Morphological and Morphometric Aspects of Crassostrea rhizophorae (Guilding, 1828) Oocytes in Three Stages of the Gonadal Cycle

Crassostrea rhizophorae (Guilding, 1828) is one of the tropical species of oysters cultivated on the Brazilian shore. Despite its high commercial value, there is no information on the gonadal characteristics during the reproductive stages of this species. The objective of this work was to analyze the morphology and morphometry of Crassostrea rhizophorae oocytes and follicles in three stages of the gonadal cycle. Were analized histological sections of gonads considering that the oocytes presented visible nuclei and nucleoli, it was observed three gonadal cycle stages: early gametogenesis, growth and maturation. In the early gametogenesis stage, follicles and oocytes presented diameters of 180.29 ( 41.91) and 18.66 ( 6.85) m, respectively, and presence of large amount of connective tissue and previtellogenic oocyte. In the growth stage, follicles and oocytes presented diameters of 218.02 ( 43.19) and 25.92 ( 9.94) m, respectively, this stage was characterized by a small amount of interfollicular connective tissue with vitellogenic oocyte predominate. In the maturation stage, follicles and oocytes presented diameters of 298.16 ( 99.24) and 35.27 ( 6.2) m, respectively, and presence of large number of mature oocytes. We concluded that during culture Crassostrea rhizophorae tolerates the influence of intrinsic and extrinsic factors and does not undergo significant changes in reproductive activity.