The rounded tip is in-serted in the genital opening, and because of its shape, does not puncture the curved oviduct. Once the cavity of the rod is in the ovary, it is rotated one full turn and withdrawn. The eggs are retained in the cavity. First, a small amount of physiological saline solution is drawn into a flexible tube. The tube is inserted through the incision into the ovary, and the saline solution is released.
Suction is applied to draw a small number of eggs into the tube.
The diameter and general appearance of the egg are indicators of development. Approximate diameters of ripe eggs of different species of fish are presented in Table 1. The color of ripe eggs also varies with the species of fish. Immature eggs are much smaller than ripe eggs and are usually nearly clear or opaque white or yellow, depending on the fish species. Eggs that have begun to resorb often appear soft or partially deflated rather than firm and round.