title: Spatial and temporal dynamics of mass mortalities in oysters is influenced by energetic reserves and food quality.
abstract: Although spatial studies of diseases on land have a long history, far fewer have been made on aquatic diseases. Here, we present the first large-scale, high-resolution spatial and temporal representation of a mass mortality phenomenon cause by the Ostreid herpesvirus (OsHV-1) that has affected oysters (Crassostrea gigas) every year since 2008, in relation to their energetic reserves and the quality of their food. Disease mortality was investigated in healthy oysters deployed at 106 locations in the Thau Mediterranean lagoon before the start of the epizootic in spring 2011. We found that disease mortality of oysters showed strong spatial dependence clearly reflecting the epizootic process of local transmission. Disease initiated inside oyster farms spread rapidly beyond these areas. Local differences in energetic condition of oysters, partly driven by variation in food quality, played a significant role in the spatial and temporal dynamics of disease mortality. In particular, the relative contribution of diatoms to the diet of oysters was positively correlated with their energetic reserves, which in turn decreased the risk of disease mortality.
authors.affiliation: Ifremer, Laboratoire Environnement Ressource du Languedoc Roussillon, Bd Jean Monnet, Sète, France ; UMR LEMAR Ifremer/CNRS/UBO/IRD, Technopole de Brest-Iroise, Plouzané, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Pernet
authors.affiliation: Ifremer, Laboratoire Environnement Ressource du Languedoc Roussillon, Bd Jean Monnet, Sète, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Lagarde
authors.affiliation: Geovariances, Avon, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Jeannée
authors.affiliation: Université Laval, Département de mathématiques et de statistique, Pavillon Alexandre-Vachon, Québec, Québec, Canada.
authors.forename: Gaetan
authors.initials: G
authors.lastname: Daigle
authors.affiliation: Ifremer, Laboratoire Environnement Ressource du Languedoc Roussillon, Bd Jean Monnet, Sète, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Barret
authors.affiliation: Ifremer, Laboratoire Environnement Ressource du Languedoc Roussillon, Bd Jean Monnet, Sète, France.
authors.forename: Patrik
authors.initials: P
authors.lastname: Le Gall
authors.affiliation: UMR LEMAR Ifremer/CNRS/UBO/IRD, Technopole de Brest-Iroise, Plouzané, France.
authors.forename: Claudie
authors.initials: C
authors.lastname: Quere
authors.affiliation: Ifremer, Laboratoire Environnement Ressource du Languedoc Roussillon, Bd Jean Monnet, Sète, France.
authors.forename: Emmanuelle Roque
authors.initials: ER
authors.lastname: D'orbcastel
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D004734:Energy Metabolism; D005227:Fatty Acids / Q000378:metabolism; D005502:Food; D020387:Food Chain; D005602:France; D005843:Geography; D006564:Herpesviridae / Q000235:genetics; D010125:Ostreidae / Q000502:physiology*; D016016:Proportional Hazards Models; D012044:Regression Analysis; D062211:Spatio-Temporal Analysis; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D015415:Biomarkers; D004279:DNA, Viral; D005227:Fatty Acids