Determination of the Ovarian Stages in Wild Persian Sturgeon,

In the present study we investigated the histological changes in the ovary of 35 female Persian sturgeon. Ovarian samples were taken from the females stained with hematoxylin and eosin (H&E) staining and sexual maturity was determined by examining the sections under a light microscope. Four developmental stages of ovary including cortical alveoli formation stage (ΙΙ), vitellogenic stage (ΙII), mature stage (IV) and ovulation stage (V) were recognized during development. The gonadosomatic index (GSI) of female Persian sturgeon gradually increased during the development of ovary. The lowest GSI was recorded in stage II (2.57 ± 0.28) and the highest GSI was shown in stage V (23.58 ± 1.08). Therefore, GSI may be useful to determining maturity stages; however histological experiments of ovaries should be considered as the most accurate method for all stages