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Parasitology Research Aug 2023Amphipods Eogammarus tiuschovi were experimentally infected by the acanthocephalan Echinorhynchus gadi (Acanthocephala: Echinorhynchidae). Within the first four days...
Amphipods Eogammarus tiuschovi were experimentally infected by the acanthocephalan Echinorhynchus gadi (Acanthocephala: Echinorhynchidae). Within the first four days post-infection, acanthors of the acanthocephalan caused the cellular response of the host, which ended with their complete encapsulation on day 4 post-infection. The acanthors obtained through the experiment were examined ultrastructurally. Two syncytia (frontal and epidermal) and a central nuclear mass are found in the acanthor's body. The frontal syncytium has 3-4 nuclei and contains secretory granules with homogeneous, electron-dense contents. Since the secretory granules occupy only the anterior one-third of this syncytium, it is suggested that the contents of these granules are involved in the acanthor's migration through the gut wall of the amphipod. The central nuclear mass consists of an aggregation of fibrillar bodies and a few electron-light nuclei distributed on the periphery. Some of these nuclei, located near the central nuclear mass, are assumed to be a source of the acanthocephalan's internal organs. The epidermal syncytium surrounds the frontal syncytium and the central nuclear mass. It is represented by a superficial cytoplasmic layer, but the bulk of the cytoplasm is concentrated in the posterior one-third of the acanthor's body. Syncytial nuclei are evenly distributed throughout the cytoplasm. The muscular system of the acanthors consists of 10 longitudinal muscle fibers located below the superficial cytoplasmic layer and two muscle retractors crossing the frontal syncytium.
Topics: Animals; Acanthocephala; Muscles; Amphipoda; Cell Nucleus; Cytoplasm
PubMed: 37338583
DOI: 10.1007/s00436-023-07899-z -
Journal of Helminthology Jun 2023Previous descriptions of (Linstow, 1892) show that specimens vary greatly in the proportions of different body structures, measurements of females and males, number of...
Previous descriptions of (Linstow, 1892) show that specimens vary greatly in the proportions of different body structures, measurements of females and males, number of rows of hooks, and egg measurements, among other features. We redescribe this species from specimens found in southern elephant seal faeces from King George Island. We also provide a molecular characterization, in addition to 5.8S and internal transcribed spacer (ITS) existing sequences. We examined 41 elephant seals, and 30 adult acanthocephalans were found in 15 of them. The specimens were identified as belonging to the genus due to each having a tubular body with an inflated anterior part forming a thorny disk and the posterior part bearing somatic spines on the ventral surface, and genital spines surrounding the genital pore. Individual morphology corresponded to : large size, marked sexual dimorphism, and proboscis with 16-18 rows of spines with 11-15 spines per row. The molecular profile of three specimens of was analysed using 18S rDNA. We inferred phylogenetic relationships of the family Polymorphidae using maximum likelihood and Bayesian inference. We provide an updated morphological redescription for including electron microscopy photographs and molecular data. The 18S gene sequences showed low genetic variation and supported that is a sister to
Topics: Animals; Female; Male; Antarctic Regions; Bayes Theorem; Phylogeny; Acanthocephala; Seals, Earless
PubMed: 37309645
DOI: 10.1017/S0022149X23000238 -
Helminthologia Mar 2023A total of 72 specimens of (Kessler, 1857), (Pallas, 1814), and (Pallas, 1814) from four sampling sites along the Bulgarian section of the Danube River (Kudelin, Novo...
A total of 72 specimens of (Kessler, 1857), (Pallas, 1814), and (Pallas, 1814) from four sampling sites along the Bulgarian section of the Danube River (Kudelin, Novo selo, Koshava, and Kutovo), Northwestern Bulgaria were submitted to ecologohelminthological investigation. During the examination 6 species of helminths have been identified from 3 classes: Trematoda ( (Iwanitzky, 1928) Dollfus, 1960), Acanthocephala ( (Müller, 1780) Lühe, 1911; (Müller, 1776) Lühe, 1911; (Zoega in Müller, 1776) Porta, 1908) and Nematoda ( sp., Jägerskiöld, 1909). Ecological indices of the established endohelminth species were tracked. The four sampling sites from the Danube River are new habitats for the discovered endohelminth species of racer goby, monkey goby, and round goby. The three goby species are new host records: and for ; for , and sp. New species of helminths are found in the helminth fauna of the three studied species of gobies from the Danube River and the river basin ( of ) and in Bulgaria ( of ; , and sp. of ). The pathogenic species helminths for the fish and humans are found.
PubMed: 37305671
DOI: 10.2478/helm-2023-0008 -
Helminthologia Mar 2023We describe a population of the acanthocephalan Johnston, 1937 (Polymorphidae) from a California sea lion (Lesson, 1828) in California using novel scanning electron...
Revision of Johnston, 1937 (Acanthocephala: Polymorphidae) from a North American population using novel SEM images, Energy Dispersive X-ray Analysis, and molecular analysis.
We describe a population of the acanthocephalan Johnston, 1937 (Polymorphidae) from a California sea lion (Lesson, 1828) in California using novel scanning electron microscopy (SEM) images, Energy Dispersive x-ray analysis (EDXA), and molecular analysis for the first time. The taxonomic history of is replete with accounts using only line drawings some of which proved erroneous. The distribution of ventral spines on the female trunk has been the primary distinction between and Lincicome, 1943, its junior synonym; being continuous in the latter but discontinuous posteriorly in the former species. The distribution of ventral spines is invariably discontinuous in males. Our redescription and SEM images help to resolve this issue further validating the synonymy. Morphological variability has been documented between our California population and others from various host species in California, South Australia, South Shetlands, and the Argentinian coast. Our SEM images document features not previously detectable in line drawings, erroneously reported or missed in previous accounts. The EDXA spectra show high levels of calcium and phosphorous and low levels of sulfur characteristic of EDXA for other species of Lühe, 1904 provide support for the diagnostic distinction of . EDXA spectra were shown to be species specific and have diagnostic value in the taxonomy of the Acanthocephala. Our molecular analysis used amplification of 18S of ribosomal DNA and cytochrome c oxidase 1 (Cox1) gene. Phylogenetic analyses for Cox1 gene revealed a close relationship between Zdzitowiecki, 1984 and The phylogenetic trees confirmed that the isolates belonged to . The haplotype network inferred by Cox1 with sequences revealed that haplotypes clearly separated from each other and formed clusters related to samples from the Northern Hemisphere (the USA and Mexico), and the second from the Southern Hemisphere (Argentina, Brazil and Peru).
PubMed: 37305667
DOI: 10.2478/helm-2023-0003 -
Parasitology Research Aug 2023The objective of this study is to use DNA barcoding to link cystacanths and adults belonging to the acanthocephalans Corynosoma australe found in the Southeastern...
The objective of this study is to use DNA barcoding to link cystacanths and adults belonging to the acanthocephalans Corynosoma australe found in the Southeastern Pacific Ocean off the coast central from Peru. We sampled three species of commercial fish (Paralichthys adspersus (Steindachner), Paralabrax humeralis (Valenciennes), and Cheilodactylus variegatus (Valenciennes)) and two South American sea lions, Otaria byronia, stranded on the beaches of the city of Huacho and Barranca, Lima province. A total of 509 acanthocephalan larvae were found in the body cavity of 95 fish (prevalence 54.28%, total mean intensity 8.64). A total of 127 adult worms were found in the large intestine from two South American sea lions (P= 100%, MI= 63.5). A total of 203 larvae from P. humeralis were isolates (P=65.71%; MI= 8.83; MA=5.8), 235 (P=54.29%; MI= 12.37; MA= 6.71) from C. variegatus, and 71 (P=42.86%; MI= 4.73; MA= 2.03) from P. adspersus. All adult and larval specimens were morphologically identified as C. australe. They were generated cytochrome c oxidase subunit 1 (cox1) gene sequences of specimens and were compared with available data from GenBank. Molecular phylogenetic analysis supported our morphological identification, where the Peruvian isolates formed a clade with other isolates of C. australe from other countries of the American continent. Of the sequences obtained, two haplotypes were detected and were not identical with previous reports. Based on both DNA barcoding and morphological analyses, our finding represents the first molecular data of C. australe from Peru and the report of Cheilodactylus variegatus as a new paratenic host on the central coast, extending the knowledge and distribution range of this acanthocephalan in Southeastern Pacific Ocean.
Topics: Animals; Peru; Sea Lions; DNA Barcoding, Taxonomic; Phylogeny; Pacific Ocean; Acanthocephala; Fishes; Larva
PubMed: 37291358
DOI: 10.1007/s00436-023-07889-1 -
Environmental Toxicology and Chemistry Sep 2023Parasites can affect their hosts in various ways, and this implies that parasites may act as additional biotic stressors in a multiple-stressor scenario, resembling...
Parasites can affect their hosts in various ways, and this implies that parasites may act as additional biotic stressors in a multiple-stressor scenario, resembling conditions often found in the field if, for example, pollutants and parasites occur simultaneously. Therefore, parasites represent important modulators of host reactions in ecotoxicological studies when measuring the response of organisms to stressors such as pollutants. In the present study, we introduce the most important groups of parasites occurring in organisms commonly used in ecotoxicological studies ranging from laboratory to field investigations. After briefly explaining their life cycles, we focus on parasite stages affecting selected ecotoxicologically relevant target species belonging to crustaceans, molluscs, and fish. We included ecotoxicological studies that consider the combination of effects of parasites and pollutants on the respective model organism with respect to aquatic host-parasite systems. We show that parasites from different taxonomic groups (e.g., Microsporidia, Monogenea, Trematoda, Cestoda, Acanthocephala, and Nematoda) clearly modulate the response to stressors in their hosts. The combined effects of environmental stressors and parasites can range from additive, antagonistic to synergistic. Our study points to potential drawbacks of ecotoxicological tests if parasite infections of test organisms, especially from the field, remain undetected and unaddressed. If these parasites are not detected and quantified, their physiological effects on the host cannot be separated from the ecotoxicological effects. This may render this type of ecotoxicological test erroneous. In laboratory tests, for example to determine effect or lethal concentrations, the presence of a parasite can also have a direct effect on the concentrations to be determined and thus on the subsequently determined security levels, such as predicted no-effect concentrations. Environ Toxicol Chem 2023;42:1946-1959. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
Topics: Animals; Parasites; Aquatic Organisms; Environmental Pollutants; Fishes; Nematoda; Water Pollutants, Chemical
PubMed: 37283208
DOI: 10.1002/etc.5689 -
Folia Parasitologica Apr 2023Strange oceanographic events such as El Niño and La Niña may have indirect effects on the local transmission processes of intestinal parasites due to the reduction or...
Strange oceanographic events such as El Niño and La Niña may have indirect effects on the local transmission processes of intestinal parasites due to the reduction or increase in populations of potential intermediate or definitive hosts. A total of 713 individuals of Lutjanus inermis (Peters) were collected over an 8-year period (October 2015 to July 2022) from Acapulco Bay, Mexico. Parasite communities in L. inermis were quantified and analysed to determine if they experienced interannual variations in species composition and structure as a result of local biotic and abiotic factors influenced by oceanographic events, such as El Niño-Southern Oscillation (ENSO), or La Niña, the cool phase of the ENSO climate pattern. Twenty-six taxa of metazoan parasites were recovered and identified: two Monogenea, eight Digenea, two Acanthocephala, four Nematoda, one Cestoda, seven Copepoda, and two Isopoda. Species richness at the component community level (8 to 17 species) was similar to reported richness in other species of Lutjanus Bloch. Parasite communities of L. inermis exhibited high inter-annual variation in the abundance of component species of parasite. However, the species richness and diversity were fairly stable over time. Climatic episodes of El Niño and La Niña probably generated notable changes in the structure of local food webs, thus indirectly influencing the transmission rates of intestinal parasite species. Changes in species composition and community structure of parasites possibly were due to variations in feeding behaviour during the events and differences in the host body size.
Topics: Humans; Animals; Parasites; Perciformes; Nematoda; El Nino-Southern Oscillation; Acanthocephala
PubMed: 37265202
DOI: 10.14411/fp.2023.010 -
Parasitology International Oct 2023This study aimed to analyze helminth assemblage in Rhinella dorbignyi regarding host gender, size and mass in two sampling sites in southern Brazil, and to report new...
This study aimed to analyze helminth assemblage in Rhinella dorbignyi regarding host gender, size and mass in two sampling sites in southern Brazil, and to report new parasite associations. Anurans (n = 100) were collected in two localities from Rio Grande do Sul (RS) state, Brazil, from 2017 to 2020. Nineteen taxa (adults and larval forms) belonging to Nematoda, Acanthocephala, Digenea, and Cestoda were found in different infection sites. Cosmocercidae gen. spp., Physaloptera liophis, Catadiscus sp., and Cylindrotaenia americana were the dominant taxa in helminth assemblage. Female anurans showed higher helminth species richness than males considering the total sample (two localities) or one of the two localities. However, prevalence and mean intensity of infection did not show any significant difference between genders. Mean intensity of infection was significantly higher (19.52) in Laranjal locality. Host body size does not influence helminth abundance, as infections did not show significant correlation snout-vent length (SVL) nor body mass (BM) of anurans. The findings reveal anurans of R. dorbignyi may be intermediate, paratenic and definitive host for these parasites. Plagiorchioidea helminths (Digenea), Physaloptera liophis, larvae of Acuariidae and Spiroxys sp. (Nematoda), and cystacanth of Lueheia sp. (Acanthocephala) constitute new records for R. dorbignyi. Additionally, this is the first record of Cylindrotaenia americana larvae in this host species. Resulting information increases the knowledge on biodiversity and parasite-host relations and may help future conservation programs developed in ecosystems in the extreme south of Brazil.
Topics: Animals; Female; Male; Ecosystem; Bufonidae; Host-Parasite Interactions; Helminthiasis, Animal; Helminths; Acanthocephala; Nematoda; Larva; Brazil
PubMed: 37244362
DOI: 10.1016/j.parint.2023.102766 -
Journal of Fish Diseases Aug 2023Acanthocephalosis is caused by the endoparasite Neoechynorhyncus buttnerae and affects fish farmed in the Amazon. This study assessed the efficacy of therapeutic...
Acanthocephalosis is caused by the endoparasite Neoechynorhyncus buttnerae and affects fish farmed in the Amazon. This study assessed the efficacy of therapeutic levamisole hydrochloride (LVC) baths against N. buttnerae and its effects on juvenile tambaqui blood parameters. In vitro and in vivo tests were carried out, the latter employing two experimental therapeutic LVC bath protocols. Concerning in vitro efficacy, the T75 (75 mg.L LVC) and T100 (mg.L LVC) treatments were 100% effective in 15 min, while the T50 (50 mg.L LVC) and T25 (25 mg.L LVC) treatments required parasite exposure for 45 and 60 min, respectively. During exposure, the parasites displayed reduced motility, proboscis retraction, coiling into a spiral shape, body rigidity and swelling. The LVC LC for juvenile tambaqui was 115 mg.L . Regarding in vivo efficacy for Protocol I (8-h bath), the T125 resulted in 82% effectiveness, while in Protocol II (two 8-h baths with a 24-h interval), the T115 treatment (115 mg.L LVC) achieved 95.6% effectiveness without clinical intoxication signs, despite behavioural changes. No significant changes were observed in fish blood parameters. LVC was, therefore, highly effective both in vitro and in vivo in controlling the acanthocephalan N. buttnerae without compromising tambaqui juvenile homeostasis.
Topics: Animals; Levamisole; Aquaculture; Fish Diseases; Anthelmintics; Acanthocephala; Characiformes
PubMed: 37218384
DOI: 10.1111/jfd.13789 -
The Science of the Total Environment Aug 2023Acanthocephalans, intestinal parasites of vertebrates, are characterised by orders of magnitude higher metal accumulation than free-living organisms, but the mechanism...
Acanthocephalans, intestinal parasites of vertebrates, are characterised by orders of magnitude higher metal accumulation than free-living organisms, but the mechanism of such effective metal accumulation is still unknown. The aim of our study was to gain new insights into the high-resolution localization of elements in the bodies of acanthocephalans, thus taking an initial step towards elucidating metal uptake and accumulation in organisms under real environmental conditions. For the first time, nanoscale secondary ion mass spectrometry (NanoSIMS) was used for high-resolution mapping of 12 elements (C, Ca, Cu, Fe, N, Na, O, P, Pb, S, Se, and Tl) in three selected body parts (trunk spines, inner part of the proboscis receptacle and inner surface of the tegument) of Dentitruncus truttae, a parasite of brown trout (Salmo trutta) from the Krka River in Croatia. In addition, the same body parts were examined using transmission electron microscopy (TEM) and correlated with NanoSIMS images. Metal concentrations determined using HR ICP-MS confirmed higher accumulation in D. truttae than in the fish intestine. The chemical composition of the acanthocephalan body showed the highest density of C, Ca, N, Na, O, S, as important and constitutive elements in living cells in all studied structures, while Fe was predominant among trace elements. In general, higher element density was found in trunk spines and tegument, as body structures responsible for substance absorption in parasites. The results obtained with NanoSIMS and TEM-NanoSIMS correlative imaging represent pilot data for mapping of elements at nanoscale resolution in the ultrastructure of various body parts of acanthocephalans and generally provide a contribution for further application of this technique in all parasite species.
Topics: Animals; Spectrometry, Mass, Secondary Ion; Acanthocephala; Trout; Microscopy, Electron, Transmission; Intestines; Metals
PubMed: 37169189
DOI: 10.1016/j.scitotenv.2023.164010