Summer mortality of hatchery-produced Pacific oyster spat (Crassostrea gigas). I. Estimation of genetic parameters for survival and growth

• Published in: Aquaculture
• Main Authors: Degremont, Lionel, Ernande, Bruno, Bédier, Edouard, Boudry, Pierre
• Other Authors: Laboratoire de Génétique et Pathologie (LGP), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire Ressources Halieutiques (LRH), Laboratoire Laboratoire Environnement Ressources Morbihan Pays de Loire (LER/MPL)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2007
• Subjects: smoking-process; smoke-generation; PAH-; organoleptic-properties; [SDV.SA.STP]Life Sciences [q-bio]/Agricultural sciences/Sciences and technics of fishery; [SDV.BA]Life Sciences [q-bio]/Animal biology; Pacific; Crassostrea gigas; Pacific oyster
• Online Access: https://hal.archives-ouvertes.fr/hal-00156731; https://hal.archives-ouvertes.fr/hal-00156731/document; https://hal.archives-ouvertes.fr/hal-00156731/file/publication-2457.pdf; https://doi.org/10.1016/j.aquaculture.2006.10.025

International audience The multidisciplinary project "MOREST" aims to improve our understanding of causes of summer mortality in Crassostrea gigas juveniles in France and to reduce its impact on oyster production. As pail of the MOREST project, 43 full-sib families nested within 17 half-sib families were produced, planted out and tested in 3 sites during summer 2001 to assess to what extent genetic variability exists for this trait. A strong genetic basis was found for survival as narrow-sense heritability estimates ranged from 0.47 to 1.08, with higher values in sites where summer mortality was higher. Genetic correlations across sites were positive and very high for survival, indicating no genotype by environment interaction. In contrast, lower genetic variation was observed for growth in all sites. Finally, genetic correlations between growth and survival were low, in all sites. Selective breeding in a single site should therefore be an efficient means of improving survival in oysters less than one year old along the French Atlantic and Channel coastlines with only very limited effects on growth. As yield mostly depends on survival and growth, this approach should significantly improve harvestable yield. Possible reasons why a high genetic variance for survival appears to be maintained in wild populations are discussed. (c) 2006 Elsevier B.V. All rights reserved.