザルにおけるGastrin-releasing peptide神経系の機能局在 , 高浪景子; 伊藤隆志; 越智拓海; 小林靖尚; 佐藤慧太; 上田康雅; 坂本竜哉; 坂本浩隆 , 日本解剖学会総会・全国学術集会講演プログラム・抄録集 , 123rd , 2018
  2. Spawning period and reliability of sexual distinction based on visual gonad observation of red spotted grouper Epinephelus akaara in the central Seto Inland Sea, Japan , Masayuki Yamamoto; Yasuhisa Kobayashi , Aquaculture Science , 65 , 2 , 165 , 169 , 2017
    Summary:Red spotted grouper Epinephelus akaara is one of the important commercial fish in the Seto Inland Sea. In order to continuously use the wild resources, basic biological data of grouper, especially spawning period and sex ratio, are required. In this study, we examined the maturation stages of gonads of grouper caught in eastern Hiuchi-nada, central Seto Inland Sea, in June, July, and November 2013, and August 2014, based on histological observation (histological method). Additionally, we identified the sex of individuals by macroscopic observation of gonads (morphological method) and compared the results of both the methods. Mature individuals were observed in both sexes between June and August, although immature females and intersexual individual were observed in June. Only immature individuals in both sexes were observed in November. Some immature individuals were considered to be of the incorrect sex by the morphological method in June and November, whereas all individuals were identified to be of the correct sex in July and August. Based on the results, the spawning period of red spotted grouper ranged from June to August, with the peak in July. Moreover, reliability of identification of sex by the morphological method was high in July and August.
  3. 関西の夏の味覚であるハモは、ウナギ目魚類の新たな実験モデルになるか? , 小林 靖尚 , 比較内分泌学 = Comparative endocrinology , 42 , 159 , 90 , 92 , Sep. 2016


Research Grants & Projects

  1. 日本学術振興会, 科学研究費助成事業 基盤研究(C), ハタ科魚類クエの早期性転換誘導:応用展開とその生理機構について , 近畿大学
  2. Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Histological observation of gonadal sex differentiation in the cartilaginous fish, the red stingray (Hemitrygon akajei). , Kindai University
  3. Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Molecular mechanisms of sex differentiation and sex-reversal in medaka complex, Oryzias sakaizumii, as a new model species for aquaculture , University of Shizuoka