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Animals : An Open Access Journal From... Mar 2024The present study is the first to analyse the parasite fauna of sole , dab , hake , whiting , and plaice in the Pomeranian Bay, as well as saithe from the Szczecin...
The present study is the first to analyse the parasite fauna of sole , dab , hake , whiting , and plaice in the Pomeranian Bay, as well as saithe from the Szczecin Lagoon (Poland). The aim of this study was to determine the occurrence of parasites in migrating and rare fish in the Pomeranian Bay and the Szczecin Lagoon and to determine the composition of the diet of these fish. The fish for analysis were obtained in the years 2010-2019. The typical marine nematode ) , rarely recorded in Poland, was found, in addition to the following parasites: , , sp., () , , , , , , and . Because the fish species analysed in the study are not typically present in the Baltic (with the exception of plaice), and because we do not know how long they feed while they are in the Baltic, we cannot be certain which parasites they acquired in the water bodies analysed in the study and which were introduced during the migration of fish. Although these fish are outside of their normal geographic range (except for plaice), in the new environment, there were enough suitable intermediate hosts for the parasites of these fish to complete their life cycle and survive.
PubMed: 38612268
DOI: 10.3390/ani14071029 -
International Journal of Food... Jan 2024Zoonotic nematodes of the family Anisakidae are highly common in many marine fish species, which act as paratenic hosts for the third larval stage. In the fish, these...
Zoonotic nematodes of the family Anisakidae are highly common in many marine fish species, which act as paratenic hosts for the third larval stage. In the fish, these parasites may migrate from the fish's gastro-intestinal tract (GI-tract) further to the coelomic cavity and muscles, making them a possible contamination source of bacteria they carry on their cuticle and in their GI-tract. A previous study revealed no apparent effect of Anisakis simplex on spoilage of fish, but the equally common anisakid species Pseudoterranova decipiens has a larger body surface potentially increasing the bacterial load brought into the fish muscle upon migration. As the presence of shelf-life reducing spoilage bacteria in the microbiome of this anisakid species has been demonstrated, the objective of the present study was to assess the potential shelf-life reducing effect of P. decipiens in fresh fish fillets stored in a domestic refrigerator. Atlantic cod was used as a model since members of the cod family are the third most consumed marine fish globally and it has the highest prevalence of P. decipiens infections. Infected and non-infected codfish fillet portions were collected and microbiologically analyzed at day 0 and day 4 of storage in a domestic fridge. Three isolation media were used to enhance maximum bacterial recovery and isolates were identified using MALDI-TOF MS and 16S rRNA gene sequencing. In parallel to the microbiological examination, sensory analysis was performed daily on the cod fillets to evaluate the freshness of the fish. Results revealed the presence of typical spoilage bacteria (e.g., Pseudomonas sp., Photobacterium sp.) in all fish, but based on the total viable counts, total HS-producing bacteria, and sensory analysis, there were no objective indications to assume an increased fish spoilage rate by the presence and migration P. decipiens. Additionally, a beta-diversity comparison revealed no significant differences in microbiota composition between infected and non-infected fish parts, though individual heterogeneity in microbiome composition among Atlantic codfish individuals was found. As total viable counts did, however, exceed the guideline limits for fresh fish, further research should now focus on the role of the candling step as a potential source of post-harvest contamination. As such, anisakid infection might still accelerate fish spoilage, though now in an indirect way.
Topics: Animals; Gadus morhua; RNA, Ribosomal, 16S; Ascaridoidea; Fishes; Anisakis
PubMed: 37977078
DOI: 10.1016/j.ijfoodmicro.2023.110426 -
Journal of Fish Diseases Jan 2024A dispersion of Anisakidae nematodes (particularly Contracaecum osculatum) among marine organisms in the Baltic Sea has been reported over the last decade. This is in...
A dispersion of Anisakidae nematodes (particularly Contracaecum osculatum) among marine organisms in the Baltic Sea has been reported over the last decade. This is in line with an increase in the number of grey seal that act as final host for Contracaecum osculatum and Pseudoterranova sp., and are thus indispensable for the completion of their life cycles. Most attention has been paid to zoonotic nematode species, like Pseudoterranova sp., which have been noted in commercially important fish in the area. Little is known about the spread and transmission of Pseudoterranova sp. in the Baltic Sea. The aim of this study was to investigate whether sprat may play a role as a transport host for this Anisakidae. Samples were collected in three areas of the southern Baltic Sea (south and east of Bornholm, Słupsk Farrow and the Gulf of Gdańsk) during a research cruise in August 2019. A visual inspection of the viscera of 556 sprats was conducted. Parasites were identified using anatomomorphological and molecular methods. Nematodes were recorded only in sprat caught southeast of Bornholm (prevalence 2.7%; intensity of infection 1-4; abundance 0.05). Molecular identification revealed the presence of Pseudoterranova decipiens. This is the first report of P. decipiens in sprat from the Baltic Sea. Sprat is likely a transmitter of P. decipiens in the Baltic Sea food web.
Topics: Animals; Fish Diseases; Fishes; Ascaridoidea; Baltic States
PubMed: 37750419
DOI: 10.1111/jfd.13866 -
Parasitology International Dec 2023Species of the genus Pseudoterranova, infect kogiid cetaceans and pinnipeds. However, there is mounting molecular evidence that those from cetaceans and pinnipeds are...
Resurrection of genus Phocanema Myers, 1959, as a genus independent from Pseudoterranova Mozgovoĭ, 1953, for nematode species (Anisakidae) parasitic in pinnipeds and cetaceans, respectively.
Species of the genus Pseudoterranova, infect kogiid cetaceans and pinnipeds. However, there is mounting molecular evidence that those from cetaceans and pinnipeds are not congeneric. Here, we provide further evidence of the non-monophyly of members of Pseudoterranova from phylogenetic analyses of the conserved nuclear LSU rDNA gene, entire ITS rDNA region and mtDNA cox2 gene, and identify morphological characters that may be used to distinguish the members of the two clades. We propose the resurrection of the genus Phocanema, with Ph. decipiens (sensu stricto) as the type species, to encompass Ph. decipiens, Ph. azarasi, Ph. bulbosa, Ph. cattani and Ph. krabbei, all parasites of pinnipeds. We propose to restrict the conception of genus Pseudoterranova, which now harbours two species infecting kogiid whales; Ps. kogiae (type species) and Ps. ceticola. Members of the genera Phocanema and Pseudoterranova differ by the shape and orientation of the lips, relative tail lengths, adult size, type of final host (pinniped vs. cetacean) and phylogenetic placement based on nuclear rDNA and mtDNA cox2 sequences.
Topics: Animals; Caniformia; Parasites; Phylogeny; Cyclooxygenase 2; Ascaridoidea; DNA, Ribosomal; Whales; DNA, Mitochondrial
PubMed: 37573003
DOI: 10.1016/j.parint.2023.102794 -
Folia Parasitologica May 2023Evolutionary and ecological processes affecting the interactions between hosts and parasites in the aquatic environment are at display in the Baltic Sea, a young and...
Evolutionary and ecological processes affecting the interactions between hosts and parasites in the aquatic environment are at display in the Baltic Sea, a young and ecologically unstable marine ecosystem, where fluctuating abiotic and biotic factors affect the parasitofauna in fish. The dynamic infections of Baltic cod, a subpopulation of the Atlantic cod (Gadus morhua Linnaeus), with third stage anisakid nematode larvae of Pseudoterranova decipiens (Krabbe, 1878) and Contracaecum osculatum (Rudolphi, 1802) have increased following a significant increase of the Baltic grey seal Halichoerus grypus (Fabricius) population in the region. Cod serves as a paratenic host and marine mammals, pinnipeds, are definitive hosts releasing parasite eggs, with faeces, to the marine environment, where embryonation and hatching of the third stage larva take place. The parasite has no obligate intermediate hosts, but various invertebrates, smaller fish and cod act as paratenic hosts transmitting the infection to the seal. Contracaecum osculatum has an impact on the physiological performance of the cod, which optimises transmission of the larva from fish to seal. Thus, a muscle mass decrease of nearly 50% may result from heavy C. osculatum infections, probably amplified by a restricted food availability. The muscle atrophy is likely to reduce the escape reactions of the fish when meeting a foraging seal. In certain regions, where fish and seals are restricted in their migration patterns, such as the semi-enclosed Baltic Sea, the predation may contribute to a severe cod stock depletion. The parasites are zoonotic and represent a human health risk, when consumers ingest insufficiently heat- or freeze-treated infected products. Marked infections of the cod were previously reported during periods with elevated seal populations (late 19th and middle 20th century) and various scenarios for management of risk factors are evaluated in an evolutionary context.
Topics: Humans; Animals; Parasites; Ecosystem; Fishes; Seals, Earless; Larva; Ascaridoidea; Gadus morhua; Fish Diseases
PubMed: 37265200
DOI: 10.14411/fp.2023.011 -
Parasitology Dec 2022Northeast Arctic cod, saithe and haddock are among the most important fisheries resources in Europe, largely shipped to various continental markets. The present study...
Anisakid parasites (Nematoda: Anisakidae) in 3 commercially important gadid fish species from the southern Barents Sea, with emphasis on key infection drivers and spatial distribution within the hosts.
Northeast Arctic cod, saithe and haddock are among the most important fisheries resources in Europe, largely shipped to various continental markets. The present study aimed to map the presence and distribution of larvae of parasitic nematodes in the Anisakidae family which are of socioeconomic and public health concern. Fishes were sourced from commercial catches during winter or spring in the southern Barents Sea. Samples of fish were inspected for nematodes using the UV-press method while anisakid species identification relied on sequencing of the mtDNA gene. (s.s.) was the most prevalent and abundant anisakid recorded, occurring at high infection levels in the viscera and flesh of cod and saithe, while being less abundant in haddock. (s.l.) larvae, not found in the fish flesh, showed moderate-to-high prevalence in saithe, haddock and cod, respectively. Most spp. larvae occurred at low-to-moderate prevalence, and low abundance, in the viscera () and flesh ( (s.s.) and ) of cod, only 2 (s.s.) appeared in the flesh of saithe. Body length was the single most important host-related factor to predict overall abundance of anisakid larvae in the fish species. The spatial distribution of larvae in the fish flesh showed much higher abundances in the belly flaps than in the dorsal fillet parts. Trimming of the flesh by removing the belly flaps would reduce larval presence in the fillets of these gadid fish species by 86–91%.
Topics: Animals; Parasites; Fish Diseases; Ascaridoidea; Anisakis; Fishes; Larva; Gadiformes; Anisakiasis
PubMed: 36321524
DOI: 10.1017/S0031182022001305 -
Parasitology International Dec 2022The nematode genera Anisakis s.l. and Pseudoterranova (Anisakidae) include causative agents of anisakiasis and pseudoterranovosis, parasitic diseases resulting from...
The nematode genera Anisakis s.l. and Pseudoterranova (Anisakidae) include causative agents of anisakiasis and pseudoterranovosis, parasitic diseases resulting from eating undercooked or raw fish or squid. Species in both genera have thus attracted considerable attention especially in public health and taxonomic studies. The phylogenetic relationships of these genera within the subfamily Anisakinae, however, remain to be investigated with dense taxonomic sampling. In this study, we collected an anisakid third-stage larva, and identified it morphologically and molecularly as Pseudoterranova ceticola. Phylogeny of 15 anisakine species, including the newly collected specimen of Ps. ceticola, was reconstructed based on sequences of three mitochondrial (cox1, cox2, and 12S rRNA) and two nuclear (ITS and 28S rRNA) regions. The obtained tree suggested the non-monophyly of Anisakis s.l. and Pseudoterranova. Anisakis s.l. was divided into two groups, which are distinguished from each other by the shape of the ventriculus. Based on phylogenetic relationships and morphology, three species with a shorter ventriculus ("A." brevispiculata, "A." paggiae, and "A." physeteris) were assigned to the genus Skrjabinisakis, as recently proposed. Pseudoterranova ceticola was distantly related to the monophyletic Ps. decipiens species complex. Although the phylogenetic position of the type species Ps. kogiae has not been investigated due to a lack of sequence data, this species may morphologically and ecologically resemble Ps. ceticola, inferring a close kinship between the two species.
Topics: Animals; Anisakiasis; Anisakis; Ascaridoidea; Larva; Phylogeny; RNA, Ribosomal, 28S
PubMed: 35863674
DOI: 10.1016/j.parint.2022.102631 -
Emerging Infectious Diseases Jun 2022Human Pseudoterranova decipiens larval infections were diagnosed by molecular analysis of mitochondrial cox1 and nd1 genes in 12 health check-up patients in South Korea...
Human Pseudoterranova decipiens larval infections were diagnosed by molecular analysis of mitochondrial cox1 and nd1 genes in 12 health check-up patients in South Korea during 2002-2020. Based on high genetic identity (99.3%-100% for cox1 and 96.7%-98.0% for nd1), we identified all 12 larvae as P. decipiens sensu stricto.
Topics: Animals; Anisakiasis; Anisakis; Ascaridoidea; Humans; Larva; Republic of Korea
PubMed: 35608950
DOI: 10.3201/eid2806.212483 -
Journal of Fish Diseases Aug 2022The recent advances in molecular methods and data processing have facilitated research on anisakid nematodes. While most research efforts were made regarding the genus...
The recent advances in molecular methods and data processing have facilitated research on anisakid nematodes. While most research efforts were made regarding the genus Anisakis, since this genus is held responsible for the majority of reported clinical signs, there is still a demand for data on the genus Pseudoterranova. Several case studies of severe invasive anisakidosis affecting various organs caused by species of the P. decipiens complex have been described. To better understand the way these parasites might infest their fish host, we examined whether parasite location within the fish host affects gene expression. A de novo assembly of the transcriptome of Pseudoterranova bulbosa, isolated from North Atlantic cod, was analysed for patterns of differential gene expression between samples taken from liver and viscera. We additionally searched for homologs to known nematode allergens, to give a first estimate of the potential allergenicity of P. bulbosa. There was a subtle difference in the gene expression of samples taken from liver and viscera. Seventy genes were differentially expressed, 32 genes were upregulated in parasites isolated from liver and 38 genes were upregulated in parasites from viscera. Homologs of five nematode allergens were identified among the genes expressed by P. bulbosa. Our transcriptome of P. bulbosa will be a valuable resource for further meta-analyses and resequencing projects.
Topics: Allergens; Animals; Anisakis; Ascaridoidea; Communicable Diseases; Fish Diseases; Gadus morhua; Gene Expression; Larva
PubMed: 35475516
DOI: 10.1111/jfd.13630 -
Parasitology Jul 2022In the Anisakidae family, there are nematodes, most of which are parasitic for important commercial fish species. Both public health risks and socio-economic problems...
In the Anisakidae family, there are nematodes, most of which are parasitic for important commercial fish species. Both public health risks and socio-economic problems are attributed to these parasites. Despite these concerns, knowledge of the metabolism of these parasites remains unknown. Therefore, the main objective of this study was to investigate the receptors of drugs and oxidative metabolic status of two Anisakidae species, (s. s.) and (s. s.), under the influence of anthelminthic drugs, ivermectin (IVM) and pyrantel (PYR), at different concentrations: 1.56, 3.125 and 6.25 g mL of culture medium for 3, 6, 9, 12 and 72 h. The mRNA expressions of the -aminobutyric acid receptor, acetylcholine receptor subunits, adenosine triphosphate-binding cassette transporters and antioxidative enzymes were determined. The total antioxidant capacity and glutathione -transferase activity were also examined. To the best of the authors' knowledge, this is the first time that IVM and PYR have been tested against these parasitic nematodes.
Topics: Animals; Ascaridoidea; Fish Diseases; Fishes
PubMed: 35443901
DOI: 10.1017/S0031182022000543