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Tsung-han Lee - One of the best experts on this subject based on the ideXlab platform.
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The ultrastructural characterization of mitochondria-rich cells as a response to variations in salinity in two types of teleostean Pseudobranch: milkfish (Chanos chanos) and Mozambique tilapia (Oreochromis mossambicus)
Journal of morphology, 2017Co-Authors: Sheng-hui Yang, Chao-kai Kang, Hsiu-ni Kung, Jeng Dau Tsai, Wen Kai Yang, Tsung-han LeeAbstract:The Pseudobranchs of two euryhaline teleost species, the milkfish (Chanos chanos) and the Mozambique tilapia (Oreochromis mossambicus), were studied after acclimization to different salinities using optical and electron microscopy. The milkfish Pseudobranch was the lamellae-free type, with separate lamellae along the filaments containing two groups of mitochondria (Mt)-rich cells: chloride cells (CCs) and Pseudobranch type cells (PSCs). Conversely, the tilapia Pseudobranch was the embedded type, covered with connective tissues and with only one group of Mt-rich PSCs. Chloride cells were identified according to the apical openings and branched tubular networks around randomly distributed and diversely shaped Mt. Pseudobranchs type cells, however, were characterized according to the orderly arrangement of parallel tubules around closely packed Mt; both the tubules and the Mt were distributed in the vascular side of the cell, but were absent from the apical region. Compared with those of seawater (SW)-acclimated milkfish, the Pseudobranchial lamellae of freshwater (FW) specimens were longer on average, and the Mt of the CCs had fewer cristae, were less electron-dense, and were often vacuolated. The Mt in the PSCs of FW-acclimated milkfish and tilapia were larger and more electron-dense than those of their SW-acclimated counterparts; in addition, more tubules were found to aggregately surround the Mt and basolateral membranes in the PSCs of fish from the hypo-osmotic environment. Conversely, the PSCs of tilapia were periodic acid-Schiff (PAS)-positive, and Mt in PSCs were concentrated with more parallel arrays of the tubule system than those of milkfish. Therefore, salinity-dependent changes in the ultrastructures of PSCs suggest their potential role in energy metabolism of both lamellae-free and embedded Pseudobranchs, whereas the PAS-positive staining characteristics suggest a role in releasing or storaging polysaccharides in the embedded Pseudobranch. J. Morphol. 278:390-402, 2017. © 2017 Wiley Periodicals, Inc.
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the lamellae free type Pseudobranch of the euryhaline milkfish chanos chanos is a na k atpase abundant organ involved in hypoosmoregulation
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2014Co-Authors: Sheng-hui Yang, Chao-kai Kang, Hsiu-ni Kung, Tsung-han LeeAbstract:article i nfo -ATPase (NKA) activity and protein abundance profiles showed that these parame- ters were higher in the Pseudobranchs of the seawater (SW)- than the freshwater (FW)-acclimated milkfish, op- posite the situation in the gills. The Pseudobranch of the milkfish contained two types of NKA-immunoreactive cells, chloride cells (CCs) and Pseudobranch-type cells (PSCs). To further clarify the roles of CCs and PSCs in the Pseudobranch, we investigated the distributions of two ion transporters: the Na
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The lamellae-free-type Pseudobranch of the euryhaline milkfish (Chanos chanos) is a Na(+), K(+)-ATPase-abundant organ involved in hypoosmoregulation.
Comparative biochemistry and physiology. Part A Molecular & integrative physiology, 2013Co-Authors: Sheng-hui Yang, Chao-kai Kang, Hsiu-ni Kung, Tsung-han LeeAbstract:article i nfo -ATPase (NKA) activity and protein abundance profiles showed that these parame- ters were higher in the Pseudobranchs of the seawater (SW)- than the freshwater (FW)-acclimated milkfish, op- posite the situation in the gills. The Pseudobranch of the milkfish contained two types of NKA-immunoreactive cells, chloride cells (CCs) and Pseudobranch-type cells (PSCs). To further clarify the roles of CCs and PSCs in the Pseudobranch, we investigated the distributions of two ion transporters: the Na
Sheng-hui Yang - One of the best experts on this subject based on the ideXlab platform.
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The ultrastructural characterization of mitochondria-rich cells as a response to variations in salinity in two types of teleostean Pseudobranch: milkfish (Chanos chanos) and Mozambique tilapia (Oreochromis mossambicus)
Journal of morphology, 2017Co-Authors: Sheng-hui Yang, Chao-kai Kang, Hsiu-ni Kung, Jeng Dau Tsai, Wen Kai Yang, Tsung-han LeeAbstract:The Pseudobranchs of two euryhaline teleost species, the milkfish (Chanos chanos) and the Mozambique tilapia (Oreochromis mossambicus), were studied after acclimization to different salinities using optical and electron microscopy. The milkfish Pseudobranch was the lamellae-free type, with separate lamellae along the filaments containing two groups of mitochondria (Mt)-rich cells: chloride cells (CCs) and Pseudobranch type cells (PSCs). Conversely, the tilapia Pseudobranch was the embedded type, covered with connective tissues and with only one group of Mt-rich PSCs. Chloride cells were identified according to the apical openings and branched tubular networks around randomly distributed and diversely shaped Mt. Pseudobranchs type cells, however, were characterized according to the orderly arrangement of parallel tubules around closely packed Mt; both the tubules and the Mt were distributed in the vascular side of the cell, but were absent from the apical region. Compared with those of seawater (SW)-acclimated milkfish, the Pseudobranchial lamellae of freshwater (FW) specimens were longer on average, and the Mt of the CCs had fewer cristae, were less electron-dense, and were often vacuolated. The Mt in the PSCs of FW-acclimated milkfish and tilapia were larger and more electron-dense than those of their SW-acclimated counterparts; in addition, more tubules were found to aggregately surround the Mt and basolateral membranes in the PSCs of fish from the hypo-osmotic environment. Conversely, the PSCs of tilapia were periodic acid-Schiff (PAS)-positive, and Mt in PSCs were concentrated with more parallel arrays of the tubule system than those of milkfish. Therefore, salinity-dependent changes in the ultrastructures of PSCs suggest their potential role in energy metabolism of both lamellae-free and embedded Pseudobranchs, whereas the PAS-positive staining characteristics suggest a role in releasing or storaging polysaccharides in the embedded Pseudobranch. J. Morphol. 278:390-402, 2017. © 2017 Wiley Periodicals, Inc.
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Comparisons of two types of teleostean Pseudobranchs, silver moony (Monodactylus argenteus) and tilapia (Oreochromis mossambicus), with salinity-dependent morphology and ion transporter expression
Journal of Comparative Physiology B, 2015Co-Authors: Sheng-hui Yang, Chao-kai Kang, Shu-chuan Tsai, Yau-chung Hu, Yueh-ling HsiehAbstract:There are essentially four different morphological types of Pseudobranchs in teleosts, including lamellae-free, lamellae semi-free, covered, and embedded types. In the euryhaline silver moony ( Monodactylus argenteus ), the Pseudobranch belongs to the lamellae semi-free type, which is characterized by one row of filaments on the opercular membrane and fusion on the buccal edge. The Pseudobranchial epithelium of the moony contains two types of Na^+, K^+-ATPase (NKA)-rich cells: chloride cells (CCs) and Pseudobranch-type cells (PSCs). Our results revealed increased expression of NKA, the Na^+, K^+, 2Cl^− cotransporter (NKCC), and the cystic fibrosis transmembrane conductance regulator (CFTR) for Cl^− secretion and CCs profiles in the Pseudobranchs of seawater (SW)-acclimated silver moonies, which indicates the potential role of Pseudobranchs containing CCs in hypo-osmoregulation. In contrast, the Pseudobranch of the Mozambique tilapia ( Oreochromis mossambicus ) belongs to the embedded type, which is covered by the connective tissues and only contains PSCs but not CCs. No sign of NKCC and CFTR-immunoreactivity (IR) was found in the Pseudobranchs of SW and freshwater (FW) tilapia. However, higher NKA protein expression and larger sizes of NKA-IR PSCs were found in the Pseudobranchs of FW-acclimated tilapia. Moreover, in the FW-acclimated moony, NKA-IR PSCs also exhibited higher numbers and larger sizes than in the SW individuals. Taken together, similar responses in low-salinity environments in different types of Pseudobranchs indicated that the salinity-dependent morphologies of PSCs might be involved in critical functions for FW teleosts.
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the lamellae free type Pseudobranch of the euryhaline milkfish chanos chanos is a na k atpase abundant organ involved in hypoosmoregulation
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2014Co-Authors: Sheng-hui Yang, Chao-kai Kang, Hsiu-ni Kung, Tsung-han LeeAbstract:article i nfo -ATPase (NKA) activity and protein abundance profiles showed that these parame- ters were higher in the Pseudobranchs of the seawater (SW)- than the freshwater (FW)-acclimated milkfish, op- posite the situation in the gills. The Pseudobranch of the milkfish contained two types of NKA-immunoreactive cells, chloride cells (CCs) and Pseudobranch-type cells (PSCs). To further clarify the roles of CCs and PSCs in the Pseudobranch, we investigated the distributions of two ion transporters: the Na
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The lamellae-free-type Pseudobranch of the euryhaline milkfish (Chanos chanos) is a Na(+), K(+)-ATPase-abundant organ involved in hypoosmoregulation.
Comparative biochemistry and physiology. Part A Molecular & integrative physiology, 2013Co-Authors: Sheng-hui Yang, Chao-kai Kang, Hsiu-ni Kung, Tsung-han LeeAbstract:article i nfo -ATPase (NKA) activity and protein abundance profiles showed that these parame- ters were higher in the Pseudobranchs of the seawater (SW)- than the freshwater (FW)-acclimated milkfish, op- posite the situation in the gills. The Pseudobranch of the milkfish contained two types of NKA-immunoreactive cells, chloride cells (CCs) and Pseudobranch-type cells (PSCs). To further clarify the roles of CCs and PSCs in the Pseudobranch, we investigated the distributions of two ion transporters: the Na
Egil Karlsbakk - One of the best experts on this subject based on the ideXlab platform.
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Infection dynamics and tissue tropism of Parvicapsula Pseudobranchicola (Myxozoa: Myxosporea) in farmed Atlantic salmon (Salmo salar)
Parasites & Vectors, 2018Co-Authors: Are Nylund, Øyvind J. Brevik, Håvard Hustoft, Troels Markussen, Haakon Hansen, Heidrun Plarre, Egil KarlsbakkAbstract:BackgroundThe myxosporean parasite Parvicapsula Pseudobranchicola commonly infects farmed Atlantic salmon in northern Norway. Heavy infections are associated with Pseudobranch lesions, runting and mortality in the salmon populations. The life-cycle of the parasite is unknown, preventing controlled challenge experiments. The infection dynamics, duration of sporogony, tissue tropism and ability to develop immunity to the parasite in farmed Atlantic salmon is poorly known. We conducted a field experiment, aiming at examining these aspects.MethodsInfections in a group of Atlantic salmon were followed from before sea-transfer to the end of the production (604 days). Samples from a range of tissues/sites were analysed using real-time RT-PCR and histology, including in situ hybridization.ResultsAll salmon in the studied population rapidly became infected with P. Pseudobranchicola after sea-transfer medio August. Parasite densities in the Pseudobranchs peaked in winter (November-January), and decreased markedly to March. Densities thereafter decreased further. Parasite densities in other tissues were low. Parasite stages were initially found to be intravascular in the Pseudobranch, but occurred extravascular in the Pseudobranch tissue at 3 months post-sea-transfer. Mature spores appeared in the Pseudobranchs in the period with high parasite densities in the winter (late November-January), and were released (i.e. disappeared from the fish) in the period January-March. Clinical signs of parvicapsulosis (December-early February) were associated with high parasite densities and inflammation in the Pseudobranchs. No evidence for reinfection was seen the second autumn in sea.ConclusionsThe main site of the parasite in Atlantic salmon is the Pseudobranchs. Blood stages occur, but parasite proliferation is primarily associated with extravascular stages in the Pseudobranchs. Disease and mortality (parvicapsulosis) coincide with the completion of sporogony. Atlantic salmon appears to develop immunity to P. Pseudobranchicola. Further studies should focus on the unknown life-cycle of the parasite, and the pathophysiological effects of the Pseudobranch infection that also could affect the eyes and vision.
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infection dynamics and tissue tropism of parvicapsula Pseudobranchicola myxozoa myxosporea in farmed atlantic salmon salmo salar
Parasites & Vectors, 2018Co-Authors: Are Nylund, Øyvind J. Brevik, Håvard Hustoft, Troels Markussen, Haakon Hansen, Heidrun Plarre, Egil KarlsbakkAbstract:The myxosporean parasite Parvicapsula Pseudobranchicola commonly infects farmed Atlantic salmon in northern Norway. Heavy infections are associated with Pseudobranch lesions, runting and mortality in the salmon populations. The life-cycle of the parasite is unknown, preventing controlled challenge experiments. The infection dynamics, duration of sporogony, tissue tropism and ability to develop immunity to the parasite in farmed Atlantic salmon is poorly known. We conducted a field experiment, aiming at examining these aspects. Infections in a group of Atlantic salmon were followed from before sea-transfer to the end of the production (604 days). Samples from a range of tissues/sites were analysed using real-time RT-PCR and histology, including in situ hybridization. All salmon in the studied population rapidly became infected with P. Pseudobranchicola after sea-transfer medio August. Parasite densities in the Pseudobranchs peaked in winter (November-January), and decreased markedly to March. Densities thereafter decreased further. Parasite densities in other tissues were low. Parasite stages were initially found to be intravascular in the Pseudobranch, but occurred extravascular in the Pseudobranch tissue at 3 months post-sea-transfer. Mature spores appeared in the Pseudobranchs in the period with high parasite densities in the winter (late November-January), and were released (i.e. disappeared from the fish) in the period January-March. Clinical signs of parvicapsulosis (December-early February) were associated with high parasite densities and inflammation in the Pseudobranchs. No evidence for reinfection was seen the second autumn in sea. The main site of the parasite in Atlantic salmon is the Pseudobranchs. Blood stages occur, but parasite proliferation is primarily associated with extravascular stages in the Pseudobranchs. Disease and mortality (parvicapsulosis) coincide with the completion of sporogony. Atlantic salmon appears to develop immunity to P. Pseudobranchicola. Further studies should focus on the unknown life-cycle of the parasite, and the pathophysiological effects of the Pseudobranch infection that also could affect the eyes and vision.
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Detection of the myxosporean parasite Parvicapsula Pseudobranchicola in Atlantic salmon (Salmo salar L.) using in situ hybridization (ISH)
Parasites & vectors, 2015Co-Authors: Turhan Markussen, Øyvind J. Brevik, Egil Karlsbakk, Are Nylund, Celia Agusti, Haakon HansenAbstract:Parvicapsula Pseudobranchicola is a marine myxosporean parasite infecting farmed Atlantic salmon (Salmo salar). A major site for the parasite is the Pseudobranch, which may be destroyed in heavily infected fish. Parvicapsulosis may be associated with significant mortality, although the main effect of infections seems to be runting. In situ hybridization (ISH) is, in the absence of specific antibodies, the preferred method for the detection of cell- and tissue tropisms of myxozoans in the early phases of infection of the host, and provides information about the possible association between the pathogen and pathology. A positive diagnosis of parvicapsulosis is based on histopathology and PCR. The aim of the present work was to develop a specific, sensitive and robust ISH assay for the detection of P. Pseudobranchicola in tissues. The ISH method was designed to specifically target P. Pseudobranchicola 18S rDNA/rRNA using a locked nucleic acid (LNA) modified oligonucleotide probe. The method was tested on paraffin embedded P. Pseudobranchicola infected Pseudobranchs. The infections were confirmed by light microscopy revealing the presence of typical P. Pseudobranchicola trophozoites and spores, and the presence of parasite was confirmed with real-time RT-PCR. Specific regions stained by ISH overlapped well with the parasitized and degenerated regions in neighbouring HE stained sections. No staining was observed in Pseudobranchs of Atlantic salmon which had been held in P. Pseudobranchicola-free water. We report here the development of a sensitive ISH assay for the detection of P. Pseudobranchicola in paraffin embedded tissue. The technique will be valuable in the study of host entry, early proliferation, pre-spore development, pathology and tissue tropism in Atlantic salmon.
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Parvicapsula Pseudobranchicola (Myxosporea) in farmed Atlantic salmon Salmo salar. Tissue distribution, diagnosis and phylogeny.
Diseases of aquatic organisms, 2005Co-Authors: Are Nylund, Egil Karlsbakk, P. A. Sæther, C. Koren, T. Larsen, B. D. Nielsen, A. E. Brøderud, C. Høstlund, K. R. Fjellsøy, K. LervikAbstract:Parvicapsula Pseudobranchicola infections in farmed Atlantic salmon in Norway are associated with low-grade to significant mortalities. The parasite is found as mature spores in Pseudobranchs, but has also been detected in the gills, liver and kidney. Diagnosis has relied on the detection of Parvicapsula spores, with the Pseudobranch being the preferred organ. A better understanding of the epizootiology of this myxosporean is a prerequisite for appropriate management and control. Hence, early detection of infections and life cycle studies are needed. We sequenced the small subunit (ssu) rDNA (18S) from P. Pseudobranchicola and developed a sensitive diagnostic PCR protocol. This allowed us to (1) identify appropriate tissues for diagnostic assays, (2) examine the intraspecific variation in ssu rDNA in the parasite's Norwegian range, (3) examine annelid potential primary hosts and (4) obtain additional ssu rDNA sequences of marine Parvicapsula species to perform a phylogenetic study. Primers were constructed targeting the ssu rDNA from P. minibicornis. With these we obtained a partial ssu sequence of the P. Pseudobranchicola type isolate. A new set of primers (PCF3/PCR3) was constructed for diagnostic purposes. These were tested against DNA from the host and several myxozoan species infecting Norwegian salmon. The primers give a positive product of 203 bp and pick out P. Pseudobranchicola in salmnonids. They also amplify the congeners P. unicornis and P. asymmetrica infecting unrelated fish. The PCR protocol developed showed a greater sensitivity than light microscopy. The Pseudobranchs were always positive and are the recommended organ for PCR diagnostics. There was no sequence variation between geographic isolates from farmed salmon. Preliminary examinations of marine polychaetes and oligochaetes collected from farm sites with parvicapsulose problems were negative. A comparison of the sequence of the ssu rDNA from P. Pseudobranchicola with that of other myxozoans shows that it groups closely together with P. unicornis and P. asymmetrica. The closest relative to this group is P. minibicornis.
Graham Young - One of the best experts on this subject based on the ideXlab platform.
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Pseudobranch and gill na k atpase activity in juvenile chinook salmon oncorhynchus tshawytscha developmental changes and effects of growth hormone cortisol and seawater transfer
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2003Co-Authors: Michael C.j. Quinn, Philip A. Veillette, Graham YoungAbstract:Abstract The teleost Pseudobranch is a gill-like structure often fused to the anterior of the opercular cavity. Pseudobranch cells are mitochondria rich and have high levels of Na + , K + -ATPase activity. In this study, Pseudobranch Na + , K + -ATPase activity in juvenile chinook salmon ( Oncorhynchus tshawytscha ) was compared to gill Na + , K + -ATPase activity, a known marker of parr–smolt transformation, in three experiments. In two stocks of New Zealand chinook salmon, Pseudobranch Na + , K + -ATPase activity was found to significantly increase during development. At these times gill Na + , K + -ATPase activity was also elevated. Pseudobranch Na + , K + -ATPase activity did not increase 10 days after transfer from fresh water to 34 ppt seawater, a treatment that resulted in a twofold increase in gill Na + , K + -ATPase activity. Cortisol (50 μg/g) and ovine growth hormone (5 μg/g) implants had no effect on Pseudobranch Na + , K + -ATPase activity in underyearling chinook salmon, while gill Na + , K + -ATPase activity was stimulated by each hormone. In yearling chinook salmon, only cortisol stimulated Pseudobranch Na + , K + -ATPase activity 14 days post-implantation. It was concluded that the Pseudobranch differs from the gill in terms of the regulation of Na + , K + -ATPase activity and a role during adaptation to seawater is likely to be limited.
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Pseudobranch and gill Na+, K+-ATPase activity in juvenile chinook salmon, Oncorhynchus tshawytscha: developmental changes and effects of growth hormone, cortisol and seawater transfer
Comparative biochemistry and physiology. Part A Molecular & integrative physiology, 2003Co-Authors: Michael C.j. Quinn, Philip A. Veillette, Graham YoungAbstract:Abstract The teleost Pseudobranch is a gill-like structure often fused to the anterior of the opercular cavity. Pseudobranch cells are mitochondria rich and have high levels of Na + , K + -ATPase activity. In this study, Pseudobranch Na + , K + -ATPase activity in juvenile chinook salmon ( Oncorhynchus tshawytscha ) was compared to gill Na + , K + -ATPase activity, a known marker of parr–smolt transformation, in three experiments. In two stocks of New Zealand chinook salmon, Pseudobranch Na + , K + -ATPase activity was found to significantly increase during development. At these times gill Na + , K + -ATPase activity was also elevated. Pseudobranch Na + , K + -ATPase activity did not increase 10 days after transfer from fresh water to 34 ppt seawater, a treatment that resulted in a twofold increase in gill Na + , K + -ATPase activity. Cortisol (50 μg/g) and ovine growth hormone (5 μg/g) implants had no effect on Pseudobranch Na + , K + -ATPase activity in underyearling chinook salmon, while gill Na + , K + -ATPase activity was stimulated by each hormone. In yearling chinook salmon, only cortisol stimulated Pseudobranch Na + , K + -ATPase activity 14 days post-implantation. It was concluded that the Pseudobranch differs from the gill in terms of the regulation of Na + , K + -ATPase activity and a role during adaptation to seawater is likely to be limited.
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salmon, Oncorhynchus tshawytscha: developmental changes and effects of growth hormone, cortisol and seawater transfer
2003Co-Authors: Michael C.j. Quinn, Philip A. Veillette, Graham YoungAbstract:b Abstract The teleost Pseudobranch is a gill-like structure often fused to the anterior of the opercular cavity. Pseudobranch cells are mitochondria rich and have high levels of Na , K -ATPase activity. In this study, Pseudobranch Na , K -ATPase qq q q
Jan Thulin - One of the best experts on this subject based on the ideXlab platform.
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Pseudanthocotyloides heterocotyle (van Beneden, 1871) Euzet & Prost, 1969 (Monogenea: Polyopisthocotylea: Mazocraeidae), a parasite of herring Clupea harengus L. and sprat Sprattus sprattus L. (Teleostei: Clupeidae)
Systematic Parasitology, 1999Co-Authors: Hassan Rahimian, Matt Longshaw, Ken Mackenzie, Jan ThulinAbstract:A total of 690 herring Clupea harengus L. and 88 sprat Sprattus sprattus L. caught off the west coast of Sweden, in the North Sea and off the west and south coasts of the United Kingdom, were examined for gill parasites. The monogenean Pseudanthocotyloides heterocotyle (van Beneden, 1871) Euzet & Prost, 1969 was found in 38 (5.5%) herring and one (1.1%) sprat. The parasite was significantly (P>0.05) more common off the west coast of Sweden than elsewhere and most specimens (62.5%) were found on the Pseudobranchs. Only the smaller herring were infected. P. heterocotyle is redescribed and its taxonomy discussed, together with the possibility of host and parasite misidentification in previous reports.
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Pseudanthocotyloides heterocotyle (van Beneden, 1871) Euzet & Prost, 1969 (Monogenea: Polyopisthocotylea: Mazocraeidae), a parasite of herring Clupea harengus L. and sprat Sprattus sprattus L. (Teleostei: Clupeidae)
Systematic Parasitology, 1999Co-Authors: Hassan Rahimian, Matt Longshaw, Ken Mackenzie, Jan ThulinAbstract:A total of 690 herring Clupea harengus L. and 88 sprat Sprattus sprattus L. caught off the west coast of Sweden, in the North Sea and off the west and south coasts of the United Kingdom, were examined for gill parasites. The monogenean Pseudanthocotyloides heterocotyle (van Beneden, 1871) Euzet & Prost, 1969 was found in 38 (5.5%) herring and one (1.1%) sprat. The parasite was significantly (P>0.05) more common off the west coast of Sweden than elsewhere and most specimens (62.5%) were found on the Pseudobranchs. Only the smaller herring were infected. P. heterocotyle is redescribed and its taxonomy discussed, together with the possibility of host and parasite misidentification in previous reports.
