Postnatal Histological Changes of the Ovary in the Female Rabbit (Oryctolagus cuniculus)
DOI:
https://doi.org/10.48165/ijapm.2026.42.00.19Keywords:
Development, Growth, Ovary, Postnatal, RabbitAbstract
The present study demonstrated that the general histological architecture of both the right and left ovaries in rabbits at different ages (1 month, 7 months, and 1 year) was generally similar. The ovary consisted of two main regions: the cortex and the medulla. The cortex was covered by a thin connective tissue capsule lined with a germinal epithelium composed of simple cuboidal cells characterized by clear cytoplasm and vertically oriented club-shaped nuclei showing mitotic activity. Beneath the epithelium, the tunica albuginea was observed as a slim collagenous layer of dense irregular connective tissue. Primordial follicles were abundant in 1-month- and 7-month-old rabbits but decreased markedly in 1-year-old rabbits. Primary follicles were numerous in all age groups, whereas secondary follicles were fewer in 1-month-old rabbits and increased significantly in older animals. Tertiary follicles and numerous corpora lutea were mainly observed in 7-month- and 1-year-old rabbits, indicating increased reproductive activity with age. Histomorphometric analysis revealed age-related variations in ovarian structures. The thickness of the ovarian capsule and cortical layer increased with age, reaching the highest values in 1-year-old rabbits and the lowest in 1-month-old rabbits. In contrast, the medullary layer was thickest in the youngest group and thinnest in the 7-month-old rabbits. Follicular diameter also varied according to age; primary follicles were larger in 7-month-old rabbits, while secondary and mature follicles exhibited the greatest diameters in the oldest age group. These findings suggest that ovarian development and follicular maturation progress significantly with age, reflecting enhanced ovarian functional activity in mature rabbits.
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