Overripening of ovulated eggs in goldfish

Goldfish eggs retained in the ovarian cavity become overripe within 24 h after ovulation. Three stages of an overripening process could be identified. The overripe egg is characterized by increased translucency, movement of cytoplasm with cortical alveoli and unfused oil droplets to the animal pole, partial breakdown of the cortical alveoli, and finally the intermingling of these cell components with yolk granules in later stages. It is also larger than the newly ovulated egg and its chorion is thinner with surface modifications involving the recessing or disappearance of the pore plugs.