The Position of Germinal Disc during the Rapid Growing Phase of the Ovarian Follicles in the Japanese Quail

Abstract

The relative position of the germinal disc on the surface of F₁ to F₅ ovarian follicles were investigated in regularly laying Japanese quail.
At the onset of rapid follicular growth, the germinal disc was found at any positions other than the juxtra-stigma region. The distance between the stalk and the germinal disc remained fairly constant during maturation of follicles. Consequently, in the follicles larger than the F₃ stage, the germinal disc migrated away from the stigma. This change in the position of the germinal disc would protect germ cells from expecting physical and chemical damages at the rupture of the follicle.