Comparison of quantitative gonad maturation scales in a temperate oyster (Crassostrea gigas) and a sub-tropical oyster (Crassostrea corteziensis)

• Published in: Invertebrate Reproduction & Development
• Main Authors: Rodriguez-Jaramillo, C., Ibarra, A. M., Soudant, Philippe, Palacios, E.
• Other Authors: Centro de Investigaciones Biologicas del Noroeste Mexico (CONACYT-CIBNOR), Consejo Nacional de Ciencia y Tecnología Mexico (CONACYT), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: ACL; Pacific oyster; Oyster; Reproduction; Histology; bay; vitellogenesis; biochemical-composition; broodstock management; Female; invertebrate reproduction; maturity; mollusk; northwest coast; oocyte size; reproductive-cycle; seasonal-variation; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Pacific; Crassostrea gigas
• Online Access: https://hal.archives-ouvertes.fr/hal-02613074; https://doi.org/10.1080/07924259.2017.1315341

WOS:000406370200003 Quantitative scales to evaluate maturity of female gonads were compared for a temperate oyster, Crassostrea gigas and a tropical oyster, Crassostrea corteziensis grown in the same locality. C. gigas had well-defined maturation and spawning periods and a resting phase in winter; in C. corteziensis mature individuals occurred most of the year and there were several spawning peaks. Of the quantitative scales used here, average oocyte diameter and gonad coverage area, much used for C. gigas, and ovary maturity index, less used, were inadequate to distinguish the reproductive pattern of C. corteziensis, since they both skewed the degree of maturation in vitellogenic stages in favor of C. gigas. Maximum oocyte diameter and maximum cytoplasm area were different among species at vitellogenic stages and also in previtellogenic stages. Nucleus: cytoplasm ratio was significantly different in previtellogenic and spawned stages between C. gigas and C. corteziensis. The Index of gonadal development was skewed in favor of C. gigas in postvitellogenic stage. The only scale that was comparable between species was reproductive potential, but it also was one of the most laborious. Other ordinal scales commonly used, such as a visual external evaluation of the gonad, only classified correctly a quarter of the stages.