Interplay between conserved host specificity and occasional host switches is an important process determining the evolution of host-parasite systems. Here, we address the dynamics of host switches at the population level in rodent-associated Eimeria. Focusing mainly on two ecologically similar host groups, Murinae and Arvicolinae, we show that the Eimeria infecting those hosts form a complex system of many genetic lineages with different host specificities. The broad geographic distribution of lineages indicates that they are well-established genetic forms which retained their host specificities while spreading across large geographic areas. We also demonstrate that genetic structure is only partially reflected by morphological traits.
- Klíčová slova
- Arvicolinae, Coccidia, Coevolution, Host specificity, Murinae, Phylogeny,
- MeSH
- Arvicolinae MeSH
- Eimeria * MeSH
- fylogeneze MeSH
- hostitelská specificita MeSH
- interakce hostitele a parazita MeSH
- lidé MeSH
- Murinae MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The Javan ferret-badger Melogale orientalis (Carnivora: Mustelidae: Helictidinae) is a small carnivore endemic to Indonesia. In the family Mustelidae, 10 Eimeria, 12 Cystoisopora, one Isospora, and one Hammondia species are known, but no eimeriid coccidia has been yet described in the subfamily Helictinidae (ferret badgers). Coproscopic examination of Javan ferret-badgers imported into the Czech Republic revealed the presence of coccidian oocysts. Sporulated oocysts differ from other Eimeria known in the family Mustelidae by their small size (12.4-16.1 × 10.4-13.4 μm) and ovoidal shape. Morphological data and phylogenetic analyses of 18S rRNA and COI genes indicated a new species of Eimeria found in faecal samples of Javan ferret badgers. The species is described as E. melogale n. sp.
- Klíčová slova
- Carnivora, Coccidia, Mustelidae, Phylogeny,
- MeSH
- druhová specificita MeSH
- Eimeria klasifikace cytologie genetika MeSH
- feces parazitologie MeSH
- fylogeneze * MeSH
- Mustelidae parazitologie MeSH
- oocysty cytologie MeSH
- RNA ribozomální 18S genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- RNA ribozomální 18S MeSH
Detection and quantification of coccidia in studies of wildlife can be challenging. Therefore, prevalence of coccidia is often not assessed at the parasite species level in non-livestock animals. Parasite species - specific prevalences are especially important when studying evolutionary questions in wild populations. We tested whether increased host population density increases prevalence of individual Eimeria species at the farm level, as predicted by epidemiological theory. We studied free-living commensal populations of the house mouse (Mus musculus) in Germany, and established a strategy to detect and quantify Eimeria infections. We show that a novel diagnostic primer targeting the apicoplast genome (Ap5) and coprological assessment after flotation provide complementary detection results increasing sensitivity. Genotyping PCRs confirm detection in a subset of samples and cross-validation of different PCR markers does not indicate bias towards a particular parasite species in genotyping. We were able to detect double infections and to determine the preferred niche of each parasite species along the distal-proximal axis of the intestine. Parasite genotyping from tissue samples provides additional indication for the absence of species bias in genotyping amplifications. Three Eimeria species were found infecting house mice at different prevalences: Eimeria ferrisi (16.7%; 95% CI 13.2-20.7), E. falciformis (4.2%; 95% CI 2.6-6.8) and E. vermiformis (1.9%; 95% CI 0.9-3.8). We also find that mice in dense populations are more likely to be infected with E. falciformis and E. ferrisi. We provide methods for the assessment of prevalences of coccidia at the species level in rodent systems. We show and discuss how such data can help to test hypotheses in ecology, evolution and epidemiology on a species level.
- Klíčová slova
- Coccidia, Diagnostic PCR, Eimeria, House mice, Species-specific prevalence, qPCR,
- Publikační typ
- časopisecké články MeSH
Using a combination of morphological and molecular data, we describe a new apicomplexan parasite, Isospora svecica sp. n., from the white-spotted bluethroat, Luscinia svecica cyanecula, from the Czech Republic. Oocysts were found in its intestinal tract. Sporulation was exogenous and took 1-3 days. The oocysts were slightly ellipsoidal, of average size 26.17 × 20.33 μm, with a smooth bilayered wall. Micropyle, oocyst residuum, and polar granules were absent. Sporocysts were bottle-shaped, of an average size of 18.82 × 8.82 μm, with a thin, colourless wall. A conspicuous knob-like Stieda body was present. Substieda body was barely visible. Sporocyst residuum was present in the form of granules of various sizes. Sporozoites were banana-shaped and contained large anterior and small posterior refractile bodies. Partial DNA sequences of three genes were obtained from oocysts of Isospora svecica sp. n., being most closely related to other isosporans described from passerines. Little is known about the parasites of the avian family Muscicapidae, including coccidia, a highly prevalent parasitic protist group in all vertebrate classes. Only six species of the genus Isospora have so far been described in Muscicapidae, together with several "Isospora sp." that in fact most likely represent Isospora lacazei. The newly described Isospora svecica sp. n. differs morphologically from other coccidia reported from muscicapid birds, and represents the first coccidian species described from Luscinia svecica.
- Klíčová slova
- Aves, Coccidia, Isospora, Morphology, Muscicapidae, Phylogeny,
- MeSH
- Isospora klasifikace cytologie genetika růst a vývoj MeSH
- izosporóza parazitologie veterinární MeSH
- oocysty klasifikace cytologie genetika růst a vývoj MeSH
- Passeriformes parazitologie MeSH
- protozoální geny genetika MeSH
- sporozoiti klasifikace cytologie genetika růst a vývoj MeSH
- střeva parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Intranuclear coccidiosis of testudines (known as TINC) is an emerging disease in chelonians. Although endogenous stages were repeatedly detected in various tissues, attempts to find the oocysts in faeces failed, leaving the question of the transmission and classification of the causative agent of TINC unresolved. We recorded small spherical oocysts (∼6-7 μm in diameter) of an eimeriid coccidium in faeces of a leopard tortoise (Stigmochelys pardalis). Sporulated oocysts were used for the experimental oral inoculation of juvenile coccidia-free tortoises representing 5 species (S. pardalis, Testudo graeca, T. hermanni, T. horsfieldii, and Geochelone sulcata). The oocysts' association with TINC was confirmed based on clinical signs, histopathological findings of intranuclear endogenous stages of the coccidium in many organs (including intestine), and by the partial 18S rDNA sequence analysis of the DNA isolated from organs of the experimentally infected animals and from a single naturally infected as well as from all experimentally infected tortoises. Breeding colonies of chelonians should be screened for this pathogen in order to prevent its further spread and unwanted introduction into endangered free-ranging chelonian populations.
- Klíčová slova
- Eimeriid coccidium, TINC, Testudines,
- MeSH
- Eimeriidae klasifikace genetika izolace a purifikace fyziologie MeSH
- feces parazitologie MeSH
- kokcidióza parazitologie prevence a kontrola přenos veterinární MeSH
- oocysty MeSH
- parazitární nemoci u zvířat parazitologie prevence a kontrola přenos MeSH
- RNA ribozomální 18S genetika MeSH
- želvy parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- RNA ribozomální 18S MeSH
Coccidia of the genus Isospora, their origin, taxonomy, and host specificity have been discussed for many years. The crucial point in question being the division of the genus, based on distinct evolutionary history and the presence/absence of the Stieda body, into the genera Isospora (Eimeriidae) parasitizing mainly birds and reptiles, and Cystoisospora (Sarcocystidae) parasitizing mammals. The description of the majority of Isospora species from rodents is based solely on the oocysts found in their faeces. Some of them have been described with the presence of the Stieda body, some without it, and, simultaneously, for all the described species the molecular data are entirely lacking. This study reveals the origin of isosporan oocysts found in faeces of bank voles based on morphological analyses, phylogenetic analyses, and experimental infections. Morphological analyses showed the presence of the Stieda body complex on sporocysts. Phylogenetic analyses demonstrated close phylogenetic relationships between Isospora from bank voles and avian isosporans. Experimental inoculations of bank voles with sporulated oocysts of Isospora did not result in the production of unsporulated oocysts. Hence, these organisms should be considered pseudoparasites of the bank voles/rodents (probably originating from avian Isospora species).
- Klíčová slova
- Cystoisospora, Isospora, coccidian, pseudoparasite., rodent, vole,
- MeSH
- Arvicolinae parazitologie MeSH
- feces parazitologie MeSH
- fylogeneze MeSH
- Isospora cytologie izolace a purifikace fyziologie MeSH
- oocysty cytologie izolace a purifikace fyziologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Philippine tarsier (Tarsius syrichta) is a small nocturnal primate from the Philippines. Little is known about tarsier parasites, including coccidia (Apicomplexa: Eimeriidae), a highly prevalent parasitic protist group in all vertebrate classes. Only 7 valid species of the genus Eimeria, seven species of Isospora and 5 species of Cyclospora have been described in Primates. This study extends the number of coccidia known in primates by two new species obtained from faeces of Philippine tarsiers from Bohol Island. The newly described Eimeria syrichta n. sp. and Eimeria boholensis n. sp. differ morphologically from each other as well as from other coccidia reported from primates. Partial DNA sequences of three genes were obtained from oocysts of E. syrichta n. sp. and E. boholensis n. sp., and formed clusters according to their host specificity; however, there are no other sequentional data of coccidia from primates, except for the genus Cyclospora, which clusters inside the chicken eimerians, and Cystoisospora belli, which is phylogenetically related to Sarcocystidae. More molecular data on coccidia infecting primates are needed for further discussion.
- Klíčová slova
- 18S rDNA, COI, Coccidia, ORF 470, Phylogeny, Primates,
- MeSH
- druhová specificita MeSH
- Eimeria klasifikace fyziologie MeSH
- fylogeneze * MeSH
- hostitelská specificita MeSH
- protozoální DNA genetika MeSH
- Tarsiidae parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Filipíny MeSH
- Názvy látek
- protozoální DNA MeSH
Recent studies show that host switching is much more frequent than originally believed and constitutes an important driver in evolution of host-parasite associations. However, its frequency and ecological mechanisms at the population level have been rarely investigated. We address this issue by analyzing phylogeny and population genetics of an extensive sample, from a broad geographic area, for commonly occurring parasites of the genus Eimeria within the abundant rodent genera Apodemus, Microtus and Myodes, using two molecular markers. At the most basal level, we demonstrate polyphyletic arrangement, i.e. multiple origin, of the rodent-specific clusters within the Eimeria phylogeny, and strong genetic/phylogenetic structure within these lineages determined at least partially by specificities to different host groups. However, a novel and the most important observation is a repeated occurrence of host switches among closely related genetic lineages which may become rapidly fixed. Within the studied model, this phenomenon applies particularly to the switches between the eimerians from Apodemus flavicollis/Apodemus sylvaticus and Apodemus agrarius groups. We show that genetic differentiation and isolation between A. flavicollis/A. sylvaticus and A. agrarius faunas is a secondary recent event and does not reflect host-parasite coevolutionary history. Rather, it provides an example of rapid ecology-based differentiation in the parasite population.
- Klíčová slova
- Coevolution, Ecological fitting, Host specificity, Host switching, Parasite, Rodent,
- MeSH
- biodiverzita * MeSH
- časové faktory MeSH
- Coccidia klasifikace genetika fyziologie MeSH
- fylogeneze MeSH
- haplotypy genetika MeSH
- hostitelská specificita * MeSH
- interakce hostitele a parazita * genetika MeSH
- Murinae parazitologie MeSH
- populační genetika MeSH
- zeměpis MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH