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Cell & Bioscience May 2022A central question in parasitology is why parasites mature and reproduce in some host species but not in others. Yet, a better understanding of the inability of...
BACKGROUND
A central question in parasitology is why parasites mature and reproduce in some host species but not in others. Yet, a better understanding of the inability of parasites to complete their life cycles in less suitable hosts may hold clues for their control. To shed light on the molecular basis of parasite (non-)maturation, we analyzed transcriptomes of thorny-headed worms (Acanthocephala: Pomphorhynchus laevis), and compared developmentally arrested worms excised from European eel (Anguilla anguilla) to developmentally unrestricted worms from barbel (Barbus barbus).
RESULTS
Based on 20 RNA-Seq datasets, we demonstrate that transcriptomic profiles are more similar between P. laevis males and females from eel than between their counterparts from barbel. Impairment of sexual phenotype development was reflected in gene ontology enrichment analyses of genes having differential transcript abundances. Genes having reproduction- and energy-related annotations were found to be affected by parasitizing either eel or barbel. According to this, the molecular machinery of male and female acanthocephalans from the eel is less tailored to reproduction and more to coping with the less suitable environment provided by this host. The pattern was reversed in their counterparts from the definitive host, barbel.
CONCLUSIONS
Comparative analysis of transcriptomes of developmentally arrested and reproducing parasites elucidates the challenges parasites encounter in hosts which are unsuitable for maturation and reproduction. By studying a gonochoric species, we were also able to highlight sex-specific traits. In fact, transcriptomic evidence for energy shortage in female acanthocephalans associates with their larger body size. Thus, energy metabolism and glycolysis should be promising targets for the treatment of acanthocephaliasis. Although inherently enabling a higher resolution in heterosexuals, the comparison of parasites from definitive hosts and less suitable hosts, in which the parasites merely survive, should be applicable to hermaphroditic helminths. This may open new perspectives in the control of other helminth pathogens of humans and livestock.
PubMed: 35642000
DOI: 10.1186/s13578-022-00818-2 -
Zootaxa Oct 2023To date, 31 species assigned to the genus Pallisentis Van cleave, 1928 have been reported from India. The present study includes morphological and molecular descriptions...
Morphological and Molecular Characterization of Two New and Two Already Known Species of the Genus Pallisentis (Acanthocephala: Quadrigyridae) from India with an Update in Key to the Species.
To date, 31 species assigned to the genus Pallisentis Van cleave, 1928 have been reported from India. The present study includes morphological and molecular descriptions of two new species of Pallisentis Van Cleave, 1928, namely P. himachalensis and P. longus from the fresh water fishes Channa punctata (Bloch, 1793) and C. marulius (Hamilton, 1822), respectively, procured from Himachal Pradesh and Chandigarh, India. Of total 35 fishes, 17 were found infected with acanthocephalan parasites. The prevalence of infection was 42.85 and 52.38% for C. punctata and C. marulius, respectively. The morphological characters of P. himachalensis n. sp. include proboscis with 4 circles of hooks with 810 hooks per circle, which gradually decline in size. The trunk in male comprises 1516 circles of collar spines and 2737 circles of trunk spines ending above the anterior testis with syncytial cement gland having 2629 nuclei. The trunk in female comprises of 1418 circles of collar spines and 5573 circles of trunk spines present till the anterior end of reproductive system with additional 34 circles at the posterior end. P. longus n. sp. is the longest species reported in the genus and the length of female reach up to 44 mm. The proboscis comprises 4 circles of proboscis hooks with 910 hooks per circle. In males 1316 circles of the collar spines and 2731 circles of trunk spines are present with syncytial cement gland containing 2025 nuclei. The females are much longer with 1516 circles of collar spines and 6469 circles of trunk spines present till the posterior end. The study also reports two already described species: P. gomtii Gupta and Verma, 1980 from C. punctata and P. nandai Sarkar, 1953 from C. marulius. Total 12 sequences for 4 species have been generated based on 18S, 28S and ITS15.8SITS2 molecular markers. The 18S and ITS15.8SITS2 Bayesian inference trees generated in the present study showed distinct identities of all 4 species. Moreover, the Bayesian inference tree generated in the present study based on 18S showed the clustering of Pallisentis species in three different clades compared to the previous studies in which only two clades within the genus were reported. The molecular analysis showed the monophyletic origin of the genus Pallisentis and does not support subgeneric classification within the genus.
Topics: Female; Male; Animals; Acanthocephala; Bayes Theorem; Fish Diseases; Helminthiasis, Animal; Fishes; India
PubMed: 38221427
DOI: 10.11646/zootaxa.5352.4.8 -
Helminthologia Dec 2023Globally, the exploitation of small pelagic fish, like Pacific mackerel is of great importance due to food industry demand. However, there are few studies regarding its...
Globally, the exploitation of small pelagic fish, like Pacific mackerel is of great importance due to food industry demand. However, there are few studies regarding its parasites load and there are no in this geographic zone. This study aimed to assess the parasitic composition, some temporal changes (during spring and summer) in abundance, prevalence and intensity of infection parasitic of the Pacific mackerel () from Todos Santos Bay, Baja California, Mexico. The parasite fauna of the Pacific mackerel consisted of 1930 parasites (1413 in spring and 517 in summer) distributed in the follow taxa: an Tetraphyllidea (Cestoda), (Monogenea), Didymozoidae (Digenea), sp. (Nematoda), sp. (Acanthocephala) and (Copepoda). The nematodes parasite were the most abundant both in spring with a mean abundance of 27.6 parasites and in summer 8.2 parasites compared with the other taxa like Cestoda, Monogenea, Digenea, Acanthocephala and Copepoda ( = 0.003). The mean intensity of the nematodes in spring and summer was 28.1 and 13.4, respectively. The nematodes prevalence was 90 % in spring and 60 % in summer. In general, the parasite load is more abundant in spring than summer. In summer, absence of taxa as Cestoda and Copepoda were registered. Nematode larvae were present in the fish guts mesentery and inside of the stomach, pyloric caeca, intestine. Also the nematodes were found in the liver, muscle and gonads. The most affected organ by nematodes was the intestine mesentery. The most predominant parasite of this study has been sp. during spring.
PubMed: 38222493
DOI: 10.2478/helm-2023-0039 -
Journal of Helminthology Jan 2021Pallisentis (Pallisentis) nandai Sarkar, 1953 is a freshwater fish parasite restricted to the Indian subcontinent in the Ganga River and its tributaries. It was...
Pallisentis (Pallisentis) nandai Sarkar, 1953 is a freshwater fish parasite restricted to the Indian subcontinent in the Ganga River and its tributaries. It was described from the leaffish, Nandus nandus (Hamilton) from the Ganga River delta at Calcutta. We recovered variant specimens from the same host species from the Ganga near its headwaters at Bijnor about 1500 km away. Our specimens were clearly identifiable as P. nandai but varied considerably from those in the original description, especially in the size of proboscis hooks, receptacle and lemnisci. The original description was incomplete (missing line drawings of female trunk and reproductive system, male trunk, complete proboscis, hooks and hook roots) and inaccurate (proboscis, hooks, receptacle wall), and some measurements were lumped together for both sexes. We provide a complete description and include new morphological information including the first description of para-receptacle structure in the genus Pallisentis Van Cleave, 1928, scanning electron microscopy and microscope images, molecular analysis, and energy dispersive X-ray analysis (EDXA) of hooks and spines of our specimens for the first time. Additional details of proboscis hook roots, trunk spines, micropores and micropore distribution are described. The unique metal composition of hooks (EDXA) demonstrated a considerably high but variable level of sulphur and negligible level of calcium in collar and trunk spines and hook tips, but a higher level of sulphur and calcium at the hook basal arch than at the hook tip and edge. A comparison with the EDXA pattern of another species of Pallisentis, P. İndica Mital & Lal, 1976, were considerably different. The phylogenetic position of P. nandai within Eoacanthocephala was generated to assess the molecular characterization based on 18S and ITS1-5.8S-ITS2 ribosomal DNA sequences. Maximum likelihood and Bayesian inference analyses placed P. nandai in a clade with other Pallisentis species under the family Quadrigyridae. This is the first report based on molecular evidence for P. nandai.
Topics: Acanthocephala; Animals; Bayes Theorem; Female; Fish Diseases; Helminthiasis, Animal; India; Male; Microscopy, Electron, Scanning; Phylogeny
PubMed: 33504379
DOI: 10.1017/S0022149X20001005 -
Annals of Parasitology 2022The leaping mullet Chelon saliens is one of the economically significant fish species and the revealing its parasite fauna in relation with some ecological and host...
The leaping mullet Chelon saliens is one of the economically significant fish species and the revealing its parasite fauna in relation with some ecological and host related factors will provide new data for our current knowledge. A total of 165 leaping mullet were collected from Sinop coasts of the Black Sea in the period from September 2015 to August 2016 and investigated for parasites. Eleven parasite species including Myxobolus parvus, Myxobolus sp., Sphaerospora mugilis (Myxozoa), Ligophorus szidati, Solostamenides mugilis (Monogenea), Schikhobalotrema sparisomae, Saccocoelium tensum, Saccocoelium obesum (Digenea), Hysterothylacium aduncum (Nematoda), Neoechinorhynchus sp. (Acanthocephala) and Ergasilus lizae (Copepoda) have been identified. The overall infection prevalence, mean intensity and mean abundance values were 65.5%, 26.2 and 17.2, respectively. The overall infection prevalence was dominated by L. szidati, followed by M. parvus and Digenea-group. On the other hand, the overall mean intensity values were dominated by Digenea-group, followed by L. szidati and E. lizae, respectively, while the mean abundance values were dominated by L. szidati, followed by Digenea-group and E. lizae. The infection indices of all identified parasites were also calculated in relation with length classes and sex of fish as well as season and the differences were evaluated statistically. Seasonally significant differences in the infection prevalence and mean abundance were found for Digenea-group, Ligophorus szidati and Neoechinorhynchus sp. These differences were also significant in the length classes of Digenea-group and Ligophorus szidati. This study is the first investigation on seasonal and host related dynamics of parasites of C. saliens in the southern coasts of the Black Sea and all investigated factors were found to influence the infection indices of dominating parasite species.
Topics: Animals; Black Sea; Copepoda; Fish Diseases; Fishes; Myxobolus; Parasites; Polycarboxylate Cement; Seasons; Smegmamorpha; Trematoda
PubMed: 35810385
DOI: 10.17420/ap6802.441 -
Parasitology Jan 2024Acanthocephalans of the order Polymorphida mainly parasitic in birds and mammals, are of veterinary, medical and economic importance. However, the evolutionary...
Characterization of the complete mitochondrial genomes of the zoonotic parasites and (Acanthocephala: Polymorphida) and the molecular phylogeny of the order Polymorphida.
Acanthocephalans of the order Polymorphida mainly parasitic in birds and mammals, are of veterinary, medical and economic importance. However, the evolutionary relationships of its 3 families (Centrorhynchidae, Polymorphidae and Plagiorhynchidae) remain under debate. Additionally, some species of Polymorphida (i.e. spp. and spp.) are recognized as zoonotic parasites, associated with human acanthocephaliasis, but the mitochondrial genomes for representatives of and have not been reported so far. In the present study, the complete mitochondrial genomes and (Acanthocephala: Polymorphidae) are reported for the first time, which are 14 296 and 14 241 bp in length, respectively, and both contain 36 genes [including 12 PCGs, 22 tRNA genes and 2 rRNA genes] and 2 non-coding regions ( and ). The gene arrangement of some tRNAs in the mitogenomes of and differs from that found in all other acanthocephalans, except . Phylogenetic results based on concatenated amino acid (AA) sequences of the 12 protein-coding genes (PCGs) strongly supported that the family Polymorphidae is a sister to the Centrorhynchidae rather than the Plagiorhynchidae, and also confirmed the sister relationship of the genera and in the Polymorphidae based on the mitogenomic data for the first time. Our present findings further clarified the phylogenetic relationships of the 3 families Plagiorhynchidae, Centrorhynchidae and Polymorphidae, enriched the mitogenome data of the phylum Acanthocephala (especially the order Polymorphida), and provided the resource of genetic data for diagnosing these 2 pathogenic parasites of human acanthocephaliasis.
Topics: Animals; Humans; Acanthocephala; Phylogeny; Genome, Mitochondrial; Parasites; Birds; Mammals
PubMed: 37955106
DOI: 10.1017/S0031182023001099 -
The Journal of Parasitology Mar 2023This study reports a new case of acanthocephalan (thorny-headed worm) eggs in a coprolite from Bonneville Estates Rockshelter in eastern Nevada and uses archaeological... (Review)
Review
This study reports a new case of acanthocephalan (thorny-headed worm) eggs in a coprolite from Bonneville Estates Rockshelter in eastern Nevada and uses archaeological and ethnographic data to better understand long-term relationships between people and acanthocephalans. Acanthocephalans are parasitic worms that use arthropods as intermediate hosts in their multi-host life cycles. Though acanthocephaliasis is rare among humans today, cases have increased in the last decade, and the discovery of acanthocephalan eggs in coprolites from archaeological sites in the Great Basin suggests a deep, shared history. At Bonneville Estates Rockshelter, 9 acanthocephalan eggs were recovered using a modified rehydration-homogenization-micro-sieving protocol on a coprolite that was radiocarbon dated to 6,040 ± 60 14C BP (7,160-6,730 cal BP), pushing back the oldest evidence of human acanthocephalan infection by 3 millennia. Researchers have proposed that the paleoepidemiology of acanthocephalans may relate to subsistence practices due to overlap in locations of infection and areas where insects are part of traditional foodways. This paper considers the paleoepidemiology of acanthocephalan infection through the first combined review of paleoparasitological, ethnographic, and archaeological records in western North America. Ethnographic and archaeological records support the hypothesis that archaeological cases of human acanthocephaliasis may be linked to entomophagy. Additional parasitological analyses are advised to determine whether this distribution is the result of dietary practices, host ecology, taphonomic issues, sampling biases, or a combination of factors.
Topics: Animals; Humans; Acanthocephala; Arthropods; Helminthiasis; Nevada
PubMed: 36930699
DOI: 10.1645/22-92 -
Diseases of Aquatic Organisms May 2022Invasive non-native amphipods (Crustacea) are becoming a model system in which to explore the impact and diversity of invasive parasites-parasites that are carried along...
Invasive non-native amphipods (Crustacea) are becoming a model system in which to explore the impact and diversity of invasive parasites-parasites that are carried along an invasion route with their hosts. Gammarus varsoviensis is a freshwater amphipod species that has a recently explored invasion history. We provide a histopathological survey for a putatively invasive non-native population of this amphipod, identifying 8 symbiotic groups: Acanthocephala, Rotifera, Digenea, ciliated protozoa, Haplosporidia, Microsporidia, 'Candidatus Aquirickettsiella', and a putative nudivirus, at various prevalence. Our survey indicates that the parasites have no sex bias and that each has the potential to be carried in either sex along an invasion route. We discuss the pathology and prevalence of the above symbiotic groups and whether those that are parasitic may pose a risk if G. varsoviensis were to carry them to novel locations.
Topics: Acanthocephala; Amphipoda; Animals; Host-Parasite Interactions; Microsporidia; Parasites
PubMed: 35510820
DOI: 10.3354/dao03658 -
The Journal of Parasitology Feb 2020Soota and Bhattacharya, 1981 , has remained unknown since its original incomplete description from 2 male specimens collected from the flat needlefish Valenciennes...
Soota and Bhattacharya, 1981 , has remained unknown since its original incomplete description from 2 male specimens collected from the flat needlefish Valenciennes (Belonidae) off Trivandrum, Kerala, India. Recent collections of fishes along the Pacific coast of Vietnam in 2016 and 2017 produced many specimens of the same species from the striped bonito Temminck and Schlegel (Scombridae) off the southern Pacific coast of Vietnam at Nha Trang. We describe females for the first time, assign a female allotype status, and provide an expanded description of males from a larger collection completing missing information on hooks and hook roots, receptacle, lemnisci, cement glands, Saefftigen's pouch, and trunk spines. Specimens of characteristically have no dorsal spines in the posterior field of trunk spines and a long proboscis with 36-48 dorso-ventrally differentiated proboscis hooks per row becoming progressively smaller posteriorly then increasing in size near the posterior end to a maximum at the posterior-most ring. Trunk, testes, and lemnisci in our specimens were considerably larger than those reported in the original description, but the proboscis was relatively smaller. The females had long reproductive system and corrugated elliptic eggs without polar prolongation of fertilization membrane. Energy Dispersive X-ray Analysis (EDXA) demonstrates high levels of calcium and phosphorus in large gallium cut hooks and high levels of sulfur in tip cuts of large and small hooks and in spines. This EDXA pattern is a characteristic fingerprint of . The molecular profile of is described from rDNA and genes, and phylogenetic relationships with most closely related species are discussed.
Topics: Acanthocephala; Algorithms; Animals; Bayes Theorem; Beloniformes; Female; Fish Diseases; Fishes; Gallium; Helminthiasis, Animal; Likelihood Functions; Male; Microscopy, Electron, Scanning; Pacific Ocean; Phylogeny; Spectrometry, X-Ray Emission; Vietnam
PubMed: 31995719
DOI: No ID Found -
Acta Parasitologica Sep 2022To confirm the identity of Longicollum edmondsi Golvan, 1969, Pomphorhynchidae Yamaguti, 1939, from Australia.
PURPOSE
To confirm the identity of Longicollum edmondsi Golvan, 1969, Pomphorhynchidae Yamaguti, 1939, from Australia.
METHODS
All the relevant specimens registered in Australian museums were examined. Those held as permanent slide preparations were examined directly and those stored in 70% ethanol were examined as temporary wet mounts, after clearing in lactophenol, using an Olympus BH-2 microscope with differential interference optics. Measurements were made with an eyepiece micrometer and figures drawn using a drawing tube.
RESULTS
All the material registered as either Longicollum edmondsi or Paralongicollum sp. was determined to be Paralongicollum edmondsi (Golvan, 1969) comb. nov. based, amongst other characters, on the morphology of the neck.
DISCUSSION
The significance of known host species of P. edmondsi and their geographical distribution around the Australian coast was analysed. The geographical distribution of the genus Paralongicollum, Amin, Bauer & Siderov, 1991, across the Indo Pacific was compared to that of the acanthocephalan genus Sclerocollum Schmidt & Paperna, 1978.
Topics: Acanthocephala; Animals; Ascomycota; Australia; Host Specificity; Microscopy
PubMed: 35616830
DOI: 10.1007/s11686-022-00565-x