組織学的観察に基づく筑後川産両側回遊型アユの成熟・産卵様式〔両側回遊型アユの成熟・産卵に関する研究-1-〕

概要

論文の詳細を見る
The process of oocyte maturation and the seasonal changes of ovarian development were observed with the amphidromous type Ayu captured at Chikugo River, Fukuoka Prefecture, Japan. In the oocytes of the fish, three kinds of the vitelline elements, i. e. yolk vesicles, yolk globules and oil droplets appeared in this order. In the mature eggs, yolk globules never formed a massed yolk in spite of increasing in size. Accumulation of yolk rapidly proceeded and was completed in about three weeks. The oocytes showed the development of asynchronous type and the mature ovaries contained groups of oocytes in various maturation stages at the same time. Therefore the ovarian maturity of the fish is adequately represented by the histological maturation stage of the oocytes that have the modal value of diameter in the first batch (the most advanced group of oocytes). After the first batch was ovulated, the second batch developed up to secondary yolk globule stage at most. But long without ovulation of the second batch.
日本水産學會の論文