A histological and macroscopic study of ovarian development in the grey mullet, Liza carinata (Valenciennes 1836)

摘要

Developmental and maturational stages in the ovaries of Liza carinata (Valenciennes 1836) are described using microscopic and macroscopic techniques. Ten developmental stages are identified in the ovaries beginning with oogonia which proliferate through mitotic divisions, giving rise to perinucleolar oocytes. With the elaboration of yolk in the oocytes, the latter transform into vitellogenic oocytes. After the attainment of maximum size of the cells, nuclear polarization takes place, followed by prematuration of the oocytes and, finally, the release of the eggs from the follicle. Seven maturational stages in the ovary are recognized based on size, shape, texture and colour of the ovaries. The reproductive cycles begins after a long quiescent period from May through August, reaches a peak in October-November and ends with spawning in December-January.