Strigeidae Dotaz Zobrazit nápovědu
Strigeidae Railliet, 1919 are digenean parasites of birds and mammals that are characteristic by their cup-shaped forebody and bilobed holdfast organ. Despite that the family is taxonomically unsettled, particularly due to a very limited number of visible autapomorphic identification features, molecular phylogenetics have never been applied to analyze the relationships among European members of Strigeidae except for the genus Ichthyocotylurus. Here, we analyze the Strigeidae found during the examination of Czech birds performed from 1962 to 2017, and we provide comparative measurements and host spectra, including prevalence and intensity; we also provide and analyze sequences of four DNA loci of 12 of the Strigeidae species. We suggest the reclassification of Parastrigea robusta Szidat, 1928 as Strigea robusta (Szidat, 1928) Heneberg and Sitko, 2018 comb. n. The genera Strigea Abildgaard, 1790 and Parastrigea Szidat, 1928 appear paraphyletic, and morphological diagnostic features of genera within Strigeini Dubois, 1936 are invalid. The mute swan Cygnus olor hosts two Cotylurus spp., Cotylurus syrius Dubois, 1934 and a second species with molecular identification features shared in part with Cotylurus cornutus (Rudolphi, 1808) and Cotylurus gallinulae Lutz, 1928. New host records are provided for seven species. Analyses of non-European genera of the Strigeidae are needed to provide an updated key to Strigeini.
- MeSH
- fylogeneze MeSH
- hostitelská specificita MeSH
- infekce červy třídy Trematoda epidemiologie parazitologie veterinární MeSH
- nemoci ptáků epidemiologie parazitologie MeSH
- prevalence MeSH
- protozoální DNA analýza MeSH
- protozoální proteiny analýza MeSH
- ptáci * MeSH
- sekvenční analýza DNA MeSH
- Trematoda anatomie a histologie klasifikace genetika fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
- MeSH
- Trematoda fyziologie klasifikace růst a vývoj MeSH
- Geografické názvy
- Československo MeSH
BACKGROUND: Despite their complex life-cycles involving various types of hosts and free-living stages, digenean trematodes are becoming recurrent model systems. The infection and penetration strategy of the larval stages, i.e. cercariae, into the fish host is poorly understood and information regarding their entry portals is not well-known for most species. Cardiocephaloides longicollis (Rudolphi, 1819) Dubois, 1982 (Digenea, Strigeidae) uses the gilthead seabream (Sparus aurata L.), an important marine fish in Mediterranean aquaculture, as a second intermediate host, where they encyst in the brain as metacercariae. Labelling the cercariae with in vivo fluorescent dyes helped us to track their entry into the fish, revealing the penetration pattern that C. longicollis uses to infect S. aurata. METHODS: Two different fluorescent dyes were used: carboxyfluorescein diacetate succinimidyl ester (CFSE) and Hoechst 33342 (NB). Three ascending concentrations of each dye were tested to detect any effect on labelled cercarial performance, by recording their survival for the first 5 h post-labelling (hpl) and 24 hpl, as well as their activity for 5 hpl. Labelled cercariae were used to track the penetration points into fish, and cercarial infectivity and later encystment were analysed by recording brain-encysted metacercariae in fish infected with labelled and control cercariae after 20 days of infection. RESULTS: Although the different dye concentrations showed diverse effects on both survival and activity, intermediate doses of CFSE did not show any short-term effect on survival, permitting a brighter and longer recognition of cercariae on the host body surface. Therefore, CFSE helped to determine the penetration points of C. longicollis into the fish, denoting their aggregation on the head, eye and gills region, as well as on the dorsal fin and the lower side. Only CFSE-labelled cercariae showed a decreased number of encysted metacercariae when compared to control. CONCLUSIONS: Our study suggests that CFSE is an adequate labelling method for short-term in vivo studies, whereas NB would better suit in vivo studies on long-term performance. Cardiocephaloides longicollis cercariae seem to be attracted to areas near to the brain or those that are likely to be connected to migration routes to neuronal canals.
- MeSH
- benzimidazoly MeSH
- cerkárie MeSH
- fluoresceiny MeSH
- fluorescenční barviva * MeSH
- infekce červy třídy Trematoda přenos veterinární MeSH
- interakce hostitele a parazita * MeSH
- larva MeSH
- metacerkárie MeSH
- mořan zlatý parazitologie MeSH
- nemoci ryb parazitologie MeSH
- stadia vývoje MeSH
- sukcinimidy MeSH
- Trematoda růst a vývoj fyziologie MeSH
- vodní hospodářství MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Factors that drive parasite specificity and differences in infection dynamics among alternative host species are important for ecology and evolution of host-parasite interactions, but still often poorly known in natural systems. Here, we investigated spatiotemporal dynamics of infection, host susceptibility and parasite-induced changes in host phenotype in a rarely explored host-parasite system, the Australapatemon sp. trematode infecting two sympatric species of freshwater leeches, Erpobdella octoculata and Helobdella stagnalis. We show significant variation in infection abundance between the host species in both space and time. Using experimental infections, we also show that most of this variation likely comes from interspecific differences in exposure rather than susceptibility. Moreover, we demonstrate that the hiding behaviour of E. octoculata, but not that of H. stagnalis, was impaired by the infection irrespective of the parasite abundance. This may increase susceptibility of E. octoculata to predation by the final avian host. We conclude that differences in patterns of infection and in behavioural alterations among alternative sympatric host species may arise in narrow spatial scales, which emphasises the importance of local infection and transmission dynamics for parasite life cycles.
South African clinids are a major component of the temperate intertidal regions that are also known to participate in life cycles and transmission of several groups of parasites. However, the knowledge of trematode diversity of these fishes is incomplete. In this study, two species of Clinus Cuvier, the super klipfish Clinus superciliosus (Linnaeus) and the bluntnose klipfish Clinus cottoides Valenciennes, were collected from six localities along the South African coast and examined for the presence of trematodes. Metacercariae of Cardiocephaloides Sudarikov, 1959 were found in the eye vitreous humour and brain of C. superciliosus and in the eye vitreous humour of C. cottoides. Detailed analyses integrating morphological and molecular sequence data (28S rDNA, ITS2 rDNA-region, and COI mtDNA) revealed that these belong to two species, Cardiocephaloides physalis (Lutz, 1926) and an unknown species of Cardiocephaloides. This study provides the first report of clinid fishes serving as intermediate hosts for trematodes, reveals that the diversity of Cardiocephaloides in South Africa is higher than previously recorded, and highlights the need for further research to elucidate the life cycles of these trematode species. The broad geographical distribution of Cardiocephaloides spp. was confirmed in the present study based on molecular sequence data. The host-parasite interactions between clinid fishes and metacercariae of Cardiocephaloides are yet to be explored.
- MeSH
- fylogeneze MeSH
- geny helmintů MeSH
- infekce červy třídy Trematoda parazitologie MeSH
- interakce hostitele a parazita MeSH
- metacerkárie anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- nemoci ryb parazitologie MeSH
- Perciformes parazitologie MeSH
- ribozomální DNA genetika MeSH
- ryby parazitologie MeSH
- stadia vývoje MeSH
- Trematoda * anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Jihoafrická republika MeSH
The functional ultrastructure and embryonic development of miracidia in naturally released eggs of the trematode Cardiocephaloides longicollis were studied using light and transmission electron microscopy. This species has operculated eggs and embryogenesis occurs in the marine environment before an actively infecting ciliated miracidium hatches. Six different developmental stages were identified. The lack of pores in the eggshell indicates its impermeability and the miracidium's dependency on glycogen nutritive reserves, contained in numerous vitellocytes in early embryos. As the development advances, these merge into larger vitelline vacuoles that encircle the miracidium and may aid its hatching. Tissue and primary organ differentiation were observed in advanced stages, i.e., terebratorium, glands, cerebral ganglion, peripheral sensory endings, and eyespots. The anterior part of the body contains a single apical and paired lateral glands, as well as two types of sensory endings, which permit location, adhesion, and penetration of the host. No previous studies describe the embryonic development and ultrastructure of miracidia in strigeids, however, some of the structural features shared with other, well described species with unknown life cycles are emphasised. This study highlights that ultrastructural data have to be interpreted in relation to parasite biology to understand the structural requirements of specific parasite strategies.
A new strigeid digenean, Strigea meridionalis sp. n., is described from the small intestine of the savanna hawk, Buteogallus meridionalis (Latham) (Aves: Accipitridae), from Formosa Province, Argentina. This species is characterised by the absence of a neck region in the hindbody, the presence of entire testes, a copulatory bursa with a membranous fold originated from the muscular ring (Ringnapf) and by the arrangement of vitelline follicles in the forebody. Other two strigeid species collected from the savanna hawk, Strigea elliptica (Brandes, 1888) and Strigea microbursa Pearson et Dubois, 1985, are described and illustrated. Strigea microbursa is reported for the first time from the Neotropical Region and B. meridionalis represents a new host record for S. elliptica. These findings allow us to increase the knowledge of these species, adding new metric and morphological data. A key to the species of the Neotropical Strigea Abildgaard, 1790 is presented including data on their geographical distribution.
During a survey of birds from Argentina, two species of Digenea, one of them new, were found parasitizing the great antshrike, Taraba major (Vieillot) (Aves: Thamnophilidae). The strigeid, Strigea orbiculata sp. n. is characterized by having a body plump, a copulatory bursa without a membraneous fold ('Ringnapf'), entire testes, eggs with miracidia with eye-spots, by the arrangement of vitelline follicles in the forebody, which are densely distributed from its anterior edge, and by the absence of a neck region in the hindbody. Among the known Neotropical species of Strigea Abildgaard, 1790, only five share with Strigea orbiculata sp. n. the body shape and the distribution ofvitelline follicles in the forebody: Strigea caluri Dubois, 1962, S. elliptica (Brandes, 1888), S. inflecta Lunaschi et Drago, 2012, S. nugax Szidat, 1928 and S. sphaerocephala (Westrumb, 1823 nec Brandes 1888). However, S. caluri can be easily distinguished by having a membraneous fold in the copulatory bursa originated from 'Ringnapf', and multilobed testes. Strigea elliptica differs mainly by having a well developed 'Ringnapf' and the remaining species differ principally by metrical characters. The dicrocoeliid, Lyperosomum oswaldoi (Travassos, 1919) is reported for the first time from Argentina and T. major represents its new definitive host. The host specificity ofNeotropical Strigea spp. is discussed and an updated list of records of their hosts is provided.
- MeSH
- druhová specificita MeSH
- infekce červy třídy Trematoda parazitologie veterinární MeSH
- nemoci ptáků epidemiologie parazitologie MeSH
- Passeriformes * MeSH
- Trematoda anatomie a histologie klasifikace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Argentina MeSH
Trematodes of the order Diplostomida are well known as serious pathogens of man, and both farm and wild animals; members of the genus Schistosoma (Schistosomatidae) are responsible for human schistosomosis (schistosomiasis) affecting more than 200 million people in tropical and subtropical countries, and infections of mammals and birds by animal schistosomes are of great veterinary importance. The order Diplostomida is also rich in species parasitizing other major taxa of vertebrates. The "Aporocotylidae" sensu lato are pathogenic in fish, "Spirorchiidae" sensu lato in reptiles. All these flukes have two-host life cycles, with asexually reproducing larvae usually in mollusks and occasionally in annelids, and adults usually live in the blood vessels of their vertebrate hosts. Pathology is frequently associated with inflammatory reactions to eggs trapped in various tissues/organs. On the other hand, the representatives of Diplostomidae and Strigeidae have three- or four-host life cycles in which vertebrates often serve not only as definitive but also as intermediate or paratenic hosts. Pathology is usually associated with migration of metacercariae and mesocercariae within the host tissues. The impact of these trematode infections on both farm and wild animals may be significant.