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1.
Parasitol Res ; 123(5): 206, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713306

RESUMO

The Australian skink Egernia stokesii had been recognised as a host of two species of Plasmodium, Plasmodium mackerrasae and P. circularis; nevertheless, molecular data are available for only a single haemosporidian species of this host. Its sequences are labelled as "Plasmodium sp." or "Plasmodium mackerrasae", but morphological characteristics of this isolate are unavailable. Phylogenetic analyses of these sequences placed them into the clade of the genus Haemocystidium. In this study, blood samples of six E. stokesii were analysed by both, molecular and microscopic methods to clarify the haemosporidia of this lizard. Application of these approaches offered discordant results. Whereas sequence analysis clustered our isolates with lizard species of Haemocystidium, morphology of blood stages is more akin to Plasmodium than Haemocystidium. However, limited sampling, indistinguishable nuclei/merozoites and risk of possible hidden presence of mixed infection prevent reliable species identification of detected parasites or their description as new species of Haemocystidium.


Assuntos
Haemosporida , Lagartos , Filogenia , Animais , Lagartos/parasitologia , Austrália , Haemosporida/genética , Haemosporida/classificação , Haemosporida/isolamento & purificação , DNA de Protozoário/genética , Análise de Sequência de DNA , Dados de Sequência Molecular , Análise por Conglomerados , DNA Ribossômico/genética , Microscopia , Sangue/parasitologia , RNA Ribossômico 18S/genética , Infecções Protozoárias em Animais/parasitologia
2.
Emerg Infect Dis ; 28(4): 893-895, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35318933

RESUMO

We collected 1,671 Dermacentor reticulatus ticks from 17 locations in the Czech Republic, Slovakia, and Hungary. We found 47.9% overall prevalence of Rickettsia species in ticks over all locations. Sequence analysis confirmed that all tested samples belonged to R. raoultii, the causative agent of tick-borne lymphadenopathy.


Assuntos
Dermacentor , Ixodes , Rickettsia , Animais , Dermacentor/microbiologia , Europa (Continente) , Ixodes/microbiologia , Prevalência , Rickettsia/genética
3.
Emerg Infect Dis ; 25(9): 1738-1741, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31441762

RESUMO

Using long-term data on incidences of Lyme disease and tickborne encephalitis, we showed that the dynamics of both diseases in central Europe are predictable from rodent host densities and climate indices. Our approach offers a simple and effective tool to predict a tickborne disease risk 1 year in advance.


Assuntos
Clima , Ratos/fisiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Reservatórios de Doenças , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/etiologia , Europa Oriental/epidemiologia , Incidência , Ixodes , Doença de Lyme/epidemiologia , Doença de Lyme/etiologia , Fatores de Risco , Doenças Transmitidas por Carrapatos/etiologia
4.
Parasitology ; 146(13): 1690-1698, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31391126

RESUMO

Apicomplexan haemoparasites of the genera Schellackia Reichenow, 1919, and Karyolysus Labbé, 1894, seem to be common in lizards and widespread across the world. For decades, their identification has been based on morphological descriptions and life cycle patterns, with molecular characterizations, applied only recently. We used molecular characterization to confirm the identification of haemoparasites detected by microscopy in blood smears of Lacerta schreiberi Bedriaga, 1878, a lizard of the Iberian Peninsula. Since blood samples other than blood smears were not available from the studied lizards, 264 engorged ticks Ixodes ricinus (Linneaus, 1758) collected from them were used as an alternative non-invasive source of haemoparasite DNA for molecular genetic analyses. Of the 48 blood smears microscopically examined, 31 were positive for blood parasites (64.6% prevalence). We identified trophozoites and gamonts similar to Karyolysus lacazei (Labbé, 1894) (24/48; 50%) and Schellackia-like sporozoites (20/48; 41.7%). Mixed infections with both species occurred in 13 blood smears (27.1%). Sequence data were obtained for both parasites from engorged ticks. Phylogenetic analyses placed our unique haemogregarine sequence within the Karyolysus clade, nevertheless, within substantial polytomy. Thus, according to its morphology and effect on the host cell, we refer to this haemogregarine as Karyolysus cf. lacazei. Besides the Schellackia sequences being identical to a previously identified haplotype, we also obtained sequences of three new closely related haplotypes.


Assuntos
Coccidiose/veterinária , Eucoccidiida/classificação , Variação Genética , Ixodes/parasitologia , Lagartos/parasitologia , Animais , Coccidiose/sangue , Coccidiose/parasitologia , DNA de Protozoário/genética , Haplótipos , Filogenia , Análise de Sequência de DNA , Esporozoítos/genética , Trofozoítos/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-28906256

RESUMO

The distribution, variability and host specificity of species of Babesia Starcovici, 1893 were studied in questing ticks collected on the northwestern edge of the Pannonian Basin in the south-easternmost part of the Czech Republic and in western Slovakia. The area is characterised by relatively natural floodplain habitats and the sympatric occurrence of three tick species possessing wide host spectra, namely Ixodes ricinus (Linnaeus), Dermacentor reticulatus (Fabricius) and Haemaphysalis concinna Koch. Analysis was carried out on 1,408 I. ricinus, 2,999 D. reticulatus and 150 H. concinna altogether, collected from 59 localities. We documented the presence of Babesia spp. not only in I. ricinus but also in H. concinna in the Czech Republic. Two isolates from I. ricinus were classified as B. venatorum Herwaldt, Cacciò, Gherlinzoni, Aspöck, Slemenda, Piccaluga, Martinelli, Edelhofer, Hollenstein, Poletti, Pampiglione, Löschenberger, Tura et Pieniazek, 2003 (formerly determined as Babesia sp. EU1), which is a zoonotic parasite and can cause human babesiosis. The rest of our amplicons were very similar to B. canis (Piana et Galli-Valerio, 1895), which is usually transmitted by D. reticulatus. Despite the huge amount of examined samples, all D. reticulatus ticks were Babesia-free. Due to this finding, we did not consider our obtained isolates to be B. canis, but other closely related species possessing a similar sequence of the studied portion of 18S rDNA. Although this genetic marker is most frequently used in PCR-based diagnostic methods of babesias, its low variability compromises its reliability in studies based only on this marker.


Assuntos
Vetores Aracnídeos/parasitologia , Babesia/classificação , Babesiose/transmissão , Ixodidae/parasitologia , Infestações por Carrapato/parasitologia , Animais , Babesia/genética , Babesia/isolamento & purificação , Babesiose/parasitologia , República Tcheca/epidemiologia , Dermacentor/parasitologia , Feminino , Especificidade de Hospedeiro , Humanos , Ixodes/parasitologia , Masculino , RNA Ribossômico 18S/genética , Eslováquia/epidemiologia , Zoonoses
6.
J Eukaryot Microbiol ; 62(5): 670-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25939459

RESUMO

A complex wide-range study on the haemoproteid parasites of chelonians was carried out for the first time. Altogether, 811 samples from four tortoise species from an extensive area between western Morocco and eastern Afghanistan and between Romania and southern Syria were studied by a combination of microscopic and molecular-genetic methods. Altogether 160 Haemoproteus-positive samples were gathered in the area between central Anatolia and eastern Afghanistan. According to variability in the cytochrome b gene, two monophyletic evolutionary lineages were distinguished; by means of microscopic analysis it was revealed that they corresponded to two previously described species-Haemoproteus anatolicum and Haemoproteus caucasica. Their distribution areas overlap only in a narrow strip along the Zagros Mts. range in Iran. This fact suggests the involvement of two different vector species with separated distribution. Nevertheless, no vectors were confirmed. According to phylogenetic analyses, H. caucasica represented a sister group to H. anatolicum, and both of them were most closely related to H. pacayae and H. peltocephali, described from South American river turtles. Four unique haplotypes were revealed in the population of H. caucasica, compared with seven haplotypes in H. anatolicum. Furthermore, H. caucasica was detected in two tortoise species, Testudo graeca and Testudo horsfieldii, providing evidence that Haemoproteus is not strictly host-specific to the tortoise host species.


Assuntos
Haemosporida/classificação , Haemosporida/genética , Especificidade de Hospedeiro , Infecções Protozoárias em Animais/parasitologia , Tartarugas/parasitologia , Animais , Citocromos b/genética , DNA de Protozoário , Haemosporida/citologia , Haplótipos , Dados de Sequência Molecular , Filogenia
7.
Parasitology ; 142(6): 816-26, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25736219

RESUMO

The uniform morphology of the developmental stages of Haemogregarina species and the insufficient information supplied by the simplistic descriptions of previous authors complicates their differential diagnosis and proper species identification. In this study, we detected Haemogregarina spp. in 6 out of 22 (27.2%) examined turtles originating from Southeast Asia, Malayemys subtrijuga (n = 4), Sacalia quadriocellata (n = 1) and Platysternon megacephalum (n = 1), and compared them with the available literature data. Microscopic analysis of our isolates distinguished 2 morphological species, Haemogregarina pellegrini and one new species, being described in this paper as Haemogregarina sacaliae sp. n. Phylogenetic analyses based on 1210 bp long fragment of 18S rDNA sequences placed both haemogregarines firmly within the monophyletic Haemogregarina clade. Isolates of H. pellegrini from 2 distantly related turtle hosts, M. subtrijuga and P. megacephalum, were genetically identical. Despite the fact that numerous Haemogregarina species of turtles have been described, the incompleteness of the morphological data and relatively low host specificity provides the space for large synonymy within this taxon. Therefore, a complex approach combining microscopic analyses together with molecular-genetic methods should represent the basic standard for all taxonomic studies.


Assuntos
Apicomplexa/classificação , Apicomplexa/citologia , Infecções Protozoárias em Animais/parasitologia , Animais , Sudeste Asiático , Filogenia , Infecções Protozoárias em Animais/epidemiologia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie , Tartarugas
8.
Parasitology ; 141(4): 522-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24476992

RESUMO

The majority of Haemogregarina species have been based on the morphology of their erythrocytic stages and supposed strict host specificity. The quantity of species with a limited number of overlapping diagnostic traits has led to a considerable mess in haemogregarine taxonomy and significant synonymy. We analysed host specificity, intra- and interspecific variability, evolutionary relationships, and the distribution of the type species of the genus Haemogregarina--H. stepanowi. The morphology of blood stages and 18S rDNA sequences of this haemogregarine from four western Palaearctic hard-shelled freshwater turtles (Emys orbicularis, Mauremys caspica, Mauremys leprosa and Mauremys rivulata) were compared with Haemogregarina balli. Additional sequences of 18S rDNA of Haemogregarina-like isolates collected from three species of African hinged terrapins (genus Pelusios) were used to enlarge the dataset for phylogenetic analyses. Thirteen sequences (1085 bp) of Haemogregarina representing all four western Palaearctic turtle species were identical, corresponding to H. stepanowi, which is closely related to the Nearctic species H. balli. In our analyses, Haemogregarina spp. constituted a monophyletic clade sister to the genus Hepatozoon. Haemogregarina stepanowi possesses a wide distribution range from the Maghreb, through Europe, Turkey and the Middle East to Iran. We consider that the genus Haemogregarina has a low host specificity crossing the family level of its vertebrate hosts and that its distribution is likely to be linked to the vector and definitive host--the leech.


Assuntos
Coccidiose/veterinária , Eucoccidiida/isolamento & purificação , Interações Hospedeiro-Parasita , Sanguessugas/parasitologia , Tartarugas/parasitologia , Animais , Sequência de Bases , Coccidiose/parasitologia , DNA Ribossômico/química , DNA Ribossômico/genética , Vetores de Doenças , Eucoccidiida/classificação , Eucoccidiida/citologia , Eucoccidiida/genética , Feminino , Água Doce , Especificidade de Hospedeiro , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA/veterinária
9.
Zootaxa ; 3795: 523-48, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24870496

RESUMO

Using nearly range-wide sampling, we analyze up to 1848 bp of mitochondrial DNA of 183             helmeted terrapins and identify a minimum of 12 deeply divergent species-level clades. Uncorrected p distances of these clades equal or clearly exceed those between the currently recognized species of Pelusios, the genus most closely related to Pelomedusa. We correlate genetic discontinuities of Pelomedusa with data on morphology and endoparasites and describe six new Pelomedusa species. Moreover, we restrict the name Pelomedusa subrufa (Bonnaterre, 1789) to one genetic lineage and resurrect three further species from its synonymy, namely P. galeata (Schoepff, 1792), P. gehafie (Rüppell, 1835), and P. olivacea (Schweigger, 1812). In addition to these ten Pelomedusa species, we identify two further clades from Cameroon and Sudan with similar levels of genetic divergence that remain unnamed candidate species. We also note that some problematical terrapins from South Africa and Somalia may represent two additional candidate species. Some of the Pelomedusa species are morphologically distinctive, whilst others can only be identified by molecular markers and are therefore morphologically cryptic taxa.


Assuntos
Biodiversidade , DNA Mitocondrial , Tartarugas/classificação , África Subsaariana , Animais , Feminino , Madagáscar , Masculino , Oriente Médio , Filogenia , Tartarugas/anatomia & histologia , Tartarugas/genética
10.
Parasite ; 31: 1, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38353582

RESUMO

Blood parasites of the genus Hemolivia Petit, Landau, Baccam and Lainson, 1990 (Adeleorina: Karyolysidae) are hemogregarines of ectothermic vertebrates, such as lizards, chelonians, and toads. Only five species of Hemolivia from vertebrate hosts and one from their tick vector have been described so far. In the present study, Central American wood turtles (Rhinoclemmys pulcherrima manni) originating from Southern Nicaragua were screened for the presence of hemogregarines. Ten out of 30 specimens (33.3%) were positive for Hemolivia using both approaches - microscopy and PCR-based analyses. Phylogenetic analyses based on the 18S rRNA gene revealed the presence of two haplotypes, both placed as sister taxa in the Hemolivia clade. Their phylogenetic position was supported by high bootstrap values and high posterior probabilities, suggesting that there are at least two new distinct haplotypes corresponding to two distinct species. However, the specimens of each haplotype were microscopically indistinguishable from each other based on the gamont morphology, therefore, only a single species could be described and named, as Hemolivia pulcherrima n. sp. We consider that the uniform morphology of the most common blood stages of species of the genus Hemolivia complicates their differential diagnosis. Sequence divergence and different host spectra, therefore, remain the only differentiating tools.


Title: Espèces d'Hemolivia infectant les tortues peintes d'Amérique centrale (Rhinoclemmys pulcherrima manni) et problèmes de diagnostic différentiel au sein du genre Hemolivia. Abstract: Les parasites sanguins du genre Hemolivia Petit, Landau, Baccam et Lainson, 1990 (Adeleorina : Karyolysidae) sont des hémogrégarines de vertébrés ectothermes, tels que les lézards, les tortues et les crapauds. Seules cinq espèces d'Hemolivia provenant d'hôtes vertébrés et une de leur tique vectrice ont été décrites jusqu'à présent. Dans cette étude, des tortues peintes d'Amérique centrale (Rhinoclemmys pulcherrima manni) originaires du sud du Nicaragua ont été examinées pour détecter la présence d'hémogrégarines. Dix tortues sur 30 (33,3 %) étaient positives pour Hemolivia en utilisant les deux approches de microscopie et d'analyse de PCR. Les analyses phylogénétiques basées sur le gène de l'ARNr 18S ont révélé la présence de deux haplotypes, tous deux placés comme taxons frères dans le clade Hemolivia. Leur position phylogénétique était étayée par des valeurs de bootstrap et des probabilités postérieures élevées, suggérant qu'il existe au moins deux nouveaux haplotypes distincts correspondant à deux espèces distinctes. Cependant, les spécimens de chaque haplotype étaient impossibles à distinguer les uns des autres au microscope sur la base de la morphologie des gamontes. Par conséquent, une seule espèce a pu être décrite et nommée, comme Hemolivia pulcherrima n. sp. Nous considérons que l'uniformité de la morphologie des stades sanguins les plus courants des espèces du genre Hemolivia complique leur diagnostic différentiel. Les divergences de séquences et les différents spectres d'hôtes restent donc les seuls outils de différenciation.


Assuntos
Lagartos , Tartarugas , Animais , Filogenia , Diagnóstico Diferencial , Lagartos/parasitologia , América Central
11.
Int J Parasitol ; 53(2): 91-101, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36549441

RESUMO

The ornate dog tick (Dermacentor reticulatus) shows a recently expanding geographic distribution. Knowledge on its intraspecific variability, population structure, rate of genetic diversity and divergence, including its evolution and geographic distribution, is crucial to understand its dispersal capacity. All such information would help to evaluate the potential risk of future spread of associated pathogens of medical and veterinary concern. A set of 865 D. reticulatus ticks was collected from 65 localities across 21 countries, from Portugal in the west to Kazakhstan and southern Russia in the east. Cluster analyses of 16 microsatellite loci were combined with nuclear (ITS2, 18S) and mitochondrial (12S, 16S, COI) sequence data to uncover the ticks' population structures and geographical patterns. Approximate Bayesian computation was applied to model evolutionary relationships among the found clusters. Low variability and a weak phylogenetic signal showing an east-west cline were detected both for mitochondrial and nuclear sequence markers. Microsatellite analyses revealed three genetic clusters, where the eastern and western cluster gradient was supplemented by a third, northern cluster. Alternative scenarios could explain such a tripartite population structure by independent formation of clusters in separate refugia, limited gene flow connected with isolation by distance causing a "bipolar pattern", and the northern cluster deriving from admixture between the eastern and western populations. The best supported demographic scenario of this tick species indicates that the northern cluster derived from admixture between the eastern and western populations 441 (median) to 224 (mode) generations ago, suggesting a possible link with the end of the Little Ice Age in Europe.


Assuntos
Dermacentor , Rhipicephalus sanguineus , Cães , Animais , Dermacentor/genética , Filogenia , Teorema de Bayes , Refúgio de Vida Selvagem
12.
Parasitol Res ; 111(1): 301-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22434363

RESUMO

Dogs are competent reservoir hosts of several hemopathogens including zoonotic agents and can serve as readily available source of nutrition for many blood-feeding arthropods. Three hemopathogens had been detected for the first time in Jordan. The PCR prevalence of Anaplasma phagocytophilum, Hepatozoon canis, and piroplasmid DNA were 39.5%, 28.9%, and 7.9% (n=38) respectively. Sequencing of amplicons of PCR with universal primers targeting the 18S rRNA gene of piroplasmids shows the highest similarity to equine piroplasmids species Theileria equi from two dogs and Babesia caballi from a single dog. Ticks of two genera Rhipicephalus and Haemaphysalis, were detected in this study (n=268). The brown dog tick, Rhipicephalus sanguineus was the most abundant species (95.1%, n=255), followed by Haemaphysalis erinacei (3%, n=8) and Haemaphysalis parva (1.9%, n=5). The two Haemaphysalis species were detected for the first time from dogs in Jordan. Regarding its high prevalence, we expect R. sanguineus being a possible vector of detected pathogens.


Assuntos
Reservatórios de Doenças , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Ectoparasitoses/veterinária , Ixodidae/crescimento & desenvolvimento , Doenças Transmitidas por Carrapatos/veterinária , Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/isolamento & purificação , Animais , Babesia/genética , Babesia/isolamento & purificação , Sangue/microbiologia , Sangue/parasitologia , Coccídios/genética , Coccídios/isolamento & purificação , Cães , Ectoparasitoses/parasitologia , Feminino , Ixodidae/classificação , Jordânia , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Theileria/genética , Theileria/isolamento & purificação , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia
13.
Animals (Basel) ; 12(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35625176

RESUMO

Using data for the body size and shell shape of Algerian Testudo graeca, we assessed how proximate causes shaped the observed variation in the morphology of adults. All of the studied populations displayed significant sexual size and shape dimorphisms. Relative to body length, females displayed larger, more voluminous and domed shells than males. We found clear evidence that variation in body size at maturity influenced sexual size dimorphism. Body size at maturity depends on the duration of growth from hatching up to the point of reaching sexual maturity. In the studied populations, sexual maturity, estimated by counting growth lines, was always reached earlier in males than in females (a time difference of 1.4-3.0 years). Similar to sexual size dimorphism, geographic variation in adult body sizes was also influenced by variations in the corresponding sizes at maturity. Remarkably, the population with the largest tortoises had the latest mean maturation time: 9.1 for males and 10.5 for females. Thus, the later completion of maturation was a determinant for a larger size in adulthood. The largest tortoises among the studied populations were measured at the Djelfa locality, where the recorded sizes of males and females reached 186 and 230 mm, respectively.

14.
Protist ; 173(4): 125884, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35843169

RESUMO

The 18S rRNA gene is a widely used molecular marker for haemogregarines. In recent decades, many primers more or less specific to various haemogregarine genera have been designed. This study applied five commonly used primers targeting the 18S rRNA gene of haemogregarines to blood samples from 168 individuals of nine turtle species captured in Northern Vietnam. Three haemogregarine genera, Haemogregarina, Hemolivia, and Hepatozoon, were detected. Selective specificity of primers EF/ER, HemoFN/HemoRN, and Hemo1/Hemo2 to haemogregarine genera was observed and elucidated by primer-template mismatches. In total, 13 out of 168 turtles (prevalence 7.7%) were both microscopically and PCR positive for haemogregarines. Additionally, a single Heosemys grandis turtle was PCR positive but microscopically negative. Numerous turtles carried mixed infections by various haemogregarines; a single turtle was even coinfected by haemogregarines of all three studied genera: Haemogregarina, Hemolivia, and Hepatozoon. Among the detected haemogregarines, some provided sufficient molecular and morphological data for completing their species diagnosis. Two were described as new species: Haemogregarina cyclemydis sp. nov. from Cyclemys pulchristriata and Hemolivia cruciata sp. nov. from Cuora galbinifrons, so far the first Hemolivia from Southeast Asia. Haemogregarina cuorae Chai and Chen, 1990, required a redescription with reassignment to the genus Hepatozoon Miller, 1908.


Assuntos
Eucoccidiida , Tartarugas , Animais , Povo Asiático , Eucoccidiida/genética , Água Doce , Humanos , Filogenia , RNA Ribossômico 18S/genética , Tartarugas/genética , Vietnã
15.
Biology (Basel) ; 11(11)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36358263

RESUMO

We measured and compared the reproductive traits of the Mediterranean stripe-necked turtles Mauremys leprosa living in highly degraded-polluted vs. intact natural habitats in Algeria. Data on reproduction were obtained by using X-ray examination of gravid females and examination of nests. The results were opposite to the negative trend confirmed in most freshwater turtles exposed to pollution and suggested the ability of this species to flourish instead in highly degraded-polluted habitats. An optimum development was recorded for several reproductive patterns of the studied freshwater turtle under conditions considered uninhabitable for other vertebrates. Females exhibited record body sizes among conspecifics, which allowed them to carry significantly larger clutches, exceeding by up to 3 eggs the previously largest reported clutch. The mean clutch size (8.79 ± 2.70 eggs) was also higher than findings from previous studies, except for in some other polluted habitats. Furthermore, large females even with large clutches carried large eggs. Egg measurements in the disturbed habitat revealed new records exceeding those previously noted; in egg length (by 3.0 mm), egg width (by 2.8 mm), egg mass (by 1.8 g), and clutch mass (by 18.6 g). In comparison, the usual reproductive performances were observed in the intact natural habitat; female body sizes were significantly smaller and carried fewer eggs of smaller size.

17.
Exp Appl Acarol ; 54(3): 277-84, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21431927

RESUMO

The tortoise tick Hyalomma aegyptium has a typical three-host life-cycle. Whereas its larvae and nymphs are less host-specific feeding on a variety of tetrapods, tortoises of the genus Testudo are principal hosts of adults. Ticks retained this trait also in our study under laboratory conditions, while adults were reluctant to feed on mammalian hosts. Combination of feeding larvae and nymphs on guinea pigs and feeding of adults on Testudo marginata tortoises provided the best results. Feeding period of females was on average 25 days (range 17-44), whereas males remain after female engorgement on tortoise host. Female pre-oviposition period was 14 days (3-31), followed by 24 days of oviposition (18-29). Pre-eclosion and eclosion, both together, takes 31 days (21-43). Larvae fed 5 days (3-9), then molted to nymphs after 17 days (12-23). Feeding period of nymphs lasted 7 days (5-10), engorged nymphs molted to adults after 24 days (19-26). Sex ratio of laboratory hatched H. aegyptium was nearly equal (1:1.09). The average weight of engorged female was 0.95 (0.72-1.12) g. The average number of laid eggs was 6,900 (6,524-7,532) per female, it was significantly correlated with weight of engorged female. Only 2.8% of engorged larvae and 1.8% of engorged nymphs remained un-molted and died. Despite the use of natural host species, feeding success of females reached only 45%. The whole life-cycle was completed within 147 days (98-215).


Assuntos
Ixodidae/fisiologia , Tartarugas/parasitologia , Animais , Comportamento Alimentar , Feminino , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Longevidade , Masculino , Muda , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Oviposição , Razão de Masculinidade
18.
Eur J Protistol ; 79: 125780, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34020115

RESUMO

The analyses of molecular data represent an effective tool for increasing the credibility of taxonomy and facilitate the description of species. Nevertheless, in haemoprotozoa, the growing amount of available sequential data is not matched by the still limited number of well-defined species. We identified four protistan haemoparasites in North Iranian reptiles: two Hepatozoon and two Schellackia species. Hepatozoon colubri and Hepatozoon ophisauri were morphologically identified in their type hosts, their partial 18S rDNA was analyzed, and thorough literature data were included in their redescription. The scarce data on the detected Schellackia spp. did not allow for their formal species description. Using an integrative approach, including morphological and geographical features, host specificity, molecular data, and the data published thus far, we face the following main difficulties hindering reliable diagnosis. (1) The lack of molecular data on well-described and named species. (2) The insufficiency of using only morphological and biological features, or only sequential data without morphology, to perform an absolutely reliable species diagnosis. (3) Typical morphological features are more substantial than metric means. (4) High risk of synonymy is present in taxonomy of blood Protista. (5) Artefacts caused by blood smear processing further complicate the correct morphological determination.


Assuntos
Eucoccidiida/classificação , Répteis/parasitologia , Animais , Coccidiose/parasitologia , DNA de Protozoário/genética , Eucoccidiida/genética , Irã (Geográfico) , RNA Ribossômico 18S/genética , Especificidade da Espécie
19.
Ticks Tick Borne Dis ; 12(1): 101559, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33137638

RESUMO

Micro-computed tomography (micro-CT) is an exceptional imaging modality which is limited in visualizing soft biological tissues that need pre-examination contrasting steps, which can cause serious deformation to sizeable specimens like engorged ticks. The aim of this study was to develop a new technique to bypass these limitations and allow the imaging of fed ticks in their natural state. To accomplish this, adult Ixodes ricinus females were allowed to engorge in vitro on blood supplemented with PEGylated gold nanoparticles (PEG-AuNPs). In total, 73/120 females divided into 6 groups engorged on blood enriched with 0.07-2.16 mg PEG-AuNPs per ml of blood. No toxic effect was observed for any of the tested groups compared to the control group, in which 12/20 females engorged on clear blood. The ticks were scanned on a Bruker micro-CT SkyScan 1276. The mean radiodensity of the examined ticks exceeded 0 Hounsfield Units only in the case of the two groups with the highest concentration. The best contrast was observed in ticks engorged on blood with the highest tested concentration of 2.16 mg/mL PEG-AuNPs. In these ticks, the midgut and rectal sac were clearly visible. Also, the midgut lumen volume was computed from segmented image data. The reduction in midgut volume was documented during the egg development process. According to this pilot study, micro-CT of ticks engorged on blood supplemented with contrasting agents in vitro may reveal additional information regarding the engorged ticks' anatomy.


Assuntos
Ouro , Ixodes , Nanopartículas Metálicas , Microtomografia por Raio-X/métodos , Animais , Sangue , Comportamento Alimentar , Feminino
20.
Transbound Emerg Dis ; 68(3): 1685-1696, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32966705

RESUMO

Studies of tick-borne diseases (TBDs) in Europe focus on pathogens with principal medical importance (e.g. Lyme disease and tick-borne encephalitis), but we have limited epidemiological information on the neglected pathogens, such as the members of the genera Anaplasma, Rickettsia, Babesia and Candidatus Neoehrlichia mikurensis. Here, we integrated an extensive field sampling, laboratory analysis and GIS models to provide first publicly available information on pathogen diversity, prevalence and infection risk for four overlooked zoonotic TBDs in the Czech Republic. In addition, we assessed the effect of landscape variables on the abundance of questing ticks at different spatial scales and examined whether pathogen prevalence increased with tick density. Our data from 13,340 ticks collected in 142 municipalities showed that A. phagocytophilum (MIR = 3.5%) and Ca. Neoehrlichia mikurensis (MIR = 4.0%) pose geographically uneven risks with localized hotspots, while Rickettsia (MIR = 4.9%) and Babesia (MIR = 1.1%) had relatively homogeneous spatial distribution. Landscape variables had significant effect on tick abundance up to the scale of 1 km around the sampling sites. Questing ticks responded positively to landscape diversity and configuration, especially to forest patch density that strongly correlates with the amount of woodland-grassland ecotones. For all four pathogens, we found higher prevalence in places with higher densities of ticks, confirming the hypothesis that tick abundance amplifies the risk of TB infection. Our findings highlight the importance of landscape parameters for tick vectors, likely due to their effect on small vertebrates as reservoir hosts. Future studies should explicitly investigate the combined effect of landscape parameters and the composition and population dynamics of hosts on the host-vector-pathogen system.


Assuntos
Anaplasmataceae/isolamento & purificação , Babesia/isolamento & purificação , Ixodidae/microbiologia , Ixodidae/parasitologia , Rickettsia/isolamento & purificação , Zoonoses , Animais , República Tcheca , Meio Ambiente , Zoonoses/microbiologia , Zoonoses/parasitologia
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