Prenatal developmental study of the ovaries of the Egyptian Baladi rabbits (Oryctolagus cuniculus)

Prenatal developmental study of the ovaries of the Egyptian Baladi rabbits (Oryctolagus cuniculus)

This study was carried out to find out the histological changes of the ovaries of the Baladi rabbits at different prenatal periods. A hundred Baladi rabbit embryos and fetuses were used in this study. The ethically approved pregnant rabbits were euthanized, dissected and, subsequently, the embryos and fetuses were collected. The samples were fixed with modified Davidson's fixative and 10% neutral buffered formalin for 24 to 48 hours and then subjected to routine paraffin embedding technique. They sections were stained by hematoxylin-eosin, Crossman’s trichrome and Gomori's reticulin stains. Stained sections were examined by light microscope. The study revealed that the ovarian differentiation with the appearance of its cortex and medulla occurred at the 19th day postconception. The oogonial nests were observed within the ovarian cortex at the 24th day of fetal rabbit life. The primitive tunica albuginea ovarii could be recognized at the 28th day postconception. No primordial follicle occurred throughout the fetal rabbit life.

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