Primordial germ cells in aves - Review -

Relationship between PGCs Settle and Gonad Development in the Early Chicken Embryo

“…The PGCs in males scattered randomly within a developing seminiferous tubule until 13 days of incubation, after this period, they began to differeniate into spermatogonis, in contrast to the embryo of the male, the sexual differentiation of the female embryo occurs in the left ovary at 8 days of incubation, the PGCs began to active meiotic division, forming oogonia at this stage, the right ovary always degradate after birth. But the result of this experiment showed that, at the same incubation condition, sexual differentiation began at 6 days of incubation, that did not in common withHan's (1994) report, perhaps owed to specious, ample time, incubation condition difference, the result of this experiment revealed that, many PGCs are located in the gonad at 6 days of incubation, the classic PGCs cannot be found in the gonad at 7 days of incubation, they had differentiated into female or male germinal cells, which indicated that the structure of the germinal ridge appeared at 6 days of incubation, PGCs began to differentiate to oogonium or spermagonic at 7 days of incubation.…”

“…Concluded by the testis cord formed at 7 days of incubation, the testis perhaps began to differentiate at 6 days of incubation, because the testis and the ovary should formed simultaneously. After appearing the sexual differentiation, PGCs began to division, the female appeared at 8-11 days of incubation, the male appeared at 13-15 days of incubation(Han et. al., 1994;Han et al, 1995).…”