台灣近海?嘉?魚之性轉變現象

Abstract

1．由生殖腺的組織觀察和性比與魚齡之關係，發現台灣基隆近海漁區鯛科嘉?魚有雙性現象，且屬原雌型。雌雄同體生殖腺為過渡期的生殖腺。 2. 性轉變是在2至6齡魚中進行的，其中以2齡最旺盛。性轉變之時間至少一年；有些可能持續二至三年。 3．在卵巢壁上常可發現一些增厚的地方，其中有被結締組識包圍的原始生殖細胞。這些細胞增殖形成睪丸，而取代萎縮和被吸收之卵巢。

1. Based on the histological observations of the gonads and on the sex ratio in the different age groups of red sea bream. It is concluded that the sparid fishes, Chrysophrys major, undergo sex rversal. They are protogynous. Ovatestis are transitory ones. 2. Sex reversal occures in 2-to 6- year old, and most frequently in 2- year-old fishes. The transformation of hermaphroditic gonads to the complete testis, takes at least one year and may last for 2 to 3 years. 3. Observation suggest that the primordial germ cells and the adjacent connective tissue found in the ovarian will are the precursors of the developing testis.