Identification of Primordial Germ Cells in Early Pheasant (Phasianus Colchicus) Embryo

The aim of this study is identification of primordial germ cells during their circulation in the blood stream and migration to the primary gonads in pheasant embryo. The blood was taken from stages 14-17 and genital ridge tissue was taken from stages 20-21 Hamburger & Hamilton. Primary gonads were acquired from stages 28-30 Hamburger & Hamilton. Primordial germ cells have been recognized by using histochemical and immunostaining methods. The current article specified that these cells are distinguishable based on their relatively large size, large nuclei and cytoplasm with defined boundaries. In blood smear, such cells were negative for alkaline phosphatase, while the circulating primordial germ cells were negative for stage-specific embryonic antigen-1 (SSEA-1). Further, the Periodic Acid-Schiff staining was negative or very weak. These cells showed a very weak or negative reaction to staining with Alcian blue. At stages 20-30 Hamburger & Hamilton, primitive germ cells might not be distinguished by alkaline phosphatase and SSEA1 immunostaining. Alcian blue and Periodic Acid-Schiff staining was either negative or very weak in these cells. According to the results of this study, primordial germ cells in all stages showed very weak or negative reactions to different histochemical and immunostaining techniques. We recommend that the use of routine hematoxylin and eosin staining yields better results for primordial germ cells identification.