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Costas Triantaphyllidis - One of the best experts on this subject based on the ideXlab platform.
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Shallow genetic structure of three species of the genus Trachurus in European waters
Marine Ecology Progress Series, 2004Co-Authors: Nikoletta Karaiskou, Alexander Triantafyllidis, Costas TriantaphyllidisAbstract:Pelagic marine fishes generally show little geographical population differentiation. Of special interest are marine species with Atlantic-Mediterranean distribution because of the possible effect of past and present day restrictions to gene flow between the 2 seas. Thus, restriction analysis of the whole control region (D-loop) of mitochondrial DNA (mtDNA) was used to extensively investi- gate the genetic structure of the 3 Trachurus species present both in Atlantic and Mediterranean waters: T. Trachurus, T. mediterraneus and T. picturatus. In total, 666 individuals were screened from 5 Mediterranean and 6 Atlantic areas. Two African areas were also sampled for T. Trachurus. No dif- ferentiation was revealed among European populations within the 3 studied species. Additionally, no sign of Atlantic-Mediterranean division was found, probably due to the fact that specific life history traits provide the Trachurus species with flexibility to oceanographical constraints and give them the ability to migrate long distances. Differentiation was only revealed between European and African populations of T. Trachurus, reinforcing the existence of the T. Trachurus capensis subspecies in African waters. Populations are probably under long and stable demographic equilibrium conditions as indicated by high haplotypic and nucleotide diversity values for all 3 species. Thus, mtDNA could be a powerful tool in determining the taxonomic distinctiveness of individual populations and spe- cies, and therefore, aid in setting priorities for future management policies. The present results are also discussed in comparison with the results of previous cytochrome b sequence analysis of the 3 Trachurus species.
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Discrimination of three Trachurus species using both mitochondrial- and nuclear-based DNA approaches.
Journal of agricultural and food chemistry, 2003Co-Authors: Nikoletta Karaiskou, And Alexander Triantafyllidis, Costas TriantaphyllidisAbstract:A double-DNA approach was developed to discriminate the three Trachurus species that abide in European waters: T. Trachurus, T. mediterraneus, and T. picturatus. The analysis aimed at both mitochondrial and nuclear loci. Polymerase Chain Reaction (PCR) amplification of the cytochrome b gene of mtDNA was followed by restriction analysis with three species-specific enzymes: NlaIII, NciI, and BsmAI. Digestion with these endonucleases yielded species-specific electrophoretic profiles. The universality of the results was verified by screening a large number of individuals from 12 geographical regions covering most of the distribution of the species. Additionally, the nuclear multicopy 5S rRNA gene was selected as an alternative candidate for the discrimination of the three Trachurus species. A simple agarose gel electrophoretic analysis of the amplicons proved to be capable of leading to unambiguous identification of the three Trachurus species. Thus, the double-DNA methodology presented here allows the accura...
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Genetic Identification and Phylogeny of Three Species of the Genus Trachurus Based on Mitochondrial DNA Analysis
Marine Biotechnology, 2003Co-Authors: Nikoletta Karaiskou, Apostolos Apostolidis, Alexandros Triantafyllidis, Anastasia Kouvatsi, Costas TriantaphyllidisAbstract:The genetic identification and the phylogenetic relationships of 3 European species of the genus Trachurus (T. Trachurus, T. mediterraneus, and T. picturatus) across their geographical distribution, have been investigated by mitochondrial DNA analysis. Both cytochrome b and 16S ribosomal DNA sequence analysis revealed the existence of several species-specific positions that distinguish the 3 studied species. Genetic distances between the species indicated that T. mediterraneus and T. picturatus are more closely related than T. Trachurus. Similar topologies have been produced by neighbor-joining, maximum-likelihood, and maximum-parsimony trees, and they were in accordance with previous taxonomic classification. Internucleotide and intranucleotide diversity of T. picturatus was 2 times higher than that of T. mediterraneus and T. Trachurus, possibly owing to the low levels of fishing pressure for T. picturatus. This is the first report of the phylogenetic relationships of the 3 Trachurus species and provides a possible scenario of the time of divergence related to the closure of the Gibraltar Straits. In addition, the present results can be used for genetic identification of the 3 species, even from the early stage of eggs, and for detection of commercial fraud.
K Mackenzie - One of the best experts on this subject based on the ideXlab platform.
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parasites as biological tags for stock identification of atlantic horse mackerel Trachurus Trachurus l
Fisheries Research, 2008Co-Authors: K Mackenzie, N Campbell, Simonetta Mattiucci, P Ramos, A L Pinto, Pablo AbaunzaAbstract:Abstract Forty-five different parasite taxa were recorded from 1919 Atlantic horse mackerel Trachurus Trachurus caught at 20 stations in a study area from off the coast of Morocco to south-west Norway, and throughout the Mediterranean Sea. Eleven taxa are new host records, and one is probably a new species. The geographical distribution and biology of each parasite and its value for the stock identification of T. Trachurus are described and discussed. The most effective biological tags were the larval nematodes Anisakis spp. and Hysterothylacium aduncum . The distinctive pattern of infection with these nematodes observed in samples from the single North Sea station clearly distinguishes this from all other stations and supports the current management strategy which treats the North Sea population as a separate stock. The distinction between the putative “western”, “southern” and “mauritanian” stocks is less clear, with evidence of considerable mixing between them. The highly localised distributions of some parasites in the Mediterranean part of the study area suggest that T. Trachurus populations there appear to comprise three main stocks—western, central and eastern. There is also strong evidence of the migration of fish from Atlantic populations into the extreme western part of the Mediterranean.
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Parasites as biological tags in population studies of marine organisms: an update
Parasitology, 2002Co-Authors: K MackenzieAbstract:This paper reviews the work published over the past decade on the use of parasites as biological tags in population studies of marine fish, mammals and invertebrates. Fish hosts are considered in taxonomic and ecological groups as follows: demersal, anadromous, small pelagic, large pelagic and elasmobranch. Most studies were carried out on demersal fish, particularly on members of the genera Merluccius (hake), Sebastes (rockfish) and on Atlantic cod Gadus morhua L., but Pacific salmonids and small pelagic fish of the genus Trachurus are also well-represented. A current multidisciplinary study of the population biology of horse mackerel Trachurus Trachurus in European waters, which includes the use of parasites as tags, is described. Two studies recognize the potential for using parasites as tags for cetaceans but, in spite of the considerable potential for this approach in population studies of elasmobranchs, no original study has been carried out on this group for over ten years. Studies of parasites as tags for marine invertebrates have concentrated on squid. Recent trends in the use of parasites as biological tags for marine hosts are discussed.
Pablo Abaunza - One of the best experts on this subject based on the ideXlab platform.
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parasites as biological tags for stock identification of atlantic horse mackerel Trachurus Trachurus l
Fisheries Research, 2008Co-Authors: K Mackenzie, N Campbell, Simonetta Mattiucci, P Ramos, A L Pinto, Pablo AbaunzaAbstract:Abstract Forty-five different parasite taxa were recorded from 1919 Atlantic horse mackerel Trachurus Trachurus caught at 20 stations in a study area from off the coast of Morocco to south-west Norway, and throughout the Mediterranean Sea. Eleven taxa are new host records, and one is probably a new species. The geographical distribution and biology of each parasite and its value for the stock identification of T. Trachurus are described and discussed. The most effective biological tags were the larval nematodes Anisakis spp. and Hysterothylacium aduncum . The distinctive pattern of infection with these nematodes observed in samples from the single North Sea station clearly distinguishes this from all other stations and supports the current management strategy which treats the North Sea population as a separate stock. The distinction between the putative “western”, “southern” and “mauritanian” stocks is less clear, with evidence of considerable mixing between them. The highly localised distributions of some parasites in the Mediterranean part of the study area suggest that T. Trachurus populations there appear to comprise three main stocks—western, central and eastern. There is also strong evidence of the migration of fish from Atlantic populations into the extreme western part of the Mediterranean.
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Environmental variability in the North Atlantic and Iberian waters and its influence on horse mackerel (Trachurus Trachurus) and albacore (Thunnus alalunga) dynamics
ICES Journal of Marine Science, 2007Co-Authors: Alicia Lavín, Pablo Abaunza, Xabier Moreno-ventas, Victoria Ortiz De Zarate, J. M. CabanasAbstract:Lavin, A., Moreno-Ventas, X., Ortiz de Zarate, V., Abaunza, P., and Cabanas, J. M. 2007. Environmental variability in the North Atlantic and Iberian waters and its influence on horse mackerel (Trachurus Trachurus) and albacore (Thunnus alalunga) dynamics. - ICES Journal of Marine Science, 64: 425-438.We explore the potential impact of climatic and oceanic variables on the dynamics of horse mackerel Trachurus Trachurus (coastal distribution) and albacore Thunnus alalunga (oceanic distribution). Principal components analysis of a set of environmental parameters for the years 1966-2000 allowed us to characterize the system by three components. The first consisted mainly of sea surface temperature (SST; 18.5% of variability), the second was determined by the oceanic transport indices, potential energy anomaly (PEA), and the Gulf Stream Index (15.6%), and the third by the meridional wind component and Ekman transport (11.5%). Horse mackerel recruitment was negatively correlated mainly with the first thermal component, whereas albacore age 3 catches were negatively correlated with the second oceanic component and positively with the third wind component. Multiple linear regression confirmed that environmental conditions [SST, PEA, and the zonal (east-west) wind component] explained the availability of age 3 albacore to the surface fisheries for the period 1975-1999. In contrast, cross-validation analysis showed that environmental conditions did not consistently explain horse mackerel recruitment, probably because of the short time-series available (15 y).
E. Olmo - One of the best experts on this subject based on the ideXlab platform.
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Karyotype differentiation between two species of carangid fishes, genusTrachurus (Perciformes: Carangidae)
Marine Biology, 1996Co-Authors: V. Caputo, F. Marchegiani, E. OlmoAbstract:A karyological study of Trachurus Trachurus and T. mediterraneus (Perciformes: Carangidae) was conducted by standard, fluorochrome staining (CMA_3, mithramycin, quinacrine mustard, DAPI), C-, Ag-NOR, and Alu-I banding methods. The karyotypes of both species consisted of 2 n = 48 chromosomes, but of different FN: T. Trachurus possessed a chromosome complement of 2 metacentric and 46 acrocentric elements, fundamental number (FN) = 50 and T. mediterraneus , a chromosome complement of 4 metacentric, 4 submetacentric, 14 subtelocentric and 26 acrocentric chromosomes, FN = 70. In neither of the two taxa investigated were heteromorphic sex chromosomes observed. The nucleolar organizer region was interstitially located on the long arm of the Ist pair of chromosomes in both species, intermediate in T. mediterraneus and subterminal in T. Trachurus . Constitutive heterochromatin was found in nearly all centromeric and telomeric regions in T. Trachurus ; in T. mediterraneus it formed less intense telomeric and centromeric bands and thin interstitial bands on eight chromosome pairs. In addition, the C-positive material reacted differently to the digestion with endonuclease Alu-l in the two species. The results are discussed and compared with karyological data known for other species of Carangidae.
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Karyotype differentiation between two species of carangid fishes, genus Trachurus (Perciformes: Carangidae)
Marine Biology, 1996Co-Authors: V. Caputo, F. Marchegiani, E. OlmoAbstract:A karyological study ofTrachurus Trachurus andT. mediterraneus (Perciformes: Carangidae) was conducted by standard, fluorochrome staining (CMA3, mithramycin, quinacrine mustard, DAPI), C-, Ag-NOR, and Alu-I banding methods. The karyotypes of both species consisted of 2n = 48 chromosomes, but of different FN:T. Trachurus possessed a chromosome complement of 2 metacentric and 46 acrocentric elements, fundamental number (FN) = 50 andT. mediterraneus, a chromosome complement of 4 metacentric, 4 submetacentric, 14 subtelocentric and 26 acrocentric chromosomes, FN = 70. In neither of the two taxa investigated were heteromorphic sex chromosomes observed. The nucleolar organizer region was interstitially located on the long arm of the Ist pair of chromosomes in both species, intermediate inT. mediterraneus and subterminal inT. Trachurus. Constitutive heterochromatin was found in nearly all centromeric and telomeric regions inT. Trachurus; inT. mediterraneus it formed less intense telomeric and centromeric bands and thin interstitial bands on eight chromosome pairs. In addition, the C-positive material reacted differently to the digestion with endonuclease Alu-l in the two species. The results are discussed and compared with karyological data known for other species of Carangidae.
Nikoletta Karaiskou - One of the best experts on this subject based on the ideXlab platform.
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Shallow genetic structure of three species of the genus Trachurus in European waters
Marine Ecology Progress Series, 2004Co-Authors: Nikoletta Karaiskou, Alexander Triantafyllidis, Costas TriantaphyllidisAbstract:Pelagic marine fishes generally show little geographical population differentiation. Of special interest are marine species with Atlantic-Mediterranean distribution because of the possible effect of past and present day restrictions to gene flow between the 2 seas. Thus, restriction analysis of the whole control region (D-loop) of mitochondrial DNA (mtDNA) was used to extensively investi- gate the genetic structure of the 3 Trachurus species present both in Atlantic and Mediterranean waters: T. Trachurus, T. mediterraneus and T. picturatus. In total, 666 individuals were screened from 5 Mediterranean and 6 Atlantic areas. Two African areas were also sampled for T. Trachurus. No dif- ferentiation was revealed among European populations within the 3 studied species. Additionally, no sign of Atlantic-Mediterranean division was found, probably due to the fact that specific life history traits provide the Trachurus species with flexibility to oceanographical constraints and give them the ability to migrate long distances. Differentiation was only revealed between European and African populations of T. Trachurus, reinforcing the existence of the T. Trachurus capensis subspecies in African waters. Populations are probably under long and stable demographic equilibrium conditions as indicated by high haplotypic and nucleotide diversity values for all 3 species. Thus, mtDNA could be a powerful tool in determining the taxonomic distinctiveness of individual populations and spe- cies, and therefore, aid in setting priorities for future management policies. The present results are also discussed in comparison with the results of previous cytochrome b sequence analysis of the 3 Trachurus species.
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Discrimination of three Trachurus species using both mitochondrial- and nuclear-based DNA approaches.
Journal of agricultural and food chemistry, 2003Co-Authors: Nikoletta Karaiskou, And Alexander Triantafyllidis, Costas TriantaphyllidisAbstract:A double-DNA approach was developed to discriminate the three Trachurus species that abide in European waters: T. Trachurus, T. mediterraneus, and T. picturatus. The analysis aimed at both mitochondrial and nuclear loci. Polymerase Chain Reaction (PCR) amplification of the cytochrome b gene of mtDNA was followed by restriction analysis with three species-specific enzymes: NlaIII, NciI, and BsmAI. Digestion with these endonucleases yielded species-specific electrophoretic profiles. The universality of the results was verified by screening a large number of individuals from 12 geographical regions covering most of the distribution of the species. Additionally, the nuclear multicopy 5S rRNA gene was selected as an alternative candidate for the discrimination of the three Trachurus species. A simple agarose gel electrophoretic analysis of the amplicons proved to be capable of leading to unambiguous identification of the three Trachurus species. Thus, the double-DNA methodology presented here allows the accura...
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Genetic Identification and Phylogeny of Three Species of the Genus Trachurus Based on Mitochondrial DNA Analysis
Marine Biotechnology, 2003Co-Authors: Nikoletta Karaiskou, Apostolos Apostolidis, Alexandros Triantafyllidis, Anastasia Kouvatsi, Costas TriantaphyllidisAbstract:The genetic identification and the phylogenetic relationships of 3 European species of the genus Trachurus (T. Trachurus, T. mediterraneus, and T. picturatus) across their geographical distribution, have been investigated by mitochondrial DNA analysis. Both cytochrome b and 16S ribosomal DNA sequence analysis revealed the existence of several species-specific positions that distinguish the 3 studied species. Genetic distances between the species indicated that T. mediterraneus and T. picturatus are more closely related than T. Trachurus. Similar topologies have been produced by neighbor-joining, maximum-likelihood, and maximum-parsimony trees, and they were in accordance with previous taxonomic classification. Internucleotide and intranucleotide diversity of T. picturatus was 2 times higher than that of T. mediterraneus and T. Trachurus, possibly owing to the low levels of fishing pressure for T. picturatus. This is the first report of the phylogenetic relationships of the 3 Trachurus species and provides a possible scenario of the time of divergence related to the closure of the Gibraltar Straits. In addition, the present results can be used for genetic identification of the 3 species, even from the early stage of eggs, and for detection of commercial fraud.
