Cycle ovarien du merlu, Merluccius merluccius , poisson a ponte fractionnee.

The present work analyses and describes Merluccius merluccius ovarian cycle in the Bay of Biscay as an example of partial spawner. Three methods were employed: a macroscopic examination of about 10,000 ovaries -- a cytologic and histologic study -- an investigation of the size structure of the oocytes population of 63 ovaries. The author developed an original mathematical method for serial spawning demonstration. He demonstrates that hake is a partial spawner: a female usually rapidly spawns 4 or 5 times without ovaries rest. On this basis, he gives a new reference scale of the maturity stages of the ovarian cycle: after developing (II), ripe (III), running (IV), the partly spent ovary is named (II+); the repetitive sequence III-IV-II + characterize serial spawning. Then, the spent ovaries (V) go to recovering stage (VI), and resting stage (VII).