Ovary of an adult female harbour porpoise showing signs of former ovulation and tertiary follicles.

(A): Corpus luteum (asterisk) and corpus albicans (arrow). (B): Corpus luteum as a protuberance on the ovarian surface (C), (D): Histological section through a Corpus luteum showing luteal cells. Staining: H&E. (E): Histological section showing the Cumulus oophorus with the oocyte surrounded by the Zona pelucida and Corona radiata. Asterisk: Antrum folliculare. Staining: H&E. (F): Histological section through a Corpus albicans showing an increased amount of connective tissue (asterisk). Staining: Masson´s Trichrome.