FN Archimer Export Format PT C TI Etude experimentale de la maturation ovocytaire chez Pecten maximus et Crassostrea gigas (Mollusca, Bivalvia) OT Experimental study of oocytic maturation in Pecten maximus and Crassostrea gigas (Mollusca, Bivalvia). BT AF WIDOWATI, L COCHARD, Jean-Claude DORANGE, G LE PENNEC, M AS 1:;2:;3:;4:; FF 1:;2:PDG-DOP-LER;3:;4:; SI BREST SE PDG-DOP-LER UR https://archimer.ifremer.fr/doc/1991/acte-1632.pdf LA French DT Proceedings paper DE ;Crassostrea gigas;Pecten maximus;Bivalvia;Marine molluscs;Animal reproductive organs;Larvae;Fecundity;Experimental research;Spawning;Sexual maturity AB To date, it has been impossible to fertilize the oocytes of ripe Pecten maximus obtained by gonad stripping as it is routinely done in hatchery with Crassostrea gigas . The events occurring between artificial induction of spawning and normal fertilization were studied experimentally in order to explain this difference. Fertilization and rearing trials were performed on oocytes obtained from the gonads of both species by scarification, by aspiration from genital ducts (of P. maximus only) and after spawning. Every batch of oocytes was fixed for histological study. Serial sections of the gonad of a fixed spawning P. maximus were made to reveal modifications of the nucleus of the oocytes during their expulsion. In P. maximus the stripped oocytes can be fertilized and are viable only when spawning is initiated. Histological sections show that germinal vesicle breakdown occurs at this very moment. The same was observed in C. gigas but it appears that in this species sperm can also induce the oocyte maturation of stripped oocytes. PY 1991 PD NOV CT Actes de colloques. Ifremer. Brest [ACTES COLLOQ. IFREMER.]. 1991 ID 1632 ER EF