Fig. 1

Angiogenesis in bovine ovarian tissue cultured on traumatized chorioallantoic membrane (CAM) of chick embryos. a Windowing (1 × 2 cm) in eggshell on embryonic day (d) 3 (7 days before culture). b Grafting of bovine ovarian tissue (white arrowhead) on embryonic day 10 (culture day 0). c-e Blood vessel movement (pinwheel-like) around the ovarian tissue on culture days 1, 3 and 5. f-h Histological examination of the ovarian tissue on culture days 1, 3 and 5. Asterisk (*) and double asterisk (**) represent CAM tissue and bovine ovarian tissue respectively. i-k Higher magnification of dotted areas in panels F-H. Black solid arrows indicate avian blood vessels characterized by nucleated red blood cells in bovine ovarian tissues. White bars (c-e) and black bars (f-k) represent 2 mm and 50 μm, respectively