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Parasite (Paris, France) 2022The morphology of cystacanths and adults of Profilicollis altmani (Perry, 1942) Van Cleave, 1947 (Polymorphidae) were studied from the Pacific mole crab Emerita analoga...
A comparative assessment of the morphology of Profilicollis altmani (Acanthocephala, Polymorphidae) from crustaceans and shore birds in Peru, with special notes on hook elemental analysis (EDXA), SEM imaging, histopathology, and molecular profile.
The morphology of cystacanths and adults of Profilicollis altmani (Perry, 1942) Van Cleave, 1947 (Polymorphidae) were studied from the Pacific mole crab Emerita analoga (Stimpson) (Crustacea, Hippidae) and Belcher's gull Larus belcheri (Vigors) (Aves, Laridae), respectively, in Peru. Comparative morphometrics with accounts of other populations of P. altmani from elsewhere off the Pacific and Atlantic coasts of North and South America revealed marked intraspecific population variations. We report scanning electron micrographs (SEM) of new features, not before noted or captured in line drawings by earlier observers. We further present microscope images that reveal internal details not previously reported or possible to see with SEM. Energy dispersive X-ray analysis (EDXA) revealed unusual patterns in the chemistry of proboscis hooks especially the high sulfur and diminished phosphorous and calcium in hook tips and low sulfur and high levels of phosphorous and calcium at mid hooks. The size and shape of all hooks of the cystacanths are reported for the first time. Histopathological studies in L. belcheri from Peru are also included. Cystacanths of P. altmani from California were also analyzed for molecular patterns and compared with other sequences reported from other locations. The molecular data and the analysis of our new sequences of cytochrome oxidase I (COI) showed that haplotypes of P. altmani had low genetic variation; the species is not geographically structured, and within its clade no monophyletic group is formed.
Topics: Acanthocephala; Animals; Anomura; Birds; Electrons; Helminthiasis, Animal; Peru; X-Rays
PubMed: 35191831
DOI: 10.1051/parasite/2022005 -
Ecology and Evolution Oct 2023Studies on host-parasite systems that have experienced distributional shifts, range fragmentation, and population declines in the past can provide information regarding...
Studies on host-parasite systems that have experienced distributional shifts, range fragmentation, and population declines in the past can provide information regarding how parasite community richness and genetic diversity will change as a result of anthropogenic environmental changes in the future. Here, we studied how sequential postglacial colonization, shifts in habitat, and reduced host population sizes have influenced species richness and genetic diversity of (Acanthocephala: Polymorphidae) parasites in northern European marine, brackish, and freshwater seal populations. We collected population samples from Arctic, Baltic, Ladoga, and Saimaa ringed seal subspecies and Baltic gray seals, and then applied COI barcoding and triple-enzyme restriction-site associated DNA (3RAD) sequencing to delimit species, clarify their distributions and community structures, and elucidate patterns of intraspecific gene flow and genetic diversity. Our results showed that species diversity reflected host colonization histories and population sizes, with four species being present in the Arctic, three in the Baltic Sea, two in Lake Ladoga, and only one in Lake Saimaa. We found statistically significant population-genetic differentiation within all three species that occur in more than one seal (sub)species. Genetic diversity tended to be high in populations originating from Arctic ringed seals and low in the landlocked populations. Our results indicate that acanthocephalan communities in landlocked seal populations are impoverished with respect to both species and intraspecific genetic diversity. Interestingly, the loss of genetic diversity within species seems to have been less drastic than in their seal hosts, possibly due to their large local effective population sizes resulting from high infection intensities and effective intra-host population mixing. Our study highlights the utility of genomic methods in investigations of community composition and genetic diversity of understudied parasites.
PubMed: 37869427
DOI: 10.1002/ece3.10608 -
Aquatic Toxicology (Amsterdam,... Jun 2022Physiologically based pharmacokinetic (PBPK) models have been applied to simulate the absorption, distribution, metabolism, and elimination of various toxicants in fish....
Physiologically based pharmacokinetic (PBPK) models have been applied to simulate the absorption, distribution, metabolism, and elimination of various toxicants in fish. This approach allows for considering metal accumulation in intestinal parasites. Unlike "semi" physiologically-based models developed for metals, metal accumulation in fish was characterised based on metal-specific parameters (the fraction in blood plasma and the tissue-blood partition coefficient) and physiological characteristics of the fish (the blood flow and the tissue weight) in our PBPK model. In the model, intestinal parasites were considered a sink of metals from the host intestine. The model was calibrated with data for the system of the chub Squalius cephalus and the acanthocephalan Pomphorhynchus tereticolliis. Metal concentrations in this fish-parasite system were monitored in Ag and Co treatments in duplicate during a 48-day exposure phase (Ag and Co were added to tap water at concentrations of 1 and 2 µg/L, respectively) and a 51-day depuration phase. Their concentrations in the gills increased during the exposure phase and decreased in the depuration phase. A similar pattern was observed for Ag concentrations in other chub organs, while a relatively stable pattern for Co indicates regulations in the accumulation of essential metals by chubs. The metals were taken up by the acanthocephalans at similar rate constants. These results indicate that metal availability to parasites, which is determined by the internal distribution and fate, is critical to metal accumulation in the acanthocephalans. The high concentration of Ag in the liver as well as the high rate of Ag excretion from the liver to the intestine might contribute to higher concentrations of metals in the bile complexes in the intestine, which are available to the parasites, but not to the reabsorption by the host intestine. The opposite pattern might explain the lower availability of Co to the acanthocephalans.
Topics: Acanthocephala; Animals; Cyprinidae; Environmental Monitoring; Fish Diseases; Helminthiasis, Animal; Metals; Parasites; Water Pollutants, Chemical
PubMed: 35489172
DOI: 10.1016/j.aquatox.2022.106178 -
Gastroenterology May 2018
Topics: Acanthocephala; Adult; Animals; Anisakiasis; DNA, Helminth; Diagnosis, Differential; Double-Balloon Enteroscopy; Helminthiasis; Humans; Jejunum; Male; Polymerase Chain Reaction
PubMed: 28823859
DOI: 10.1053/j.gastro.2017.08.020 -
Evolution; International Journal of... Sep 2022Parasitic worms (helminths) with complex life cycles divide growth and development between successive hosts. Using data from 597 species of acanthocephalans, cestodes,...
Parasitic worms (helminths) with complex life cycles divide growth and development between successive hosts. Using data from 597 species of acanthocephalans, cestodes, and nematodes with two-host life cycles, we found that helminths with larger intermediate hosts were more likely to infect larger, endothermic definitive hosts, although some evolutionary shifts in definitive host mass occurred without changes in intermediate host mass. Life-history theory predicts parasites to shift growth to hosts in which they can grow rapidly and/or safely. Accordingly, helminth species grew relatively less as larvae and more as adults if they infected smaller intermediate hosts and/or larger, endothermic definitive hosts. Growing larger than expected in one host, relative to host mass/endothermy, was not associated with growing less in the other host, implying a lack of cross-host trade-offs. Rather, some helminth orders had both large larvae and large adults. Within these taxa, however, size at maturity in the definitive host was unaffected by changes to larval growth, as predicted by optimality models. Parasite life-history strategies were mostly (though not entirely) consistent with theoretical expectations, suggesting that helminths adaptively divide growth and development between the multiple hosts in their complex life cycles.
Topics: Animals; Biological Evolution; Helminths; Host-Parasite Interactions; Larva; Life Cycle Stages; Parasites
PubMed: 35860949
DOI: 10.1111/evo.14574 -
Parasitology Feb 2020Parasites directly and indirectly influence the important interactions among hosts such as competition and predation through modifications of behaviour, reproduction and...
Parasites directly and indirectly influence the important interactions among hosts such as competition and predation through modifications of behaviour, reproduction and survival. Such impacts can affect local biodiversity, relative abundance of host species and structuring of communities and ecosystems. Despite having a firm theoretical basis for the potential effects of parasites on ecosystems, there is a scarcity of experimental data to validate these hypotheses, making our inferences about this topic more circumstantial. To quantitatively test parasites' role in structuring host communities, we set up a controlled, multigenerational mesocosm experiment involving four sympatric freshwater crustacean species that share up to four parasite species. Mesocosms were assigned to either of two different treatments, low or high parasite exposure. We found that the trematode Maritrema poulini differentially influenced the population dynamics of these hosts. For example, survival and recruitment of the amphipod Paracalliope fluviatilis were dramatically reduced compared to other host species, suggesting that parasites may affect their long-term persistence in the community. Relative abundances of crustacean species were influenced by parasites, demonstrating their role in host community structure. As parasites are ubiquitous across all communities and ecosystems, we suggest that the asymmetrical effects we observed are likely widespread structuring forces.
Topics: Acanthocephala; Animals; Crustacea; Female; Fresh Water; Helminths; Host-Parasite Interactions; Male; Population Dynamics; Species Specificity
PubMed: 31679526
DOI: 10.1017/S0031182019001483 -
BMC Genomics Aug 2021Seisonidea (also Seisonacea or Seisonidae) is a group of small animals living on marine crustaceans (Nebalia spec.) with only four species described so far. Its...
BACKGROUND
Seisonidea (also Seisonacea or Seisonidae) is a group of small animals living on marine crustaceans (Nebalia spec.) with only four species described so far. Its monophyletic origin with mostly free-living wheel animals (Monogononta, Bdelloidea) and endoparasitic thorny-headed worms (Acanthocephala) is widely accepted. However, the phylogenetic relationships inside the Rotifera-Acanthocephala clade (Rotifera sensu lato or Syndermata) are subject to ongoing debate, with consequences for our understanding of how genomes and lifestyles might have evolved. To gain new insights, we analyzed first drafts of the genome and transcriptome of the key taxon Seisonidea.
RESULTS
Analyses of gDNA-Seq and mRNA-Seq data uncovered two genetically distinct lineages in Seison nebaliae Grube, 1861 off the French Channel coast. Their mitochondrial haplotypes shared only 82% sequence identity despite identical gene order. In the nuclear genome, distinct linages were reflected in different gene compactness, GC content and codon usage. The haploid nuclear genome spans ca. 46 Mb, of which 96% were reconstructed. According to ~ 23,000 SuperTranscripts, gene number in S. nebaliae should be within the range published for other members of Rotifera-Acanthocephala. Consistent with this, numbers of metazoan core orthologues and ANTP-type transcriptional regulatory genes in the S. nebaliae genome assembly were between the corresponding numbers in the other assemblies analyzed. We additionally provide evidence that a basal branching of Seisonidea within Rotifera-Acanthocephala could reflect attraction to the outgroup. Accordingly, rooting via a reconstructed ancestral sequence led to monophyletic Pararotatoria (Seisonidea+Acanthocephala) within Hemirotifera (Bdelloidea+Pararotatoria).
CONCLUSION
Matching genome/transcriptome metrics with the above phylogenetic hypothesis suggests that a haploid nuclear genome of about 50 Mb represents the plesiomorphic state for Rotifera-Acanthocephala. Smaller genome size in S. nebaliae probably results from subsequent reduction. In contrast, genome size should have increased independently in monogononts as well as bdelloid and acanthocephalan stem lines. The present data additionally indicate a decrease in gene repertoire from free-living to epizoic and endoparasitic lifestyles. Potentially, this reflects corresponding steps from the root of Rotifera-Acanthocephala via the last common ancestors of Hemirotifera and Pararotatoria to the one of Acanthocephala. Lastly, rooting via a reconstructed ancestral sequence may prove useful in phylogenetic analyses of other deep splits.
Topics: Acanthocephala; Animals; Genomics; Phylogeny; Rotifera; Transcriptome
PubMed: 34372786
DOI: 10.1186/s12864-021-07857-y -
Biodiversity Data Journal 2020A literature survey was conducted to investigate the host and geographical distribution patterns of three species (Acanthocephala: Polymorphidae), , and . All three...
A literature survey was conducted to investigate the host and geographical distribution patterns of three species (Acanthocephala: Polymorphidae), , and . All three species appear to be restricted to the Northern Hemisphere. Occurrence records of are limited to the Northern Atlantic coasts, while has a circumpolar distribution. The geographical range of encompasses the distributions of the other two species, but also extends into warmer southern regions. Some populations are living with their definitive hosts in very isolated locations, such as in the brackish Baltic Sea or different freshwater lakes (e.g. Lake Saimaa). All three species have a heteroxenous life cycle, comprising a peracaridan intermediate host, a fish paratenic host and a mammalian definitive host. Occasionally, an acanthocephalan may enter an accidental host, from which it is unable to complete its life cycle. The host records reported here are categorised by type, intermediate, paratenic, definitive or accidental. While most of the definitive hosts are shared amongst the three species, showed the broadest range of paratenic hosts, which reflects its more extensive geographical distribution. One aim of this study and extensive literature summary is to guide future sampling efforts and therewith contribute to throw more light on the on-going species and morphotype discussion for this interesting parasite species.
PubMed: 32308529
DOI: 10.3897/BDJ.8.e50500 -
The Science of the Total Environment Sep 2022Acanthocephalans' position in food webs, in close interaction with free-living species, could provide valuable information about freshwater ecosystem health through the...
Acanthocephalans' position in food webs, in close interaction with free-living species, could provide valuable information about freshwater ecosystem health through the viability of the parasites' host populations. We explored Pomphorhynchus laevis cystacanths' and adults' intensities of infection, and the prevalence of infected hosts respectively in their Gammarus pulex intermediate hosts and Squalius cephalus definitive hosts in a Mediterranean river. First, we analysed the relationship between P. laevis intensity of infection, its two hosts populations and the other acanthocephalan species found (Pomphorhynchus tereticollis and Polymorphus minutus). Second, we characterised the influence of bacteriological, physicochemical and biological water parameters on these acanthocephalans, and their intermediate and definitive hosts. This research highlights that P. laevis infection was closely related to their two preferential hosts population in the river. Moreover, P. laevis intensity of infection was positively correlated with organic pollution in the river but negatively correlated with biodiversity and with ecological indexes of quality. Pomphorhynchus laevis could thus benefit from moderate freshwater pollution, which promotes their tolerant intermediate and definitive hosts.
Topics: Acanthocephala; Amphipoda; Animals; Ecosystem; Fresh Water; Parasites
PubMed: 35609694
DOI: 10.1016/j.scitotenv.2022.156091 -
Helminthologia Jun 2019A study screening pet animals (dogs, cats, chinchillas, ferrets, guinea pigs, rabbits, primates, reptiles, and hedgehogs) within Moscow city limits for intestinal...
A study screening pet animals (dogs, cats, chinchillas, ferrets, guinea pigs, rabbits, primates, reptiles, and hedgehogs) within Moscow city limits for intestinal parasitic diseases has been conducted over a period of 6 years. According to the study, parasitic infections caused by intestinal protozoa are found in pet animals more frequently than by intestinal helminths. Although dogs and cats exhibit the highest level of diversity of intestinal parasite species, in the group of exotic animals, helminth infection are found much less frequently and parasitic fauna is represented mostly by intestinal protozoa with a high percentage of mixed infection. The most widespread helminth infeсtion of dogs and cats is toxocarosis (respectively 2.5 and 5.7 %) and the most widespread protozoan infection is sp. (9.8 and 4.6 %). sp. was found in 47.4 % of chinchillas, sp. was more frequently found in ferrets (6.55 %), protozoa from the family Trichomonadida was found in guinea pigs (9 %), sp. in rabbits (13.9 %), a in primates (15.7 %), and eggs from the genera (59 %), along with protozoa from the family Trichomonadida, in reptiles. sp. was most prevalent in hedgehogs (33.4 %). eggs, as well as protozoa from the and genera, were more frequently found in primates. Parasites common to animals and humans, which may become a source of infection for the latter under certain conditions, have been identified in pet animals.
PubMed: 31662681
DOI: 10.2478/helm-2019-0007