Fig. 3

Hematoxylin and eosin staining of paraffinized ovarian sections from FR1 and FR2 females showing the generation of MOFs. a Ovaries from FR1 and FR2 females are mainly characterized by many growing follicles that are adjacent to each other, indicating their fusion. b-d Follicles in the process of merging (arrowheads); we can see in (d) the displacement of the oocyte from one follicle into the second one. e Primordial follicle with two oocytes. f primordial follicle with three oocytes. g Primary follicle with two oocytes, (h) Primary follicle with three oocytes. i Secondary follicle with two oocytes. (J) Antral follicle with two oocytes; (k) Antral follicle with three oocytes; (l) Antral follicle merging with an early secondary follicle (arrowhead), the large arrow is showing the oocyte position of the antral follicle. Scale bar = 200 μm