Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract
Bivalve populations undergo regular epidemics that weaken or decimate exploited stocks and thus limit aquaculture. These diseases are caused mainly by viruses, bacteria or parasites, and occur primarily during spring and summer. This period of the year also provides favorable conditions for toxic di...
Main Author: | |
---|---|
Other Authors: | , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
Published: |
HAL CCSD
2014
|
Subjects: | |
Online Access: | https://theses.hal.science/tel-02115207 https://theses.hal.science/tel-02115207/document https://theses.hal.science/tel-02115207/file/These-2014-EDSM-Biologie_marine-LASSUDRIE_Malwenn.pdf |
id |
ftunivbrest:oai:HAL:tel-02115207v1 |
---|---|
record_format |
openpolar |
institution |
Open Polar |
collection |
Université de Bretagne Occidentale: HAL |
op_collection_id |
ftunivbrest |
language |
French |
topic |
Harmful Algal Blooms Host-pathogen interactions Marine invertebrate Physiology Immunity Microbiome Micro-algues toxiques Interactions hôte-pathogène Bivalves marins Physiologie Immunité [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology |
spellingShingle |
Harmful Algal Blooms Host-pathogen interactions Marine invertebrate Physiology Immunity Microbiome Micro-algues toxiques Interactions hôte-pathogène Bivalves marins Physiologie Immunité [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology Lassudrie, Malwenn Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract |
topic_facet |
Harmful Algal Blooms Host-pathogen interactions Marine invertebrate Physiology Immunity Microbiome Micro-algues toxiques Interactions hôte-pathogène Bivalves marins Physiologie Immunité [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology |
description |
Bivalve populations undergo regular epidemics that weaken or decimate exploited stocks and thus limit aquaculture. These diseases are caused mainly by viruses, bacteria or parasites, and occur primarily during spring and summer. This period of the year also provides favorable conditions for toxic dinoflagellate blooms, including species of the genus Alexandrium. Thus, the risk of Alexandrium sp. blooms and infectious diseases co-occurring in bivalves is high. However, these micro-algae synthesize and excrete toxins and cytotoxic compounds responsible for physiological changes in bivalves and could lead to an immuno-compromised status.The objective of this thesis is to evaluate the combined effects on bivalve physiology of exposure to the toxic dinoflagellate, Alexandrium sp., and infection by pathogens, through the study of different bivalve - pathogen - Alexandrium sp. tripartite interactions. The results of this work highlight the species-specific nature of these impacts.Thus, exposure to Alexandrium catenella reduces the herpesviruses infection in oyster Crassostrea gigas, whereas the dinoflagellate A. fundyense increases the susceptibility of C. virginica oyster to the parasite Perkinsus marinus, probably via immuno-suppression, as suggested by the partial inhibition of hemocyte responses. Additionally, the effect of a toxic algal bloom on oyster susceptibility to opportunistic diseases when exposed to a new microbial environment (simulating a transfer) was evaluated. Hemocyte responses to a changing microbial environment were suppressed by exposure to A. catenella, although no new bacterial infection was detected.Finally, exposure to pathogens or to a new microbial environment interferes with the processes by which oysters exposed to A. catenella accumulate algal toxins, illustrating the complexity of these interactions. These results provide a better understanding of the involvement of toxic algal blooms in the development of diseases affecting commercial bivalve species, but also of the involvement of the ... |
author2 |
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 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)-Centre National de la Recherche Scientifique (CNRS) Université de Bretagne occidentale - Brest Philippe Soudant |
format |
Doctoral or Postdoctoral Thesis |
author |
Lassudrie, Malwenn |
author_facet |
Lassudrie, Malwenn |
author_sort |
Lassudrie, Malwenn |
title |
Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract |
title_short |
Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract |
title_full |
Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract |
title_fullStr |
Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract |
title_full_unstemmed |
Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract |
title_sort |
combined effects of toxic dinoflagellates of alexandrium genus and pathogens on bivalve physiology abstract |
publisher |
HAL CCSD |
publishDate |
2014 |
url |
https://theses.hal.science/tel-02115207 https://theses.hal.science/tel-02115207/document https://theses.hal.science/tel-02115207/file/These-2014-EDSM-Biologie_marine-LASSUDRIE_Malwenn.pdf |
genre |
Crassostrea gigas |
genre_facet |
Crassostrea gigas |
op_source |
https://theses.hal.science/tel-02115207 Microbiologie et Parasitologie. Université de Bretagne occidentale - Brest, 2014. Français. ⟨NNT : 2014BRES0113⟩ |
op_relation |
NNT: 2014BRES0113 tel-02115207 https://theses.hal.science/tel-02115207 https://theses.hal.science/tel-02115207/document https://theses.hal.science/tel-02115207/file/These-2014-EDSM-Biologie_marine-LASSUDRIE_Malwenn.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1790599480408539136 |
spelling |
ftunivbrest:oai:HAL:tel-02115207v1 2024-02-11T10:03:16+01:00 Combined effects of toxic dinoflagellates of Alexandrium genus and pathogens on bivalve physiology Abstract Effets combinés des dinoflagellés toxiques du genre Alexandrium et d'agents pathogènes sur la physiologie des bivalves Lassudrie, Malwenn 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 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)-Centre National de la Recherche Scientifique (CNRS) Université de Bretagne occidentale - Brest Philippe Soudant 2014-12-10 https://theses.hal.science/tel-02115207 https://theses.hal.science/tel-02115207/document https://theses.hal.science/tel-02115207/file/These-2014-EDSM-Biologie_marine-LASSUDRIE_Malwenn.pdf fr fre HAL CCSD NNT: 2014BRES0113 tel-02115207 https://theses.hal.science/tel-02115207 https://theses.hal.science/tel-02115207/document https://theses.hal.science/tel-02115207/file/These-2014-EDSM-Biologie_marine-LASSUDRIE_Malwenn.pdf info:eu-repo/semantics/OpenAccess https://theses.hal.science/tel-02115207 Microbiologie et Parasitologie. Université de Bretagne occidentale - Brest, 2014. Français. ⟨NNT : 2014BRES0113⟩ Harmful Algal Blooms Host-pathogen interactions Marine invertebrate Physiology Immunity Microbiome Micro-algues toxiques Interactions hôte-pathogène Bivalves marins Physiologie Immunité [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology info:eu-repo/semantics/doctoralThesis Theses 2014 ftunivbrest 2024-01-23T23:40:43Z Bivalve populations undergo regular epidemics that weaken or decimate exploited stocks and thus limit aquaculture. These diseases are caused mainly by viruses, bacteria or parasites, and occur primarily during spring and summer. This period of the year also provides favorable conditions for toxic dinoflagellate blooms, including species of the genus Alexandrium. Thus, the risk of Alexandrium sp. blooms and infectious diseases co-occurring in bivalves is high. However, these micro-algae synthesize and excrete toxins and cytotoxic compounds responsible for physiological changes in bivalves and could lead to an immuno-compromised status.The objective of this thesis is to evaluate the combined effects on bivalve physiology of exposure to the toxic dinoflagellate, Alexandrium sp., and infection by pathogens, through the study of different bivalve - pathogen - Alexandrium sp. tripartite interactions. The results of this work highlight the species-specific nature of these impacts.Thus, exposure to Alexandrium catenella reduces the herpesviruses infection in oyster Crassostrea gigas, whereas the dinoflagellate A. fundyense increases the susceptibility of C. virginica oyster to the parasite Perkinsus marinus, probably via immuno-suppression, as suggested by the partial inhibition of hemocyte responses. Additionally, the effect of a toxic algal bloom on oyster susceptibility to opportunistic diseases when exposed to a new microbial environment (simulating a transfer) was evaluated. Hemocyte responses to a changing microbial environment were suppressed by exposure to A. catenella, although no new bacterial infection was detected.Finally, exposure to pathogens or to a new microbial environment interferes with the processes by which oysters exposed to A. catenella accumulate algal toxins, illustrating the complexity of these interactions. These results provide a better understanding of the involvement of toxic algal blooms in the development of diseases affecting commercial bivalve species, but also of the involvement of the ... Doctoral or Postdoctoral Thesis Crassostrea gigas Université de Bretagne Occidentale: HAL |