クロダイの種首生産に関する基礎的研究 : Ⅰ. 生殖腺刺激ホルモン投与による成熟および 産卵の促進について

Fundamental studies on techniques of mass-production of fry of the black porgy, Mylio macrocephalus : I. On the spawning induced by injection of a preparation of mammalian gonadotropic hormones

Kasahara Shogoro

Hibiya Takashi

広島大学水畜産学部紀要

Journal of the Faculty of Fisheries and Animal Husbandry, Hiroshima University

　鹹水養池で粗放的に養殖されたクロダイ雌魚，生殖腺刺激ホルモンとしてシナホリンを注射した.
のち，雄魚とともに水槽に収容して，下記のような結果を得た.
1) 産卵期に入る前の未熟期から約1ヶ月聞にわたり， 4回の注射により全量62RUを投与した満4
年魚において良好な産卵結果が得られたほか，満3年魚においても産卵がみられた.
2) 産卵期における未完熟魚に１同(20RU) または2回(40RU) の注射により，満4年魚に産卵
個体が多くみられた.

Using the adults of 3 or 4 years of age of black porgy which were cultured extensively in the brackish-water fishponds, some trials were made in the artificial inducement of spawning of the fish. Female fish were mated with males in small concrete tanks after intramuscular injections of saline solution of "Synahorin" (mammalian gonadotropin preparation), and the results obtained were as follows.

1) Development of the ovaries of every semimature female recipient fish was evidently hastened by injections prior to the spawning season or early in that.

2) Then, two out of three females of 4 years of age successfully spawned after 62 RU in total dosage was respectively given by means of injecting in four doses during about one month, while partial spawning occurred in only one out of four females of 3 years with the above and additional injections.

3) In the spawning season, as the results of injections of respective dosage of 20 RU (once) or 40 RU (twice) into many females which were ripening but had not yet spawned, some of them mostly in females of 4 years of age could be induced to spawn.

Fishing industry. Fisheries [ 660 ]

jpn

広島大学水畜産学部

[ISSN] 0440-8756

[NCID] AN00213563