41 research outputs found
Genetic and phenotypic diversity of natural and seeded populations of the great scallop Pecten maximus
La coquille Saint-Jacques (Pecten maximus, L.) est un bivalve dâintĂ©rĂȘt scientifique et Ă©conomique. De nombreuses Ă©tudes ont notamment portĂ© sur sa croissance en rĂ©ponse aux variations temporelles ou spatiales de lâenvironnement, mettant Ă profit lâincrĂ©ment journalier de la croissance coquillĂšre. Certaines populations naturelles font lâobjet de soutien Ă la pĂȘche par semis de naissain produits en Ă©closerie, pour compenser les baisses de productivitĂ© constatĂ©es depuis la seconde moitiĂ© du XXĂšme siĂšcle. Cependant, trĂšs peu de donnĂ©es gĂ©nĂ©tiques sont disponibles sur cette espĂšce, ne permettant pas dâestimer lâimpact de ces pratiques en termes de diversitĂ© et de potentiel adaptatif. Dans ce contexte, ma thĂšse sâest articulĂ©e autour de trois axes principaux : (1) une Ă©tude de gĂ©nĂ©tique des populations Ă lâĂ©chelle de lâaire de distribution; (2) une Ă©tude de gĂ©nĂ©tique quantitative pour estimer les bases gĂ©nĂ©tiques de la croissance; (3) le suivi temporel dâune population ensemencĂ©e en Rade de Brest, pour dĂ©terminer lâimpact gĂ©nĂ©tique du programme local de soutien aux populations exploitĂ©es. Les rĂ©sultats montrent quâil existe une forte diffĂ©rentiation entre deux groupes de populations : norvĂ©giennes et atlantiques (de lâAngleterre Ă lâEspagne), globalement concordante avec des diffĂ©rences de croissance prĂ©cĂ©demment observĂ©es, ce qui suggĂšre un base gĂ©nĂ©tique Ă ces derniĂšres. LâĂ©tude de gĂ©nĂ©tique quantitative soutient Ă©galement cette hypothĂšse, montrant une hĂ©ritabilitĂ© modĂ©rĂ©e mais significative des paramĂštres de croissance en rade de Brest. Enfin, un suivi temporel de cohortes en rade de Brest montre un impact limitĂ© du programme de rĂ©ensemencement sur la diversitĂ© gĂ©nĂ©tique, malgrĂ© une estimation des contributions reproductrices des semis relativement Ă©levĂ©e.Lâensemble souligne lâintĂ©rĂȘt de poursuivre lâĂ©tude du potentiel adaptatif des populations de cette espĂšce exploitĂ©e et de lâimpact des rĂ©ensemencements sur les populations naturelles.The great scallop (Pecten maximus, L.) is a marine bivalve of economic and scientific interest. Numerous studies have been done on its growth, notably on growth variation according to temporal or geographic variations based on daily shell growth rings. Some populations are undergoing enhancement programs, by the seeding of hatcheryborn juveniles on natural beds, aiming to compensate for the decline observed since the middle of the 20th century.However, little information was available on the genetics of P. maximus, as a background for evaluating the impact of such programs. In this context, my thesis consists in 3 chapters: (1) a population genetics study along its area of distribution; (2) a quantitative genetics study to estimate genetic basis of growth -related traits; (3) a temporal genetic monitoring of a seeded population in the Bay of Brest to estimate possible impact of the enhancement program. Results showed a strong genetic structure between Norwegian and Atlantic (from U.K. to Spain) populations, coherent with phenotypic differences of growth parameters, suggesting a possible adaptive component of these traits. The quantitative genetic study hints to a similar result by revealing a moderate heritability of growth parameters. Finally, genetic monitoring revealed a limited impact of the population enhancement program, despite relatively high estimations of reproductive contribution of seeded individuals.Overall, these results highlight the scientific interest and the necessity to further study the evolutionary potential of this exploited species and the impact of population enhancement programs
Diversité génétique et phénotypique de populations naturelles ou ensemencées de coquille Saint-Jacques Pecten maximus
The great scallop (Pecten maximus, L.) is a marine bivalve of economic and scientific interest. Numerous studies have been done on its growth, notably on growth variation according to temporal or geographic variations based on daily shell growth rings. Some populations are undergoing enhancement programs, by the seeding of hatcheryborn juveniles on natural beds, aiming to compensate for the decline observed since the middle of the 20th century.However, little information was available on the genetics of P. maximus, as a background for evaluating the impact of such programs. In this context, my thesis consists in 3 chapters: (1) a population genetics study along its area of distribution; (2) a quantitative genetics study to estimate genetic basis of growth -related traits; (3) a temporal genetic monitoring of a seeded population in the Bay of Brest to estimate possible impact of the enhancement program. Results showed a strong genetic structure between Norwegian and Atlantic (from U.K. to Spain) populations, coherent with phenotypic differences of growth parameters, suggesting a possible adaptive component of these traits. The quantitative genetic study hints to a similar result by revealing a moderate heritability of growth parameters. Finally, genetic monitoring revealed a limited impact of the population enhancement program, despite relatively high estimations of reproductive contribution of seeded individuals.Overall, these results highlight the scientific interest and the necessity to further study the evolutionary potential of this exploited species and the impact of population enhancement programs.La coquille Saint-Jacques (Pecten maximus, L.) est un bivalve dâintĂ©rĂȘt scientifique et Ă©conomique. De nombreuses Ă©tudes ont notamment portĂ© sur sa croissance en rĂ©ponse aux variations temporelles ou spatiales de lâenvironnement, mettant Ă profit lâincrĂ©ment journalier de la croissance coquillĂšre. Certaines populations naturelles font lâobjet de soutien Ă la pĂȘche par semis de naissain produits en Ă©closerie, pour compenser les baisses de productivitĂ© constatĂ©es depuis la seconde moitiĂ© du XXĂšme siĂšcle. Cependant, trĂšs peu de donnĂ©es gĂ©nĂ©tiques sont disponibles sur cette espĂšce, ne permettant pas dâestimer lâimpact de ces pratiques en termes de diversitĂ© et de potentiel adaptatif. Dans ce contexte, ma thĂšse sâest articulĂ©e autour de trois axes principaux : (1) une Ă©tude de gĂ©nĂ©tique des populations Ă lâĂ©chelle de lâaire de distribution; (2) une Ă©tude de gĂ©nĂ©tique quantitative pour estimer les bases gĂ©nĂ©tiques de la croissance; (3) le suivi temporel dâune population ensemencĂ©e en Rade de Brest, pour dĂ©terminer lâimpact gĂ©nĂ©tique du programme local de soutien aux populations exploitĂ©es. Les rĂ©sultats montrent quâil existe une forte diffĂ©rentiation entre deux groupes de populations : norvĂ©giennes et atlantiques (de lâAngleterre Ă lâEspagne), globalement concordante avec des diffĂ©rences de croissance prĂ©cĂ©demment observĂ©es, ce qui suggĂšre un base gĂ©nĂ©tique Ă ces derniĂšres. LâĂ©tude de gĂ©nĂ©tique quantitative soutient Ă©galement cette hypothĂšse, montrant une hĂ©ritabilitĂ© modĂ©rĂ©e mais significative des paramĂštres de croissance en rade de Brest. Enfin, un suivi temporel de cohortes en rade de Brest montre un impact limitĂ© du programme de rĂ©ensemencement sur la diversitĂ© gĂ©nĂ©tique, malgrĂ© une estimation des contributions reproductrices des semis relativement Ă©levĂ©e.Lâensemble souligne lâintĂ©rĂȘt de poursuivre lâĂ©tude du potentiel adaptatif des populations de cette espĂšce exploitĂ©e et de lâimpact des rĂ©ensemencements sur les populations naturelles
Diversité génétique et phénotypique de populations naturelles ou ensemencées de coquille Saint-Jacques Pecten maximus
The great scallop (Pecten maximus, L.) is a marine bivalve of economic and scientific interest. Numerous studies have been done on its growth, notably on growth variation according to temporal or geographic variations based on daily shell growth rings. Some populations are undergoing enhancement programs, by the seeding of hatcheryborn juveniles on natural beds, aiming to compensate for the decline observed since the middle of the 20th century.However, little information was available on the genetics of P. maximus, as a background for evaluating the impact of such programs. In this context, my thesis consists in 3 chapters: (1) a population genetics study along its area of distribution; (2) a quantitative genetics study to estimate genetic basis of growth -related traits; (3) a temporal genetic monitoring of a seeded population in the Bay of Brest to estimate possible impact of the enhancement program. Results showed a strong genetic structure between Norwegian and Atlantic (from U.K. to Spain) populations, coherent with phenotypic differences of growth parameters, suggesting a possible adaptive component of these traits. The quantitative genetic study hints to a similar result by revealing a moderate heritability of growth parameters. Finally, genetic monitoring revealed a limited impact of the population enhancement program, despite relatively high estimations of reproductive contribution of seeded individuals.Overall, these results highlight the scientific interest and the necessity to further study the evolutionary potential of this exploited species and the impact of population enhancement programs.La coquille Saint-Jacques (Pecten maximus, L.) est un bivalve dâintĂ©rĂȘt scientifique et Ă©conomique. De nombreuses Ă©tudes ont notamment portĂ© sur sa croissance en rĂ©ponse aux variations temporelles ou spatiales de lâenvironnement, mettant Ă profit lâincrĂ©ment journalier de la croissance coquillĂšre. Certaines populations naturelles font lâobjet de soutien Ă la pĂȘche par semis de naissain produits en Ă©closerie, pour compenser les baisses de productivitĂ© constatĂ©es depuis la seconde moitiĂ© du XXĂšme siĂšcle. Cependant, trĂšs peu de donnĂ©es gĂ©nĂ©tiques sont disponibles sur cette espĂšce, ne permettant pas dâestimer lâimpact de ces pratiques en termes de diversitĂ© et de potentiel adaptatif. Dans ce contexte, ma thĂšse sâest articulĂ©e autour de trois axes principaux : (1) une Ă©tude de gĂ©nĂ©tique des populations Ă lâĂ©chelle de lâaire de distribution; (2) une Ă©tude de gĂ©nĂ©tique quantitative pour estimer les bases gĂ©nĂ©tiques de la croissance; (3) le suivi temporel dâune population ensemencĂ©e en Rade de Brest, pour dĂ©terminer lâimpact gĂ©nĂ©tique du programme local de soutien aux populations exploitĂ©es. Les rĂ©sultats montrent quâil existe une forte diffĂ©rentiation entre deux groupes de populations : norvĂ©giennes et atlantiques (de lâAngleterre Ă lâEspagne), globalement concordante avec des diffĂ©rences de croissance prĂ©cĂ©demment observĂ©es, ce qui suggĂšre un base gĂ©nĂ©tique Ă ces derniĂšres. LâĂ©tude de gĂ©nĂ©tique quantitative soutient Ă©galement cette hypothĂšse, montrant une hĂ©ritabilitĂ© modĂ©rĂ©e mais significative des paramĂštres de croissance en rade de Brest. Enfin, un suivi temporel de cohortes en rade de Brest montre un impact limitĂ© du programme de rĂ©ensemencement sur la diversitĂ© gĂ©nĂ©tique, malgrĂ© une estimation des contributions reproductrices des semis relativement Ă©levĂ©e.Lâensemble souligne lâintĂ©rĂȘt de poursuivre lâĂ©tude du potentiel adaptatif des populations de cette espĂšce exploitĂ©e et de lâimpact des rĂ©ensemencements sur les populations naturelles
Diversité génétique et phénotypique de populations naturelles ou ensemencées de coquille Saint-Jacques Pecten maximus
The great scallop (Pecten maximus, L.) is a marine bivalve of economic and scientific interest. Numerous studies have been done on its growth, notably on growth variation according to temporal or geographic variations based on daily shell growth rings. Some populations are undergoing enhancement programs, by the seeding of hatcheryborn juveniles on natural beds, aiming to compensate for the decline observed since the middle of the 20th century.However, little information was available on the genetics of P. maximus, as a background for evaluating the impact of such programs. In this context, my thesis consists in 3 chapters: (1) a population genetics study along its area of distribution; (2) a quantitative genetics study to estimate genetic basis of growth -related traits; (3) a temporal genetic monitoring of a seeded population in the Bay of Brest to estimate possible impact of the enhancement program. Results showed a strong genetic structure between Norwegian and Atlantic (from U.K. to Spain) populations, coherent with phenotypic differences of growth parameters, suggesting a possible adaptive component of these traits. The quantitative genetic study hints to a similar result by revealing a moderate heritability of growth parameters. Finally, genetic monitoring revealed a limited impact of the population enhancement program, despite relatively high estimations of reproductive contribution of seeded individuals.Overall, these results highlight the scientific interest and the necessity to further study the evolutionary potential of this exploited species and the impact of population enhancement programs.La coquille Saint-Jacques (Pecten maximus, L.) est un bivalve dâintĂ©rĂȘt scientifique et Ă©conomique. De nombreuses Ă©tudes ont notamment portĂ© sur sa croissance en rĂ©ponse aux variations temporelles ou spatiales de lâenvironnement, mettant Ă profit lâincrĂ©ment journalier de la croissance coquillĂšre. Certaines populations naturelles font lâobjet de soutien Ă la pĂȘche par semis de naissain produits en Ă©closerie, pour compenser les baisses de productivitĂ© constatĂ©es depuis la seconde moitiĂ© du XXĂšme siĂšcle. Cependant, trĂšs peu de donnĂ©es gĂ©nĂ©tiques sont disponibles sur cette espĂšce, ne permettant pas dâestimer lâimpact de ces pratiques en termes de diversitĂ© et de potentiel adaptatif. Dans ce contexte, ma thĂšse sâest articulĂ©e autour de trois axes principaux : (1) une Ă©tude de gĂ©nĂ©tique des populations Ă lâĂ©chelle de lâaire de distribution; (2) une Ă©tude de gĂ©nĂ©tique quantitative pour estimer les bases gĂ©nĂ©tiques de la croissance; (3) le suivi temporel dâune population ensemencĂ©e en Rade de Brest, pour dĂ©terminer lâimpact gĂ©nĂ©tique du programme local de soutien aux populations exploitĂ©es. Les rĂ©sultats montrent quâil existe une forte diffĂ©rentiation entre deux groupes de populations : norvĂ©giennes et atlantiques (de lâAngleterre Ă lâEspagne), globalement concordante avec des diffĂ©rences de croissance prĂ©cĂ©demment observĂ©es, ce qui suggĂšre un base gĂ©nĂ©tique Ă ces derniĂšres. LâĂ©tude de gĂ©nĂ©tique quantitative soutient Ă©galement cette hypothĂšse, montrant une hĂ©ritabilitĂ© modĂ©rĂ©e mais significative des paramĂštres de croissance en rade de Brest. Enfin, un suivi temporel de cohortes en rade de Brest montre un impact limitĂ© du programme de rĂ©ensemencement sur la diversitĂ© gĂ©nĂ©tique, malgrĂ© une estimation des contributions reproductrices des semis relativement Ă©levĂ©e.Lâensemble souligne lâintĂ©rĂȘt de poursuivre lâĂ©tude du potentiel adaptatif des populations de cette espĂšce exploitĂ©e et de lâimpact des rĂ©ensemencements sur les populations naturelles
Diversité génétique et phénotypique de populations naturelles ou ensemencées de coquille Saint-Jacques Pecten maximus
The great scallop (Pecten maximus, L.) is a marine bivalve of economic and scientific interest. Numerous studies have been done on its growth, notably on growth variation according to temporal or geographic variations based on daily shell growth rings. Some populations are undergoing enhancement programs, by the seeding of hatcheryborn juveniles on natural beds, aiming to compensate for the decline observed since the middle of the 20th century.However, little information was available on the genetics of P. maximus, as a background for evaluating the impact of such programs. In this context, my thesis consists in 3 chapters: (1) a population genetics study along its area of distribution; (2) a quantitative genetics study to estimate genetic basis of growth -related traits; (3) a temporal genetic monitoring of a seeded population in the Bay of Brest to estimate possible impact of the enhancement program. Results showed a strong genetic structure between Norwegian and Atlantic (from U.K. to Spain) populations, coherent with phenotypic differences of growth parameters, suggesting a possible adaptive component of these traits. The quantitative genetic study hints to a similar result by revealing a moderate heritability of growth parameters. Finally, genetic monitoring revealed a limited impact of the population enhancement program, despite relatively high estimations of reproductive contribution of seeded individuals.Overall, these results highlight the scientific interest and the necessity to further study the evolutionary potential of this exploited species and the impact of population enhancement programs.La coquille Saint-Jacques (Pecten maximus, L.) est un bivalve dâintĂ©rĂȘt scientifique et Ă©conomique. De nombreuses Ă©tudes ont notamment portĂ© sur sa croissance en rĂ©ponse aux variations temporelles ou spatiales de lâenvironnement, mettant Ă profit lâincrĂ©ment journalier de la croissance coquillĂšre. Certaines populations naturelles font lâobjet de soutien Ă la pĂȘche par semis de naissain produits en Ă©closerie, pour compenser les baisses de productivitĂ© constatĂ©es depuis la seconde moitiĂ© du XXĂšme siĂšcle. Cependant, trĂšs peu de donnĂ©es gĂ©nĂ©tiques sont disponibles sur cette espĂšce, ne permettant pas dâestimer lâimpact de ces pratiques en termes de diversitĂ© et de potentiel adaptatif. Dans ce contexte, ma thĂšse sâest articulĂ©e autour de trois axes principaux : (1) une Ă©tude de gĂ©nĂ©tique des populations Ă lâĂ©chelle de lâaire de distribution; (2) une Ă©tude de gĂ©nĂ©tique quantitative pour estimer les bases gĂ©nĂ©tiques de la croissance; (3) le suivi temporel dâune population ensemencĂ©e en Rade de Brest, pour dĂ©terminer lâimpact gĂ©nĂ©tique du programme local de soutien aux populations exploitĂ©es. Les rĂ©sultats montrent quâil existe une forte diffĂ©rentiation entre deux groupes de populations : norvĂ©giennes et atlantiques (de lâAngleterre Ă lâEspagne), globalement concordante avec des diffĂ©rences de croissance prĂ©cĂ©demment observĂ©es, ce qui suggĂšre un base gĂ©nĂ©tique Ă ces derniĂšres. LâĂ©tude de gĂ©nĂ©tique quantitative soutient Ă©galement cette hypothĂšse, montrant une hĂ©ritabilitĂ© modĂ©rĂ©e mais significative des paramĂštres de croissance en rade de Brest. Enfin, un suivi temporel de cohortes en rade de Brest montre un impact limitĂ© du programme de rĂ©ensemencement sur la diversitĂ© gĂ©nĂ©tique, malgrĂ© une estimation des contributions reproductrices des semis relativement Ă©levĂ©e.Lâensemble souligne lâintĂ©rĂȘt de poursuivre lâĂ©tude du potentiel adaptatif des populations de cette espĂšce exploitĂ©e et de lâimpact des rĂ©ensemencements sur les populations naturelles
Genotype_clean-GENEPOP
This file contain the same data as the sheet "genotypes_clean" of the associated excel file, but in GENEPOP (Raymont & Rousset 1995) format. This is provided for convenience of use.
Below are the equivalence of population names between files.
POPULATION ID GENEPOP ID
Hatch12 CAu001
Wild12 NAu001
Hatch07 PmE001
Hatch09 PmE166
Wild07 PmN001
Wild09 PmN10
Pecten-Msat-Genotypes
File: Pecten-Msat-Genotype.xls
Contain all the data in excel formating, ready to be converted by a software such as CREATE (Coombs et al. 2008)
First sheet ("genotype_raw"): raw data (all individuals genotyped at all microsatellite loci)
Each line is an individual animal.Each columns after population and individual identifier contain one allele.
Both alleles for a given locus are given consecutively (see header row).
For details on microatellites primers, PCR protocols and marker statistics please see Morvezen et al. 2013 and Morvezen et al. 2016
Population names are abbreviated in the publication for simplicity.
Name equivalences
Hatch=Hatchery=H
Wild=W
Second sheet ("genotypes_cleaned")
Same as the first sheet minus indivudals with >50% missing data. This is the dataset used as input for all analyses in the publication
Genetic structure of a commercially exploited bivalve, the great scallop pecten maximus, along the european coasts
International audienceThe great scallop Pecten maximus is harvested in several European countries and fisheries targeting this species are severely regulated by fishing quotas. In addition, hatchery-based population enhancement has been developed in some countries to provide alternative or complementary production. The genetic structure of wild populations of P. maximus and the potential impact of aquaculture on the genetic diversity of this species remains poorly documented. In this study, we explored the genetic structure of P. maximus using 12 microsatellite markers, considering 14 populations sampled from Galicia (Spain) to the North of Norway, and one population of Pecten jacobaeus (L., 1758) from the Lion Gulf (Mediterranean Sea). Results indicated a clear differentiation between Norwegian and Atlantic (from Ireland to Spain) populations, but very little to no difference between populations within these two groups. A decrease of the genetic diversity was observed with latitude. No significant reduction of the genetic diversity was observed in the Bay of Brest, where hatchery-based population enhancement has been performed intensively since 1983. Our results are discussed in the light of the inferred recent evolutionary history, phylogeography and connectivity of populations in Europe, and of the phenotypic variability reported in previous studies between northern and southern populations
Development of genomic predictions for female reproduction traits in rainbow trout (Oncorhynchus mykiss)
International audienc
Effects of bioactive extracellular compounds and paralytic shellfish toxins produced by Alexandrium minutum on growth and behaviour of juvenile great scallops Pecten maximus
Dinoflagellates of the genus Alexandrium are a major cause of harmful algal blooms (HABs) that have increasingly disrupted coastal ecosystems for the last several decades. Microalgae from the genus Alexandrium are known to produce paralytic shellfish toxins (PST) but also bioactive extracellular compounds (BEC) that can display cytotoxic, allelopathic, ichtyotoxic or haemolytic effects upon marine organisms. The objective of this experimental study was to assess the effects of PST and BEC produced by A. minutum upon juvenile great scallops Pecten maximus. Scallops were exposed for one week to two different strains of A. minutum, the first producing both PST and BEC and the second producing only BEC. Escape response to starfish, daily shell growth, histological effects, and accumulation of PST were recorded after one week of exposure, and after two subsequent weeks of recovery. Daily shell growth was delayed three days in scallops exposed to the BEC-producing A. minutum strain, probably during the three first days of exposure. An increase of reaction time to predators was observed in scallops exposed to the BEC condition, suggesting that BEC may have altered sensing processes. Scallops exposed to PST displayed a less-efficient escape response and muscular damage which could reflect the effects of paralytic toxins upon the nervous system of scallops. This study demonstrates contrasting effects of the distinct toxic compounds produced by A. minutum upon marine bivalves, thus highlighting the importance to better characterize these extracellular, bioactive compounds to better understand responses of other marine organisms