The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean
Apicomplexans comprise a group of unicellular, often highly pathogenic, obligate parasites infecting both vertebrates and invertebrates, exploiting either one (monoxenous) or two hosts (heteroxenous) to complete a full reproductive life cycle. Their pathogenicity varies considerably between species...
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University of Iceland, School of Engineering and Natural Sciences, Faculty of Life and Environmental Sciences
2018
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Online Access: | https://hdl.handle.net/20.500.11815/985 |
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ftopinvisindi:oai:opinvisindi.is:20.500.11815/985 2023-05-15T16:46:35+02:00 The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean Eðli og meinvirkni sníkjudýra af fylkingu Apicomplexa í tengslum við stórfelld afföll í stofnum hörpudisks (Bivalvia: Pectinidae) í Norður Atlantshafi Kristmundsson, Árni Líf- og umhverfisvísindadeild (HÍ) Faculty of Life and Environmental Sciences (UI) Verkfræði- og náttúruvísindasvið (HÍ) School of Engineering and Natural Sciences (UI) Háskóli Íslands University of Iceland 2018-10-30 https://hdl.handle.net/20.500.11815/985 en eng University of Iceland, School of Engineering and Natural Sciences, Faculty of Life and Environmental Sciences Árni Kristmundsson, 2018, The nature and pathogenicity of apicomplexans infecting scallop (Bivalvia: Pectinidae) populations in the North-Atlantic Ocean, PhD dissertation, Faculty of Life and Environmental Sciences, School of Engineering and Natural Sciences, University of Iceland 978-9935-9438-2-8 https://hdl.handle.net/20.500.11815/985 info:eu-repo/semantics/openAccess Scallop Whelk Apicomplexa Mollusc diseases Epidemiology Skeldýr Hörpudiskur Sníklar Sjúkdómar Faraldsfræði Norður-Atlantshaf Doktorsritgerðir info:eu-repo/semantics/doctoralThesis 2018 ftopinvisindi https://doi.org/20.500.11815/985 2022-11-18T06:51:41Z Apicomplexans comprise a group of unicellular, often highly pathogenic, obligate parasites infecting both vertebrates and invertebrates, exploiting either one (monoxenous) or two hosts (heteroxenous) to complete a full reproductive life cycle. Their pathogenicity varies considerably between species and/or their hosts but as most species are obligate, intracellular parasites they cause some level of pathology in all cases. In relation to abnormal mortality events experienced in scallop populations in the North Atlantic, four different species of scallops, i.e. Iceland scallop, queen scallop, king scallop and sea scallop, were examined for infectious agents, with the aim of shedding light on these events. Most emphasis was made on the Iceland scallop stock in Icelandic waters that unexpectedly collapsed during the 2000s. Its health status was annually monitored for 14 years. In addition to the scallops, whelks and other mollusc species were examined at later stages in the study, in context with presumable life cycle of a pathogen observed. Two different apicomplexan species, both of which appeared to be previously unknown, were identified: 1) Margolisiella islandica, a novel species infecting the heart auricles and highly prevalent in Iceland scallop, without causing any significant pathology, but absent in the three other scallop species. It is a monoxenous species, with all life stages present in a single host, i.e. the Iceland scallop. 2) Initially anonymous species, infecting muscular- and connective tissues, was found in all four scallop species examined. Except for scallops from the UK, infections were generally heavy, causing severe histopathological changes leading to significant reduction in the general condition of the scallops, especially adductor muscles, which become abnormally reduced and discoloured. Furthermore, it hampers normal gonad development, at least in the Iceland scallop. Molecular studies and in situ hybridization, revealed that it is conspecific with Merocystis kathae, an apicomplexan ... Doctoral or Postdoctoral Thesis Iceland North Atlantic Opin vísindi (Iceland) |
institution |
Open Polar |
collection |
Opin vísindi (Iceland) |
op_collection_id |
ftopinvisindi |
language |
English |
topic |
Scallop Whelk Apicomplexa Mollusc diseases Epidemiology Skeldýr Hörpudiskur Sníklar Sjúkdómar Faraldsfræði Norður-Atlantshaf Doktorsritgerðir |
spellingShingle |
Scallop Whelk Apicomplexa Mollusc diseases Epidemiology Skeldýr Hörpudiskur Sníklar Sjúkdómar Faraldsfræði Norður-Atlantshaf Doktorsritgerðir Kristmundsson, Árni The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean |
topic_facet |
Scallop Whelk Apicomplexa Mollusc diseases Epidemiology Skeldýr Hörpudiskur Sníklar Sjúkdómar Faraldsfræði Norður-Atlantshaf Doktorsritgerðir |
description |
Apicomplexans comprise a group of unicellular, often highly pathogenic, obligate parasites infecting both vertebrates and invertebrates, exploiting either one (monoxenous) or two hosts (heteroxenous) to complete a full reproductive life cycle. Their pathogenicity varies considerably between species and/or their hosts but as most species are obligate, intracellular parasites they cause some level of pathology in all cases. In relation to abnormal mortality events experienced in scallop populations in the North Atlantic, four different species of scallops, i.e. Iceland scallop, queen scallop, king scallop and sea scallop, were examined for infectious agents, with the aim of shedding light on these events. Most emphasis was made on the Iceland scallop stock in Icelandic waters that unexpectedly collapsed during the 2000s. Its health status was annually monitored for 14 years. In addition to the scallops, whelks and other mollusc species were examined at later stages in the study, in context with presumable life cycle of a pathogen observed. Two different apicomplexan species, both of which appeared to be previously unknown, were identified: 1) Margolisiella islandica, a novel species infecting the heart auricles and highly prevalent in Iceland scallop, without causing any significant pathology, but absent in the three other scallop species. It is a monoxenous species, with all life stages present in a single host, i.e. the Iceland scallop. 2) Initially anonymous species, infecting muscular- and connective tissues, was found in all four scallop species examined. Except for scallops from the UK, infections were generally heavy, causing severe histopathological changes leading to significant reduction in the general condition of the scallops, especially adductor muscles, which become abnormally reduced and discoloured. Furthermore, it hampers normal gonad development, at least in the Iceland scallop. Molecular studies and in situ hybridization, revealed that it is conspecific with Merocystis kathae, an apicomplexan ... |
author2 |
Líf- og umhverfisvísindadeild (HÍ) Faculty of Life and Environmental Sciences (UI) Verkfræði- og náttúruvísindasvið (HÍ) School of Engineering and Natural Sciences (UI) Háskóli Íslands University of Iceland |
format |
Doctoral or Postdoctoral Thesis |
author |
Kristmundsson, Árni |
author_facet |
Kristmundsson, Árni |
author_sort |
Kristmundsson, Árni |
title |
The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean |
title_short |
The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean |
title_full |
The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean |
title_fullStr |
The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean |
title_full_unstemmed |
The nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (Bivalvia; Pectinidae) populations in the North Atlantic Ocean |
title_sort |
nature and pathogenicity of apicomplexan parasites associated with mass mortality events in scallop (bivalvia; pectinidae) populations in the north atlantic ocean |
publisher |
University of Iceland, School of Engineering and Natural Sciences, Faculty of Life and Environmental Sciences |
publishDate |
2018 |
url |
https://hdl.handle.net/20.500.11815/985 |
genre |
Iceland North Atlantic |
genre_facet |
Iceland North Atlantic |
op_relation |
Árni Kristmundsson, 2018, The nature and pathogenicity of apicomplexans infecting scallop (Bivalvia: Pectinidae) populations in the North-Atlantic Ocean, PhD dissertation, Faculty of Life and Environmental Sciences, School of Engineering and Natural Sciences, University of Iceland 978-9935-9438-2-8 https://hdl.handle.net/20.500.11815/985 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/20.500.11815/985 |
_version_ |
1766036691258179584 |