Fig. 1. Apoptotic oocytes in the ovary-like gonadal tissue. Sections of undifferentiated ovary-like gonads were made at 10 (A,B), 15 (C,D), 17 (E,F) and 19 (G,H) days post-hatching. Apoptotic oocytes were detected by TUNEL staining (B,D,F,H) and were counterstained with haematoxylin and eosin (A,C,E,G). Only a few TUNEL-positive oocytes (black and white arrowheads) were found at 15 days post-hatching (C,D), and apoptotic oocytes were often observed at 17 and 19 days post-hatching (E–H). A TUNEL-positive somatic cell (red arrowhead) was detected in the ovarian cavity at 19 days post-hatching (G,H). ed, early diplotene oocyte; go, gonocyte; oc, ovarian cavity; pa, pachytene oocyte; po, perinucleolar oocyte; sc, somatic cell. Scale bars, 20 µm.
