Reproductive effort of Pacific oysters: a trait associated with susceptibility to summer mortality.

• Published in: Aquaculture
• Main Authors: Huvet, Arnaud, Normand, Julien, Fleury, Elodie, Quillien, Virgile, Fabioux, Caroline, Boudry, Pierre
• Other Authors: Physiologie et Ecophysiologie des Mollusques Marins (PE2M), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire de Génétique et Pathologie (LGP), 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), Université de Brest (UBO)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: Summer mortality; Bivalve mollusc; Crassostrea gigas; Reproduction; Selected lines; [SDE]Environmental Sciences; Pacific; Pacific oyster
• Online Access: https://hal.univ-brest.fr/hal-00645613; https://doi.org/10.1016/j.aquaculture.2010.03.022

Texte intégral accessible à partir de Archimer: http://archimer.ifremer.fr/doc/00006/11766/8502.pdf International audience Summer mortality of the Pacific oyster Crassostrea gigas is the result of a complex interaction between oysters, their environment and their pathogens. The physiological status of an oyster, especially its reproductive status, is suspected to play a significant role in the outcome of this interaction. As genetic variability exists for susceptibility to summer mortality, resistant (R) and susceptible (S) oyster lines were produced using a divergent selection scheme. The present paper reports a histological study on gonad area, which is representative of reproductive effort, in randomly chosen five R and five S oyster lines. The R lines showed a significantly lower gonad area than the S lines (P < 0.001), with an estimated mean difference of 12.5%, whereas, taken together, R and S lines showed a similar distribution of gametogenic stages when sampled. Considering the lines separately, the significant difference in gonad area went up to 24% between R and S lines. The present data confirm and strengthen the negative correlation between reproductive effort and resistance to summer mortality observed in previous studies. Summer mortality of C. gigas in France could, therefore, be partly due to a physiological disorder and metabolic disturbance in oysters associated with their reproductive effort. This does not, however, imply a direct link between the cost of reproduction and mortality because other causal factors, such as pathogenic agents, could be the primary causal factors.