co-variation between the intensity of behavioural manipulation and parasite development time in an acanthocephalan-amphipod system.pomphorhynchus laevis, a fish acanthocephalan parasite, manipulates the behaviour of its gammarid intermediate host to increase its trophic transmission to the definitive host. however, the intensity of behavioural manipulation is variable between individual gammarids and between parasite populations. to elucidate causes of this variability, we compared the level of phototaxis alteration induced by different parasite sibships from one population, using experimental infections of gammarus pulex b ...201020796137
the parasite community of the nase chondrostoma nasus (l. 1758) from austrian rivers.between april 2003 and november 2006 a total of 191 individuals of the predominantly herbivorous fish species nase chondrostoma nasus (l. 1758) were examined for parasites from six river sites in austria. the following parasite taxa were recovered - ciliata: trichodina sp., chilodonella piscicola, ichthyophthirius multifiliis; myxozoa: myxobolus muelleri (cysts) and myxobolus sp. (cysts); monogenea: dactylogyrus vistulae, d. chondrostomi and dactylogyrus spp., gyrodactylus sp., diplozoon paradox ...201020831848
interspecific differences in carotenoid content and sensitivity to uvb radiation in three acanthocephalan parasites exploiting a common intermediate host.few endoparasite species are pigmented. acanthocephalans are an exception however, with several species being characterised by yellow to orange colouration both at the immature (cystacanth) and adult stages. however, the functional and adaptive significance of carotenoid-based colourations in acanthocephalans remains unclear. one possibility is that the carotenoid content of acanthocephalan cystacanths acts as a protective device against ultra-violet radiation (uvr) passing through the transluce ...201120833172
intraspecific conflict over host manipulation between different larval stages of an acanthocephalan parasite.competitive interactions between coinfecting parasites are expected to be strong when they affect transmission success. when transmission is enhanced by altering host behaviour, intraspecific conflict can lead to 'coinfection exclusion' by the first-in parasite or to a 'sabotage' of behavioural manipulation by the youngest noninfective parasite. we tested these hypotheses in the acanthocephalan parasite pomphorhynchus laevis, reversing phototaxis in its intermediate host gammarus pulex. no evide ...201020964763
intestinal immune response of silurus glanis and barbus barbus naturally infected with pomphorhynchus laevis (acanthocephala).immunopathological and ultrastructural studies were conducted on the intestine of barbel barbus barbus and sheatfish silurus glanis that were naturally infected with the acanthocephalan pomphorhynchus laevis. enteric helminths often cause inflammation of the digestive tract, inducing the recruitment of different types of immune cells at the site of infection. the results of our study clearly demonstrated that mast cells (mc) were the dominant immune cells which occur at the site of inflammation ...201121226724
paratenic hosts as regular transmission route in the acanthocephalan pomphorhynchus laevis: potential implications for food webs.although trophically transmitted parasites are recognized to strongly influence food-web dynamics through their ability to manipulate host phenotype, our knowledge of their host spectrum is often imperfect. this is particularly true for the facultative paratenic hosts, which receive little interest. we investigated the occurrence and significance both in terms of ecology and evolution of paratenic hosts in the life cycle of the fish acanthocephalan pomphorhynchus laevis. this freshwater parasite ...201121814810
protection first then facilitation: a manipulative parasite modulates the vulnerability to predation of its intermediate host according to its own developmental stage.many trophically transmitted parasites with complex life cycles manipulate their intermediate host behavior in ways facilitating their transmission to final host by predation. this facilitation generally results from lowering host's antipredatory defenses when the parasite is infective to the final host. however, a recent theoretical model predicts that an optimal parasitic strategy would be to protect the intermediate host from predation when noninfective, before switching to facilitation when ...201121884065
metazoan parasites from herring (clupea harengus l.) as biological indicators in the baltic sea.zoographical distribution of metazoan fish parasites in herring, clupea harengus, from the baltic sea was analysed in order to use them as potential biological indicators. a total of 210 herring from six different sampling sites were investigated, harbouring 12 different parasite species [five digeneans (d), one cestode (c), three nematodes (n) and three acanthocephalans (a)]. the distribution of the parasite species differed according to region, with a distinct gradient of decreasing species ri ...201425119368
helminthofauna of ohrid gudgeon (gobio ohridanus karaman, 1924) from the lake ohrid,, 94 specimens of gudgeon (gobio ohridanus karaman, 1924) from the macedonian part of the lake ohrid were examined and 61 fishes (64.89%) were infected with parasites. the presence of 4 parasite species was established: dactylogyrus cryptomeres f. typica (monogenea), cystidicoloides tenuissima and philometra ovata (nematoda), and pomphorhynchus laevis (acanthocephala). the highest prevalence and intensity of infection was with dactylogyrus cryptomeres f. typica (59.57%; mean intensity 6.07) ...201525911039
evolutionary anatomy of the muscular apparatus involved in the anchoring of acanthocephala to the intestinal wall of their vertebrate hosts.different conceptions exist regarding structure, function, and evolution of the muscles that move the acanthocephalan presoma, including the proboscis, i.e., the usually hooked hold-fast anchoring these endoparasites to the intestinal wall of their vertebrate definitive hosts. in order to clarify the unresolved issues, we carried out a light microscopic analysis of series of semi-thin sections and whole mounts representing the three traditional acanthocephalan classes: archiacanthocephala (macra ...201728233104
understanding trophic interactions in host-parasite associations using stable isotopes of carbon and nitrogen.stable isotope analysis of carbon and nitrogen can deliver insights into trophic interactions between organisms. while many studies on free-living organisms are available, the number of those focusing on trophic interactions between hosts and their associated parasites still remains scarce. in some cases information about taxa (e.g. acanthocephalans) is completely missing. additionally, available data revealed different and occasionally contrasting patterns, depending on the parasite's taxonomic ...201728212669
histopathology of catostomus commersoni (white sucker) infected with the acanthocephalan pomphorhynchus bulbocolli.this study was undertaken to assess the damage caused by pomphorhynchus bulbocolli to catostomus commersoni (white sucker). three specimens of c. commersoni were collected during early september 2014 via gill net from canadarago lake (otsego county, new york), then dissected and examined for intestinal parasites. one c. commersoni , collected from a tributary of otsego lake (otsego county, new york), was used as a control in this study because it was not infected with intestinal helminths. upon ...201627341296
interactions of warming and exposure affect susceptibility to parasite infection in a temperate fish species.predicting how elevated temperatures from climate change alter host-parasite interactions requires understandings of how warming affects host susceptibility and parasite virulence. here, the effect of elevated water temperature and parasite exposure level was tested on parasite prevalence, abundance and burden, and on fish growth, using pomphorhynchus laevis and its fish host squalius cephalus. at 60 days post-exposure, prevalence was higher at the elevated temperature (22 °c) than ambient tempe ...201627225942
seasonal profile of metal accumulation in the acanthocephalan pomphorhynchus laevis: a valuable tool to study infection dynamics and implications for metal monitoring.a large number of studies demonstrated that acanthocephalans exhibit a high metal accumulation potential and thus can be used as sensitive accumulation indicators. however, similar to free-living bioindicators, a seasonal variation in metal concentrations in parasites might occur. accordingly, the influence of seasonality has to be elucidated if parasites should be applied as sentinels.201627216617
occurrence of immune cells in the intestinal wall of squalius cephalus infected with pomphorhynchus laevis.a sub-population of 34 specimens of chub, squalius cephalus, was sampled from the river brenta (northern italy) and examined for ecto- and endo-parasites. pomphorhynchus laevis (acanthocephala) was the only enteric helminth encountered. immunofluorescence and ultrastructural studies were conducted on the intestines of chub. near the site of parasite's attachment, mucous cells, mast cells (mcs), neutrophils and rodlet cells (rcs) were found to co-occur within the intestinal epithelium. the number ...201526434712
identifying a key host in an acanthocephalan-amphipod system.trophically transmitted parasites may use multiple intermediate hosts, some of which may be 'key-hosts', i.e. contributing significantly more to the completion of the parasite life cycle, while others may be 'sink hosts' with a poor contribution to parasite transmission. gammarus fossarum and gammarus roeseli are sympatric crustaceans used as intermediate hosts by the acanthocephalan pomphorhynchus laevis. gammarus roeseli suffers higher field prevalence and is less sensitive to parasite behavio ...201526303006
influence of host nutritional condition on post-infection traits in the association between the manipulative acanthocephalan pomphorhynchus laevis and the amphipod gammarus pulex.several parasites with complex life-cycles induce phenotypic alterations in their intermediate hosts. according to the host manipulation hypothesis, such phenotypic alterations are supposed to increase the fitness of the parasite at the expense of that of its intermediate hosts through increasing the probability of transmission to next hosts. although the phenomenon has received a large attention, the proximate factors modulating the occurrence and intensity of host manipulation remain poorly kn ...201526223476
enteric neuromodulators and mucus discharge in a fish infected with the intestinal helminth pomphorhynchus vertebrates, the presence of enteric worms can induce structural changes to the alimentary canal impacting on the neuroendocrine system, altering the proper functioning of the gastrointestinal tract and affecting the occurrence and relative density of endocrine cells (ecs). this account represents the first immunohistochemistry and ultrastructure-based study which documents the intimate relationship between the intestinal mucous cells and ecs in a fish-helminth system, investigating the poten ...201526152567
pomphorhynchus laevis (acanthocephala) from the sava river basin: new insights into strain formation, mtdna-like sequences and dynamics of we report the genetic variability and presence of mtdna-like sequences of pomphorhynchus laevis from the chub, squalius cephalus, caught at the sampling sites along the sava river and its tributary the sutla river in croatia. sequences of the cytochrome c oxidase subunit 1 (coi) gene of the recovered p. laevis specimens were used for haplotype network construction and phylogenetic analysis. these analyses showed that some specimens contained mitochondrial-like sequences, and they uncovered ...201525728305
fine structure and cellular responses at the host-parasite interface in a range of fish-helminth systems.a series of ultrastructural-based studies were conducted on the interface region in different fish-helminth systems: (a) an intestinal infection of the cestode monobothrium wageneri in tench, tinca tinca; (b) an extensive intestinal submucosa and mucosal infection in tench by metacercariae of an unidentified digenean trematode; (c) an intestinal infection in brown trout, salmo trutta, by the acanthocephalan dentitruncus truttae; (d) an extraintestinal infection by larvae of the acanthocephalan, ...201525613477
responses of squalius cephalus intestinal mucous cells to pomphorhynchus laevis.intestinal mucous cell numbers and their glycoconjugate composition were investigated by histochemical methods in uninfected chub, squalius cephalus, and in conspecifics naturally parasitised with the acanthocephalan pomphorhynchus laevis. a sub-population of 42 chub from the river tiber (perugia, italy) were sampled and screened for ecto and endoparasites. no parasites were found in gills and in other visceral organs of chub and p. laevis appeared to be the only enteric worm encountered. in all ...201525486440
multidimensionality in host manipulation mimicked by serotonin injection.manipulative parasites often alter the phenotype of their hosts along multiple dimensions. 'multidimensionality' in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. we compared multidimensionality in 'host manipulation' between two closely related amphipods, gammarus fossarum and gammarus pulex, naturally and experimen ...201425339729
does fish reproduction and metabolic activity influence metal levels in fish intestinal parasites, acanthocephalans, during fish spawning and post-spawning period?application of fish intestinal parasites, acanthocephalans, as bioindicators in metal exposure assessment usually involves estimation of their metal levels and bioconcentration factors. metal levels in parasite final host, fishes, are influenced by fish physiology but there is no data for acanthocephalan metal levels. gastrointestinal zn, fe, mn, cd, ag levels in european chub (squalius cephalus l.) from the sava river were significantly higher during chub spawning (april/may) compared to the po ...201425048939
parasite-induced alteration of plastic response to predation threat: increased refuge use but lower food intake in gammarus pulex infected with the acanothocephalan pomphorhynchus laevis.larvae of many trophically-transmitted parasites alter the behaviour of their intermediate host in ways that increase their probability of transmission to the next host in their life cycle. before reaching a stage that is infective to the next host, parasite larvae may develop through several larval stages in the intermediate host that are not infective to the definitive host. early predation at these stages results in parasite death, and it has recently been shown that non-infective larvae of s ...201424291320
effect of acanthocephalan infection on metal, total protein and metallothionein concentrations in european chub from a sava river section with low metal the present study, the importance of considering fish intestinal parasites i.e. the acanthocephalans in metal exposure assessment was estimated under low metal contamination conditions. two acanthocephalan species, pomphorhynchus laevis and acanthocephalus anguillae were examined in 59 specimens of european chub (squalius cephalus l.) sampled at 5 locations along the sava river, croatia. concentrations of essential (cu, mn) and non-essential (ag, cd, pb) metals were higher in intestinal paras ...201323856403
a bio-inspired swellable microneedle adhesive for mechanical interlocking with tissue.achieving significant adhesion to soft tissues while minimizing tissue damage poses a considerable clinical challenge. chemical-based adhesives require tissue-specific reactive chemistry, typically inducing a significant inflammatory response. staples are fraught with limitations including high-localized tissue stress and increased risk of infection, and nerve and blood vessel damage. here inspired by the endoparasite pomphorhynchus laevis, which swells its proboscis to attach to its host's inte ...201323591869
comparison of the metal accumulation capacity between the acanthocephalan pomphorhynchus laevis and larval nematodes of the genus eustrongylides sp. infecting barbel (barbus barbus).metal uptake and accumulation in fish parasites largely depends on the parasite group with acanthocephalans showing the highest accumulation rates. additionally, developmental stage (larvae or adult) as well as parasite location in the host are suggested to be decisive factors for metal bioconcentration in parasites. by using barbel (barbus barbus) simultaneously infected with nematode larvae in the body cavity and adult acanthocephalans in the intestine, the relative importance of all of these ...201323332036
parasite-induced suppression of aggregation under predation risk in a freshwater amphipod: sociality of infected amphipods.recent findings suggest that grouping with conspecifics is part of the behavioural defences developed by amphipod crustaceans to face predation risk by fish. amphipods commonly serve as intermediate hosts for trophically transmitted parasites. these parasites are known for their ability to alter intermediate host phenotype in a way that promotes predation by definitive hosts, where they reproduce. if aggregation in amphipods dilutes the risk to be preyed on by fish, then it may dilute the probab ...201222940109
larval size in acanthocephalan parasites: influence of intraspecific competition and effects on intermediate host behavioural changes.parasites often face a trade-off between exploitation of host resources and transmission probabilities to the next host. in helminths, larval growth, a major component of adult parasite fitness, is linked to exploitation of intermediate host resources and is influenced by the presence of co-infecting conspecifics. in manipulative parasites, larval growth strategy could also interact with their ability to alter intermediate host phenotype and influence parasite transmission.201222876882
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