Molecular phylogenetics and diagnosis of Anisakis, Pseudoterranova, and Contracaecum from northern Pacific marine mammals.
01 Dec 2005-Journal of Parasitology (American Society of Parasitologists)-Vol. 91, Iss: 6, pp 1413-1429
TL;DR: Phylogenetic analysis of LSU sequences revealed strong support for the monophyly of Anisakinae, Contracaecum plus Phocascaris, Pseudoterranova, and Anisakis, which is primarily consistent with previously published phenograms based on multilocus electrophoretic data.
Abstract: Individual specimens of Anisakis, Pseudoterranova, and Contracaecum collected from marine mammals inhabiting northern Pacific waters were used for comparative diagnostic and molecular phylogenetic analyses. Forty-eight new sequences were obtained for this study of 14 Anisakis taxa, 8 Pseudoterranova taxa, 4 Contracaecum taxa, and 4 outgroup species. Partial 28S (LSU) and complete internal transcribed spacer (ITS-1, 5.8S, ITS-2) ribosomal DNA was amplified by the polymerase chain reaction and sequenced. Sequences of ITS indicated that Pseudoterranova specimens from Zalophus californianus (California sea lion), Mirounga angustirostris (northern elephant seal), Phoca vitulina (harbor seal), Enhydra lutris (sea otter), and Eumetopias jubatus (Steller's sea lion) exactly matched P. decipiens s. str., extending the host and geographic range of this species. Anisakis from northern Pacific marine mammals were most closely related to members of the A. simplex species complex. Comparison of Anisakis ITS sequences diagnosed the presence of A. simplex C in 2 M. angustirostris hosts, which is a new host record. Anisakis specimens from Phocoena phocoena (harbor porpoise), Lissodelphis borealis (Pacific rightwhale porpoise), and E. jubatus included 3 ITS sequences that did not match any known species. Contracaecum adults obtained from Z. californianus were most closely related to C. ogmorhini s.l. and C. rudolphii, but ITS sequences of these Contracaecum specimens did not match C. ogmorhini s. str. or C. margolisi. These novel Anisakis and Contracaecum ITS sequences may represent previously uncharacterized species. Phylogenetic analysis of LSU sequences revealed strong support for the monophyly of Anisakinae, Contracaecum plus Phocascaris, Pseudoterranova, and Anisakis. Phylogenetic trees inferred from ITS sequences yielded robustly supported relationships for Pseudoterranova and Anisakis species that are primarily consistent with previously published phenograms based on multilocus electrophoretic data.
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01 Jan 2011
TL;DR: In this paper, three species of the Anisakids (Anisakis pegreffii, Anisakis simplex 'C', and Anisaki simplex s.s., were identified with the use of sequences from the internal transcribed spacers (ITS1 and ITS2) and the 5.8s subunit of the nuclear ribosomal DNA.
Abstract: Members of the Anisakidae are known to infect over 200 pelagic fish species and have been frequently used as biological tags to identify fish populations. Despite information on the global distribution of Anisakis species, there is little information on the genetic diversity and population structure of this genus, which could be useful in assessing the stock structure of their fish hosts. From 2005 through 2008, 148 larval anisakids were recovered from Pacific sardine (Sardinops sagax) in the California Current upwelling zone and were genetically sequenced. Sardines were captured off Vancouver Island, British Columbia in the north to San Diego, California in the south. Three species, Anisakis pegreffii, Anisakis simplex 'C', and Anisakis simplex s.s., were identified with the use of sequences from the internal transcribed spacers (ITS1 and ITS2) and the 5.8s subunit of the nuclear ribosomal DNA. The degree of nematode population structure was assessed with the use of the cytochrome c oxidase 2 (cox2) mitochondrial DNA gene. All 3 Anisakis species were distributed throughout the study region from 32°N to 50°N latitude. There was no association between sardine length and either nematode infection intensity or Anisakis species recovered. Larval Anisakis species and mitochondrial haplotype distributions from both parsimony networks and analyses of molecular variance revealed a panmictic distribution of these parasites, which infect sardines throughout the California Current ecosystem. Panmictic distribution of the larval Anisakis spp. populations may be a result of the presumed migratory pathways of the intermediate host (the Pacific sardine), moving into the northern portion of the California Current in summer and returning to the southern portion to overwinter and spawn in spring. However, the wider geographic range of paratenic (large piscine predators), and final hosts (cetaceans) can also explain the observed distribution pattern. As a result, the recovery of 3 Anisakis species and a panmictic distribution of their haplotypes could not be used to confirm or deny the presence of population subdivision of Pacific sardines in the California Current system.
4 citations
TL;DR: A latitudinal variation in the parasitological indexes of C. pelagicum is suggested, which is related to changes in the diet of the Magellanic penguins during their winter migration in the Southwestern Atlantic Ocean.
Abstract: Magellanic penguins, Spheniscus magellanicus, are frequently found along the coast of Brazil during the winter migration. However, there are very few ecological studies of the parasite fauna of these birds, especially of the adults, which are found dead on Brazilian beaches. Moreover, no studies of parasites of the Magellanic penguins found on the Brazilian coast have evaluated adult or larval nematodes during winter migration so far. Thus, this work is the first one to investigate the parasitism by anisakid nematodes comparatively between young and adult specimens of S. magellanicus in southern Brazil. Parasitological indexes were compared in relation to host gender, parasite development stage and gender, and sites of infection. The gastrointestinal tract of 36 specimens of Magellanic penguins found dead along the coast of Paraná and Rio Grande do Sul states, were analyzed. The nematode fauna was composed of a single species, the anisakid, Contracaecum pelagicum. In Rio Grande do Sul, the young specimens of S. magellanicus were more intensely and abundantly parasitized by C. pelagicum than the adult ones. The stomach and the intestine were the organs that showed highest mean density of infection by adult and larval nematodes, respectively, in the hosts collected in both locations. A high prevalence was observed in both areas, although no differences in the parasitism between male and female penguins were detected. The young Magellanic penguins found in Paraná were on average less parasitized than the ones found in Rio Grande do Sul. These results, together with data available in the literature, suggest a latitudinal variation in the parasitological indexes of C. pelagicum, which are related to changes in the diet of the Magellanic penguins during their winter migration in the Southwestern Atlantic Ocean.
4 citations
Cites background from "Molecular phylogenetics and diagnos..."
...In the marine environment, nematodes of the genus Contracaecum Railliet & Henry, 1912 (Ascaridida, Anisakidae) parasitize several fish species during the larval stage, and marine mammals and piscivorous birds are the definitive hosts (Vicente et al. 1995, Torres et al. 2000, Nadler et al. 2005)....
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Patent•
30 Jan 2008TL;DR: In this article, a molecular method based on real-time PCR for the detection of the presence of Anisakis spp. and Pseudoterranova spp in fish fillets and fish derived food products was proposed.
Abstract: A molecular method based on real time PCR for the detection of the presence of Anisakis spp. and Pseudoterranova spp. parasites in fish fillets and fish- derived food products, such as babyfood, surimi, fish slices, fish sticks and the like, as well as for performing a relative quantification of nematode larvae content, comprises the steps of: - preparing a first amplicon from the ITS-I region specifically able to identify all species belonging to Anisakis and Pseudoterranova species, and a second amplicon able to amplify DNA from any host DNA, such as fish, and from any organic component or foodstuff, said amplicons being located on redundant genomic regions providing more power to detect a PCR product in degraded samples; - testing the primer pairs in the same real time PCR conditions on reference samples made from various mixtures of Anisakid nematodes and fish; - for fish fillets (not products): quantifying the larval mass in the fish sample by calculation versus a known reference; - for fish fillets and products: calculating the amount of Anisakid DNA versus the amount of total DNA in each sample. A mo lecular method based on real time PCR f or discriminating dif f erent Anis akid species in order to test the geographic provenance of Anisakid-containing f ish, comprises : - aligning the ITS l sequences of dif f erent Anisakid species typical of dif ferent predetermined seas, - designing a real time PCR assay based on detection of sequence variations, - determining whether a fish (and product containing fish) coming from a predetermined sea is contaminated by a given Anisakid species.
3 citations
TL;DR: This article used morphological and genetic identification to document metazoan parasites of cetaceans and pinnipeds from 28 carcasses salvaged in California between 1974 and 2002, including whales, dolphins, porpoises, sea lions, and seals.
Abstract: We used morphological and genetic identification to document metazoan parasites of cetaceans and pinnipeds from 28 carcasses salvaged in California between 1974 and 2002, including whales, dolphins, porpoises, sea lions, and seals. Nematodes found included Anisakis simplex (s.l.), A. simplex (s.s.), Pseudoterranova decipiens (s.l.), Pseudoterranova sp., Contracaecum ogmorhini (s.l.), Contracaecum sp., Stenurus cf. minor, Pharurus cf. dalli, and Otostrongylus circumlitus. Cestodes found included Phyllobothrium delphini and Tetrabothrius sp. The acanthocephalan Bolbosoma capitatum, and the arthropod Halarachne miroungae, also were documented. Tetrabothrius sp. in the pygmy beaked whale (Mesoplodon peruvianus) and P. delphini in the Eastern North Pacific long-beaked common dolphin (Delphinus delphis bairdii) constitute two new host records.
3 citations
Cites methods from "Molecular phylogenetics and diagnos..."
...…mt DNA cox2 gene from those specimens of Anisakis was amplified using the primers 210 50CACCAACTC TTAAAATTATC and 211 50TTTTCT AGTTATATAGATTGRTTYAT from Nadler and Hudspeth (2000) and Nadler et al. (2005) spanning mtDNA nucleotide position 10639–11248 as defined in Ascaris suum (Accession #X54253)....
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Dissertation•
01 Jan 2012
3 citations
Cites background from "Molecular phylogenetics and diagnos..."
...8 Pseudoterranova consists of at least seven species (Nadler et al. 2005), of which five species, including P....
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...The genus 8 Pseudoterranova consists of at least seven species (Nadler et al. 2005), of which five species, including P. decipiens, have a cosmopolitan distribution (Berland 2006)....
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...Molecular methods have revealed that the specie P. decipiens is actually a complex of four species: P. decipiens, P. krabbei, P. bulbosa and P. azarasi (Nadler et al. 2005)....
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676 citations
TL;DR: More than 260 specimens of fish, belonging to 64 species, have been searched for nematode parasites and 9 species of fish were found to be free of nematodes.
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373 citations
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