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Parasitology Jan 2023Polymorphidae is a monophyletic group of acanthocephalans distributed worldwide. Within this family, is a specialist species that uses a single bird species as a...
Polymorphidae is a monophyletic group of acanthocephalans distributed worldwide. Within this family, is a specialist species that uses a single bird species as a definitive host. is a generalist species that uses a broad spectrum of definitive hosts to complete its life cycle. In the current research, sequences of cytochrome c oxidase subunit 1 () from mitochondrial DNA were generated from 44 specimens of and 76 of distributed sympatrically in 6 biogeographic provinces of Mexico with the objective of characterizing and comparing the population genetic structure of 2 acanthocephalan species with opposing life strategies. The phylogeographic studies indicated that the populations of both species lacked a phylogeographic structure and exhibited high haplotype diversity, low nucleotide diversity and low values among the biogeographic provinces; in combination with negative values on the neutrality test, this suggests that the populations of acanthocephalans are expanding. Paratenic hosts are key for the transmission from intermediate to definitive hosts in the generalist species. However, the inclusion of paratenic hosts does not play a principal role in the population genetic structure of within its distribution along the coasts of Mexico.
PubMed: 36748352
DOI: 10.1017/S0031182023000033 -
Parasites & Vectors Jan 2023Central European aerial insectivores are long-distance migrants that winter in sub-Saharan Africa. Most of them employ the fly-and-forage migrating strategy and differ...
Long-term study reveals central European aerial insectivores as an unusual group of hosts that harbor mostly helminths that are unable to complete life-cycles in the nesting quarters of their hosts.
BACKGROUND
Central European aerial insectivores are long-distance migrants that winter in sub-Saharan Africa. Most of them employ the fly-and-forage migrating strategy and differ in their food composition. The composition and structure of helminth component communities of these hosts are poorly understood, and information regarding seasonality and long-term changes is unavailable.
METHODS
From 1963 to 2022, we analyzed the population trends of helminths in five aerial insectivore species. Namely, we examined Apus apus, Hirundo rustica, Delichon urbicum, Riparia riparia, and Ficedula albicollis; all originated from the Czech Republic.
RESULTS
We identified central European aerial insectivores as hosts that are parasitized mostly by helminths that cannot complete their life-cycles in the nesting quarters of their hosts. This phenomenon is unknown in other bird host species. In contrast, only a single dominant trematode species that completes its life-cycle locally colonized the central European aerial insectivores. All other dominant species of Trematoda, all Nematoda, and all Acanthocephala were dependent on intermediate hosts unavailable in the nesting quarters of the examined bird hosts. Surprisingly, these helminths transmitted from winter quarters or migratory routes were diverse, and many of them were abundant in terms of both prevalence and intensity of infection. The helminth component communities of aerial insectivores were dynamic systems. During the study period, three species became new and regularly encountered members of helminth fauna of examined hosts, and other species gradually increased or decreased their intensity of infection. In contrast to other groups of bird hosts, the dominant helminth species of aerial insectivores did not experience local extinctions or rapid population losses.
CONCLUSIONS
The analysis of helminths of five central European aerial insectivores revealed component communities that heavily rely on completing host-parasite cycles at migration routes or wintering grounds. The composition of the analyzed component communities changed dynamically during the 60-year-long study period, but there was no evidence of large-scale declines in abundance or prevalence.
Topics: Animals; Helminthiasis, Animal; Birds; Czech Republic; Helminths; Acanthocephala; Life Cycle Stages
PubMed: 36703152
DOI: 10.1186/s13071-022-05636-6 -
Revista Brasileira de Parasitologia... 2023This study aims to report the occurrence of two important parasites in farmed tambaqui Colossoma macropomum in the state of Tocantins, the acanthocephalan...
This study aims to report the occurrence of two important parasites in farmed tambaqui Colossoma macropomum in the state of Tocantins, the acanthocephalan Neoechinorhynchus buttnerae and the dinoflagellate protozoan Piscinoodinium pillulare, also suggesting the main treatments to control them. The fish sampled for the study were infected by N. buttnerae, and P. pillulare, with prevalence from 100% and mean intensity from 51.4 to 354,264, respectively. This was the first report on the occurrence of such parasites in C. macropomum in the state of Tocantins. We emphasize the need to adopt good farm management and biosecurity practices to prevent pathogenic agents to enter or leave a property. Reported treatments with synthetic and natural products with positive results are also suggested to treat against those parasites in farmed C. macropomum.
Topics: Animals; Brazil; Fish Diseases; Acanthocephala; Characiformes; Parasites; Dinoflagellida
PubMed: 36651424
DOI: 10.1590/S1984-29612023001 -
Parasite (Paris, France) 2022Sebkha Imlili (Atlantic Sahara) is a salt flat with over 160 permanent holes of hypersaline water generated in the Holocene and inhabited by euryhaline organisms that...
Sebkha Imlili (Atlantic Sahara) is a salt flat with over 160 permanent holes of hypersaline water generated in the Holocene and inhabited by euryhaline organisms that are considered to be relics of the past, including the cichlid fish Coptodon guineensis. We surveyed the fish parasites four times over one year, to i) identify the parasites, and ii) determine possible seasonality in infection patterns. Over 60% of the fish were infected by one to three helminths: an acanthocephalan in the intestine and two digenean metacercariae in the kidney, spleen, liver, muscle, and mesenteries. The acanthocephalan Acanthogyrus (Acanthosentis) cf. tilapiae was identified morphologically and molecularly; only one digenean (the heterophyid Pygidiopsis genata) could be identified molecularly. Both identified parasites were present throughout the sampling periods; the unidentified metacercariae were present only in summer and fall. Mean intensities, but not prevalence of infection by the acanthocephalan, reflected a biannual pattern of transmission. Infection accrued with fish size, possibly due to cannibalism. Because the water holes include only a few invertebrates, the intermediate hosts of these parasites can be inferred to be the gastropod Ecrobia ventrosa for the digeneans and either the copepod Cletocamtpus retrogressus or the ostracod Cyprideis torosa for the acanthocephalan. This ecosystem appears stable and provides a window into the past, as the acanthocephalan likely switched from freshwater tilapia to C. guineensis when the Sebkha formed. However, this is a vulnerable environment where the survival of these parasites depends on interactions maintained among only very few hosts.
Topics: Animals; Cichlids; Parasites; Ecosystem; Acanthocephala; Water; Metacercariae; Fish Diseases
PubMed: 36562431
DOI: 10.1051/parasite/2022064 -
Scientific Reports Dec 2022Trophically transmitted heteroxenous parasites of diverse clades can decrease or reverse antipredator behaviours in their intermediate hosts, thereby increasing their...
Trophically transmitted heteroxenous parasites of diverse clades can decrease or reverse antipredator behaviours in their intermediate hosts, thereby increasing their chances of reaching their final hosts. Such behavioural alterations could result from compromised cognitive abilities affecting fear- or more generally stress-related neurophysiological pathways. We tested this hypothesis in a key model system in the study of parasitic manipulation, the fish acanthocephalan parasite Pomphorhynchus tereticollis and its intermediate crustacean host Gammarus fossarum, using the 'threat of electric shock' paradigm. We exposed uninfected and infected G. fossarum to chronic and/or acute electric shock programs at two different intensities (voltage), and then quantified their sheltering behaviour as a proxy for anxiety-like state. Infected gammarids did not express anxiety-like response to electric shocks, while uninfected gammarids hid more when exposed to acute treatments, and when exposed to the high intensity chronic treatment. Interestingly, the lack of response in infected gammarids depended on parasite developmental stage. Our results support the hypothesis that this acanthocephalan parasite impacts the general anxiety-like circuitry of their intermediate host. Further studies are needed to investigate whether it involves inappropriate processing of information, impaired integration, or altered activation of downstream pathways initiating behavioural action.
Topics: Animals; Host-Parasite Interactions; Acanthocephala; Amphipoda; Fishes; Parasites; Anxiety
PubMed: 36522391
DOI: 10.1038/s41598-022-25484-9 -
Revista Brasileira de Parasitologia... 2022The objective of this study was to investigate the parasites occurrences and to determine the rates of infestation/parasitic infection in juvenile Arapaima gigas from...
The objective of this study was to investigate the parasites occurrences and to determine the rates of infestation/parasitic infection in juvenile Arapaima gigas from seven fish farms in the state of Amazonas, relating to the characteristics of these fish farms. Of the 70 A. gigas evaluated, 43 were infested/infected, with a total of 133 parasites collected. Three fish farms (2, 4, 6) showed the highest levels of prevalence of parasites (100%, 70%, 70%), mean intensity (4.1±2.6, 8.1±9.2, and 2.1±1.3), and mean abundance (4.1±2.6, 5.7±8.1, and 1.5±1.5), respectively. Prevalence ranged from 30% to 100%, mean intensity from 1.0 to 8.1 and mean abundance from 0.3 to 5.7. Monogenea, Digenea, Nematoda (Hysterothylacium sp. and Spirocamallanus sp.) and Acanthocephala (Neoechinorhynchus sp. and Polyacanthorhynchus sp.) were identified. The parasites Hysterothylacium sp. and Neoechinorhynchus sp. were the most prevalent parasites with 31.43% and 15.71%, respectively. The fish presented negative allometry in growth and constant condition factor. Measures to prevent and control the parasitic diseases diagnosed are discussed as well prophylactic practices that contribute to the biosecurity of the farms.
Topics: Animals; Fisheries; Brazil; Fishes; Acanthocephala; Trematoda; Ascaridoidea; Parasites; Fish Diseases
PubMed: 36515319
DOI: 10.1590/S1984-29612022064 -
Interdisciplinary Perspectives on... 2022Limited data exist on acanthocephalan infections of hedgehogs in the world. Our objective was to investigate the prevalence and distribution of infection in hedgehogs...
AIM
Limited data exist on acanthocephalan infections of hedgehogs in the world. Our objective was to investigate the prevalence and distribution of infection in hedgehogs between August 2021 and March 2022 ( = 30) in the east of Iran.
METHODS
At first, infection with was diagnosed based on morphologic features of the adults such as body length, proboscis, and hooks. Spindle-shaped eggs (mean length, 99.1 microns; mean width, 60.1 microns) were obtained from the body cavity of gravid female specimens.
RESULTS
The molecular analysis based on 18S rDNA and COX 1 genes confirmed the morphological identification of isolated . The prevalence of in our sample was 13.3% with 1-10 worms per infected host.
CONCLUSION
In this study, we identify as zoonotic species in hedgehog carcasses for the first time that passed eggs and adult worms, indicating parasite maturation and reproduction. There are a few studies on acanthocephalans in Iran. Therefore, more comparative studies are needed to determine the status of these species.
PubMed: 36313384
DOI: 10.1155/2022/8418752 -
Pathogens (Basel, Switzerland) Sep 2022Dogs are very popular pets that can be infected with a wide diversity of endo- and ectoparasites, some of which have zoonotic potential. The aim of the present study was...
Dogs are very popular pets that can be infected with a wide diversity of endo- and ectoparasites, some of which have zoonotic potential. The aim of the present study was to determine the diversity and prevalence of helminths in rural and urban dogs in Tashkent, Samarkand and Karakalpakstan regions of Uzbekistan. A total of 399 dogs from rural and urban areas were examined by necropsy between November 2016 and March 2022. All helminth species were morphologically identified. A total of 31 species belonging to the classes Trematoda (3), Cestoda (9), Nematoda (18) and Acanthocephala (1) were identified in 378 dogs (94.7%). Twenty-one species are indicated for the helminth fauna of urban dogs and 31 species for rural dog populations. From the 31 species of helminths identified 18 species are zoonotic and four of them () have a significant epidemiological importance. The study showed that the prevalence and diversity of helminths in dogs in rural areas of Uzbekistan is higher than in urban dogs.
PubMed: 36297142
DOI: 10.3390/pathogens11101085 -
Parasites & Vectors Oct 2022Classification of the Acanthocephala, a clade of obligate endoparasites, remains unresolved because of insufficiently strong resolution of morphological characters and...
BACKGROUND
Classification of the Acanthocephala, a clade of obligate endoparasites, remains unresolved because of insufficiently strong resolution of morphological characters and scarcity of molecular data with a sufficient resolution. Mitochondrial genomes may be a suitable candidate, but they are available for a small number of species and their suitability for the task has not been tested thoroughly.
METHODS
Herein, we sequenced the first mitogenome for the large family Rhadinorhynchidae: Micracanthorhynchina dakusuiensis. These are also the first molecular data generated for this entire genus. We conducted a series of phylogenetic analyses using concatenated nucleotides (NUC) and amino acids (AAs) of all 12 protein-coding genes, three different algorithms, and the entire available acanthocephalan mitogenomic dataset.
RESULTS
We found evidence for strong compositional heterogeneity in the dataset, and Micracanthorhynchina dakusuiensis exhibited a disproportionately long branch in all analyses. This caused a long-branch attraction artefact (LBA) of M. dakusuiensis resolved at the base of the Echinorhynchida clade when the NUC dataset was used in combination with standard phylogenetic algorithms, maximum likelihood (ML) and Bayesian inference (BI). Both the use of the AA dataset (BI-AAs and ML-AAs) and the CAT-GTR model designed for suppression of LBA (CAT-GTR-AAs and CAT-GTR-NUC) at least partially attenuated this LBA artefact. The results support Illiosentidae as the basal radiation of Echinorhynchida and Rhadinorhynchidae forming a clade with Echinorhynchidae and Pomporhynchidae. The questions of the monophyly of Rhadinorhynchidae and its sister lineage remain unresolved. The order Echinorhynchida was paraphyletic in all of our analyses.
CONCLUSIONS
Future studies should take care to attenuate compositional heterogeneity-driven LBA artefacts when applying mitogenomic data to resolve the phylogeny of Acanthocephala.
Topics: Animals; Acanthocephala; Phylogeny; Artifacts; Nucleotides; Bayes Theorem; Amino Acids
PubMed: 36261865
DOI: 10.1186/s13071-022-05488-0 -
PeerJ 2022Nemerteans are mostly marine, benthic invertebrates, inhabiting intertidal to hadal zones. Recently, they have been recognized from deep sea with environmental DNA...
Nemerteans are mostly marine, benthic invertebrates, inhabiting intertidal to hadal zones. Recently, they have been recognized from deep sea with environmental DNA (eDNA) metabarcoding of sediment samples whereas any records from the locations and/or the water depth have not been documented in nemertean taxonomic publications to date. It suggests that there are major gaps between deep-sea nemertean fauna observed with eDNA and taxonomic knowledge. During a research expedition in 2021, we obtained a single specimen of eumonostiliferous nemertean from the southern part of Genroku Seamount Chain, the Nishi-Shichito Ridge, where any nemertean species have never been reported. Subsequent morphological and molecular examination reveal that the species is placed in a new genus and herein described as gen. et sp. nov. It resembles shallow-water-dwelling and , but differs from the former in lacking eyes and the latter in possessing well-developed cephalic glands and lacking accessory nerves of lateral nerve cords. In terms of genetic distances based on partial sequences of the cytochrome c oxidase subunit I gene, gen. et sp. nov. is closest to Monostilifera sp. Owase collected from Japan, which is characterized by large four eyes; the COI distance is higher than commonly observed interspecific divergences in eumonostiliferans.
Topics: Animals; Acanthocephala; Japan; Phylogeny
PubMed: 36213503
DOI: 10.7717/peerj.13857