Analyse expérimentale de la régulation du nombre des cellules germinales après déficience gonadique chez le poulet Available to Purchase

Colonization of the genital ridges by germ cells was quantitatively studied in control chick embryos killed at stages 25–29, and in embryos in which a surgical excision of the gonad presumptive area was made previously on the second day.

In operated embryos which show a more or less perfect agenesis of one gonad, the number of germ cells counted in genital ridges is lower than the number of germ cells estimated in the same stages of control embryos. The deficit is greater for left gonadic agenesis. The decrease in the total number of germ cells is essentially due to a reduction in the cells colonizing the deficient gonad. There is no excess of germ cells observed in the control gonad.

Accordingly, a right side operation strengthens the asymmetry of germ cells distribution, whereas a left side one reduces it.

Thus, in birds the regulation of the number of germ cells and the quantitative control of colonisation of the gonads is at the gonad level.