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Marianne Koie - One of the best experts on this subject based on the ideXlab platform.
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a parvicapsulid myxozoa infecting sprattus sprattus and clupea harengus Clupeidae in the northeast atlantic uses hydroides norvegicus serpulidae as invertebrate host
Folia Parasitologica, 2013Co-Authors: Marianne Koie, Egil Karlsbakk, Anncathrine Bardsgjaere Einen, Are NylundAbstract:Abstract: A myxosporean producing actinospores of the tetractinomyxon type in Hydroides norvegicus Gunnerus (Serpulidae) in Denmark was identified as a member of the family Parvicapsulidae based on small-subunit ribosomal DNA (SSU rDNA) sequences. Myxosporean samples from various Danish and Norwegian marine fishes were examined with primers that detect the novel myxosporean. Sprattus sprattus (Linnaeus) and Clupea harengus Linnaeus (Teleostei, Clupeidae) were found to be infected. The sequences of this parvicapsulid from these hosts were consistently slightly different (0.8% divergence), but both these genotypes were found in H. norvegicus. Disporic trophozoites and minute spores of a novel myxosporean type were observed in the renal tubules of some of the hosts found infected through PCR. The spores appear most similar to those of species of Gadimyxa Koie, Karlsbakk et Nylund, 2007, but are much smaller. The actinospores of the tetractinomyxon type from H. norvegicus have been described previously. In GenBank, the SSU rDNA sequences of Parvicapsulidae gen. sp. show highest identity (82%) with Parvicapsula minibicornis Kent, Whitaker et Dawe, 1997 infecting salmonids (Oncorhynchus spp.) in fresh water in the western North America. A phylogenetic analysis places P. minibicornis and Parvicapsulidae gen. sp. in a sister clade to the other parvicapsulids (Parvicapsula spp. and Gadimyxa spp.).
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morphology and ssu rdna sequences of ortholinea orientalis shul man and shul man albova 1953 myxozoa ortholineidae from clupea harengus and sprattus sprattus Clupeidae from denmark
Parasitology Research, 2011Co-Authors: Egil Karlsbakk, Marianne KoieAbstract:Ortholinea orientalis (Shul’man and Shul’man-Albova 1953) Shul’man 1956 is redescribed from Clupea harengus L. and Sprattus sprattus (L.) (Teleostei, Clupeidae) from the northern Oresund, Denmark. S. sprattus is a new host record. Polysporic plasmodia and most myxospores were found in the ureters of both hosts. The myxospores have external valvular ridges, which were not observed in the original description. The presence of this character causes us to consider Ortholinea Clupeidae Aseeva 2000 as a likely synonym of O. orientalis. Ortholinea antipae Moshu and Trombitsky, 2006 from a Black Sea clupeid is also similar and represent a possible synonym. Sequence comparisons and phylogenetic analysis of partial SSU rDNA sequences of O. orientalis reveal closest affinity (82–86% identity) to members of the ‘Freshwater Urinary Bladder Clade’ sensu Fiala (2006), a clade among the Platysporina containing members of the myxosporean genera Myxobilatus, Hoferellus, Myxidium, Zschokkella and Chloromyxum from freshwater fishes.
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Morphology and SSU rDNA sequences of Ortholinea orientalis (Shul’man and Shul’man-Albova, 1953) (Myxozoa, Ortholineidae) from Clupea harengus and Sprattus sprattus (Clupeidae) from Denmark
Parasitology Research, 2011Co-Authors: Egil Karlsbakk, Marianne KoieAbstract:Ortholinea orientalis (Shul’man and Shul’man-Albova 1953) Shul’man 1956 is redescribed from Clupea harengus L. and Sprattus sprattus (L.) (Teleostei, Clupeidae) from the northern Oresund, Denmark. S. sprattus is a new host record. Polysporic plasmodia and most myxospores were found in the ureters of both hosts. The myxospores have external valvular ridges, which were not observed in the original description. The presence of this character causes us to consider Ortholinea Clupeidae Aseeva 2000 as a likely synonym of O. orientalis. Ortholinea antipae Moshu and Trombitsky, 2006 from a Black Sea clupeid is also similar and represent a possible synonym. Sequence comparisons and phylogenetic analysis of partial SSU rDNA sequences of O. orientalis reveal closest affinity (82–86% identity) to members of the ‘Freshwater Urinary Bladder Clade’ sensu Fiala (2006), a clade among the Platysporina containing members of the myxosporean genera Myxobilatus, Hoferellus, Myxidium, Zschokkella and Chloromyxum from freshwater fishes.
Michael J Jech - One of the best experts on this subject based on the ideXlab platform.
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in situ acoustic estimates of the swimbladder volume of atlantic herring clupea harengus
Ices Journal of Marine Science, 2004Co-Authors: Redwood W. Nero, Charles H. Thompson, Michael J JechAbstract:Acoustic measurements at 1.5-5 kHz on fish in the Gulf of Maine showed a swimbladder-resonance peak near 2.5 kHz at 160-190-m depth. Midwater trawls confirmed that the fish were likely to be Atlantic herring (Clupea harengus) of 19-29 cm length. Calculation using a model of swimbladder resonance gives swimbladder volumes of 1.2% of fish weight at 160-190 m. Extrapolation of this volume of gas using Boyle's Law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to five to six times the volume required for neutral buoyancy. If these fish were to maintain this volume of gas with surface “gulping”, they would need to submerge from the sea surface with a 30% excess buoyancy. In general, swimbladders of the Clupeidae may have greater volumes of gas than if the fish were neutrally buoyant at the sea surface and the interpretation of HF-echosounder surveys may be additionally complex when the volume of gas and swimbladder volume are difficult to predict. Mechanisms of how herring obtain additional swimbladder gas are discussed.
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in situ acoustic estimates of the swimbladder volume of atlantic herring clupea harengus
Journal of the Acoustical Society of America, 2002Co-Authors: Redwood W. Nero, Charles H. Thompson, Michael J JechAbstract:Most marine fish maintain swimbladder volumes equivalent to 4%–5% of their body weight in order to maintain neutral buoyancy. In many fish the addition or removal of gas from the swimbladder is accomplished with the gas gland, a blood invested portion of the swimbladder wall. However, several families, including the herring family, Clupeidae, lack a gas gland. Instead, these fish possess a pneumatic duct between the esophagus and the swimbladder by which they are believed to inflate their swimbladders by ‘‘gulping’’ atmospheric air at the sea surface. Acoustic measurements at 1.5–5 kHz on fish in the Gulf of Maine showed a swimbladder resonance peak near 2.3 kHz at 180 m depth. Midwater trawls confirmed that the fish were Atlantic herring (Clupea harengus) of 19–28 cm length. Calculations using a model of swimbladder resonance gives swimbladder volumes of 1.3% at 180 m. Extrapolation using Boyle’s law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to four ti...
Egil Karlsbakk - One of the best experts on this subject based on the ideXlab platform.
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a parvicapsulid myxozoa infecting sprattus sprattus and clupea harengus Clupeidae in the northeast atlantic uses hydroides norvegicus serpulidae as invertebrate host
Folia Parasitologica, 2013Co-Authors: Marianne Koie, Egil Karlsbakk, Anncathrine Bardsgjaere Einen, Are NylundAbstract:Abstract: A myxosporean producing actinospores of the tetractinomyxon type in Hydroides norvegicus Gunnerus (Serpulidae) in Denmark was identified as a member of the family Parvicapsulidae based on small-subunit ribosomal DNA (SSU rDNA) sequences. Myxosporean samples from various Danish and Norwegian marine fishes were examined with primers that detect the novel myxosporean. Sprattus sprattus (Linnaeus) and Clupea harengus Linnaeus (Teleostei, Clupeidae) were found to be infected. The sequences of this parvicapsulid from these hosts were consistently slightly different (0.8% divergence), but both these genotypes were found in H. norvegicus. Disporic trophozoites and minute spores of a novel myxosporean type were observed in the renal tubules of some of the hosts found infected through PCR. The spores appear most similar to those of species of Gadimyxa Koie, Karlsbakk et Nylund, 2007, but are much smaller. The actinospores of the tetractinomyxon type from H. norvegicus have been described previously. In GenBank, the SSU rDNA sequences of Parvicapsulidae gen. sp. show highest identity (82%) with Parvicapsula minibicornis Kent, Whitaker et Dawe, 1997 infecting salmonids (Oncorhynchus spp.) in fresh water in the western North America. A phylogenetic analysis places P. minibicornis and Parvicapsulidae gen. sp. in a sister clade to the other parvicapsulids (Parvicapsula spp. and Gadimyxa spp.).
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morphology and ssu rdna sequences of ortholinea orientalis shul man and shul man albova 1953 myxozoa ortholineidae from clupea harengus and sprattus sprattus Clupeidae from denmark
Parasitology Research, 2011Co-Authors: Egil Karlsbakk, Marianne KoieAbstract:Ortholinea orientalis (Shul’man and Shul’man-Albova 1953) Shul’man 1956 is redescribed from Clupea harengus L. and Sprattus sprattus (L.) (Teleostei, Clupeidae) from the northern Oresund, Denmark. S. sprattus is a new host record. Polysporic plasmodia and most myxospores were found in the ureters of both hosts. The myxospores have external valvular ridges, which were not observed in the original description. The presence of this character causes us to consider Ortholinea Clupeidae Aseeva 2000 as a likely synonym of O. orientalis. Ortholinea antipae Moshu and Trombitsky, 2006 from a Black Sea clupeid is also similar and represent a possible synonym. Sequence comparisons and phylogenetic analysis of partial SSU rDNA sequences of O. orientalis reveal closest affinity (82–86% identity) to members of the ‘Freshwater Urinary Bladder Clade’ sensu Fiala (2006), a clade among the Platysporina containing members of the myxosporean genera Myxobilatus, Hoferellus, Myxidium, Zschokkella and Chloromyxum from freshwater fishes.
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Morphology and SSU rDNA sequences of Ortholinea orientalis (Shul’man and Shul’man-Albova, 1953) (Myxozoa, Ortholineidae) from Clupea harengus and Sprattus sprattus (Clupeidae) from Denmark
Parasitology Research, 2011Co-Authors: Egil Karlsbakk, Marianne KoieAbstract:Ortholinea orientalis (Shul’man and Shul’man-Albova 1953) Shul’man 1956 is redescribed from Clupea harengus L. and Sprattus sprattus (L.) (Teleostei, Clupeidae) from the northern Oresund, Denmark. S. sprattus is a new host record. Polysporic plasmodia and most myxospores were found in the ureters of both hosts. The myxospores have external valvular ridges, which were not observed in the original description. The presence of this character causes us to consider Ortholinea Clupeidae Aseeva 2000 as a likely synonym of O. orientalis. Ortholinea antipae Moshu and Trombitsky, 2006 from a Black Sea clupeid is also similar and represent a possible synonym. Sequence comparisons and phylogenetic analysis of partial SSU rDNA sequences of O. orientalis reveal closest affinity (82–86% identity) to members of the ‘Freshwater Urinary Bladder Clade’ sensu Fiala (2006), a clade among the Platysporina containing members of the myxosporean genera Myxobilatus, Hoferellus, Myxidium, Zschokkella and Chloromyxum from freshwater fishes.
Redwood W. Nero - One of the best experts on this subject based on the ideXlab platform.
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in situ acoustic estimates of the swimbladder volume of atlantic herring clupea harengus
Ices Journal of Marine Science, 2004Co-Authors: Redwood W. Nero, Charles H. Thompson, Michael J JechAbstract:Acoustic measurements at 1.5-5 kHz on fish in the Gulf of Maine showed a swimbladder-resonance peak near 2.5 kHz at 160-190-m depth. Midwater trawls confirmed that the fish were likely to be Atlantic herring (Clupea harengus) of 19-29 cm length. Calculation using a model of swimbladder resonance gives swimbladder volumes of 1.2% of fish weight at 160-190 m. Extrapolation of this volume of gas using Boyle's Law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to five to six times the volume required for neutral buoyancy. If these fish were to maintain this volume of gas with surface “gulping”, they would need to submerge from the sea surface with a 30% excess buoyancy. In general, swimbladders of the Clupeidae may have greater volumes of gas than if the fish were neutrally buoyant at the sea surface and the interpretation of HF-echosounder surveys may be additionally complex when the volume of gas and swimbladder volume are difficult to predict. Mechanisms of how herring obtain additional swimbladder gas are discussed.
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in situ acoustic estimates of the swimbladder volume of atlantic herring clupea harengus
Journal of the Acoustical Society of America, 2002Co-Authors: Redwood W. Nero, Charles H. Thompson, Michael J JechAbstract:Most marine fish maintain swimbladder volumes equivalent to 4%–5% of their body weight in order to maintain neutral buoyancy. In many fish the addition or removal of gas from the swimbladder is accomplished with the gas gland, a blood invested portion of the swimbladder wall. However, several families, including the herring family, Clupeidae, lack a gas gland. Instead, these fish possess a pneumatic duct between the esophagus and the swimbladder by which they are believed to inflate their swimbladders by ‘‘gulping’’ atmospheric air at the sea surface. Acoustic measurements at 1.5–5 kHz on fish in the Gulf of Maine showed a swimbladder resonance peak near 2.3 kHz at 180 m depth. Midwater trawls confirmed that the fish were Atlantic herring (Clupea harengus) of 19–28 cm length. Calculations using a model of swimbladder resonance gives swimbladder volumes of 1.3% at 180 m. Extrapolation using Boyle’s law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to four ti...
Veronica Gutierrez - One of the best experts on this subject based on the ideXlab platform.
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phylogeography of the southwestern atlantic menhaden genus brevoortia Clupeidae alosinae
Marine Biology, 2008Co-Authors: Graciela Garcia, Julia Vergara, Veronica GutierrezAbstract:Among pelagic fish, the Southwestern Atlantic menhaden genus Brevoortia (Clupeidae, Alosinae) constitutes an important species model to investigate the patterns of genetic differentiation. It is abundant in the Rio de la Plata estuary and in the Atlantic coastal lagoons system from Uruguay and Southern Brazil. To access in the taxa discrimination and population structure in Brevoortia we perform a phylogeographic approach based on mitochondrial cytochrome b (cyt-b) sequences including 240 individuals from 16 collecting sites. Among the 720 bp cyt-b sequenced, 199 correspond to variables and 88 to phylogenetically informative sites. High values of haplotype diversity (h = 1.000) and nucleotide diversity (π = 0.061), as well as an average of 0.084 polymorphic segregating sites and 46 different haplotypes were found. Maximum likelihood analysis based on the GTR + I + G model and Bayesian inference strongly support the idea that B. aurea is the only species of the genus inhabiting the Southwestern Atlantic region. Our analyses revealed a complex population pattern characterized by the existence of long-term highly structured genetic assemblages of mixed stocks. Each monophyletic entity included individuals from different collecting sites, different age groups and collected in different years. Our data also suggest that the recruitment of unrelated mtDNA haplotypes carried out by individuals within schools could be occurring in the same nursery areas revealing the existence of many different maternal lineages. A scenario where different simultaneously and successively mixed mtDNA lineages remain historically connected through basal haplotypes among different clades could explains more accurately the complex and ordered metapopulation dynamic found in this pelagic fish.