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1.
Animals (Basel) ; 13(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36830510

RESUMO

Island biogeography theories predict that characteristics such as island size, age, and isolation interplay in host-parasite dynamics. In this study, we analyzed haemogregarines of the Aegean wall lizard, Podarcis erhardii, to investigate how island characteristics relate to parasite prevalence and intensity. A previous assessment of 19 Greek island populations suggested that isolation time and host population density were key predictors of haemogregarines. Here, by combining microscopy and genetic techniques, we extend this previous study to four additional islands: Syros, Folegandros, Santorini and Nea Kameni. We also recorded the prevalence of ticks and mites, definitive hosts for these parasites. The genetically identified haemogregarines are part of a clade with parasites from other lizard species, including some considered as Karyolysus, but others assigned to Hepatozoon. The prevalence of these parasites differed significantly between islands, while their intensity did not. The presence of ticks was associated with endoparasite prevalence, and males were more frequently infected by haemogregarines than females. Combining our data with that of the previous study, we found no significant impact of the island age and area on parasite prevalence. We also confirmed the presence of the unrelated parasite genus Schellackia through microscopy and DNA sequencing, which is the first record of this genus in this host species. Our results further highlight the complexity of host-parasite systems.

2.
Horiz. enferm ; 34(2): 190-202, 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1509287

RESUMO

INTRODUCCIÓN. La satisfacción laboral se considera un indicador clave de la atención de calidad por lo tanto el personal de enfermería debe estar inmerso en un ambiente laboral positivo que impacte en su desarrollo profesional y en la atención que proporciona. OBJETIVO. Determinar la satisfacción laboral del personal de enfermería en un hospital de segundo nivel. METODOLOGÍA. Estudio cuantitativo, descriptivo y transversal en una muestra de 92 enfermeras(os) de los servicios de hospitalización de un hospital de segundo nivel. Se aplicó una cédula de datos sociodemográficos y laborales y el cuestionario Font-Roja, versión ampliada, se utilizó el programa SPSS versión 24 para el análisis de los datos mediante estadística descriptiva. RESULTADOS. La media de edad de los participantes fue de 38,9 años(DE= 10,2), respecto al sexo predominó el femenino (77,2%). El 84,8% del personal de enfermería se encuentra satisfecho laboralmente, seguido por el 14,1% como insatisfecho y solo el 1,1% como medianamente satisfecho. Los factores con mayor satisfacción laboral fueron presión en el trabajo (M= 3,6, DE= 0,61), seguido por relación interpersonal con sus superiores (M= 3,6, DE= 0,82) y satisfacción por el trabajo (M= 3,5, DE= 0,71).CONCLUSIONES. El personal de enfermería se encuentra satisfecho con su trabajo, pero es importante explorar a profundidad los factores que pueden influir y repercutir en su actividad profesional.


INTRODUCTION. Because work satisfaction is considered a key indicator of quality care, nurses should be immersed in an environment that positively impacts their professional development and the care they provide. OBJECTIVE. To determine the work satisfaction of nursing staff in a second level hospital. METHODOLOGY. Quantitative, descriptive and cross-sectional study based on a sample of 92 nurses from the inpatient services of a second level hospital. A sociodemographic and labor data questionnaire, and an extended version of the Font-Roja questionnaire, were applied, and SPSS version 24 was used for data analysis by means of descriptive statistics. RESULTS. The mean age of the participants was 38.9 years (SD= 10.2), with female the dominant gender (77.2%). A total of 84.8% of the nursing personnel were satisfied with their work, followed by 14.1% as dissatisfied and only 1.1% as moderately satisfied. The factors related to the highest overall work satisfaction were job pressure (M= 3.6, SD= 0.61), followed by interpersonal relationship with superiors (M= 3.6, SD= 0.82) and job satisfaction (M= 3.5, SD= 0.71). CONCLUSIONS. The nursing staff were generally satisfied with their work, but it is important to explore in depth the factors that may have an impact on their professional activity.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Cuidados de Enfermagem
3.
Zootaxa ; 5150(4): 556-578, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-36095647

RESUMO

Urocotyledon inexpectata, a small gecko endemic to the granitic islands of the Seychelles, has previously been demonstrated to comprise two highly distinct clades based on mitochondrial and nuclear DNA sequences, with one lineage exclusive to a northern group of islands, and the second lineage exclusive to the more southerly islands. Here we complement the genetic data with additional analyses to determine if the clades should be considered distinct species. We present and analyse new morphological data, including skull and jaw osteology, and supplement the available genetic data with DNA sequences for individuals from the previously unsampled island of Felicit, which cluster with the other northern island samples. Despite the high morphological similarity between Urocotyledon populations from northern and southern islands, diagnostic characters were identified, with the northern lineage having a more completely ossified skull, more tooth loci on maxilla and dentary, shorter hindlimbs, relatively smaller eye diameter and relatively wider head. We therefore describe the northern lineage as a distinct species, Urocotyledon norzilensis sp. nov., and discuss the biological and conservation management implications of this taxonomic action.


Assuntos
Lagartos , Animais , Lagartos/genética , Filogenia , Seicheles
4.
PLoS One ; 17(7): e0270032, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35793291

RESUMO

Studying collection specimens is often the only way to unravel information about recent extinctions. These can reveal knowledge on threats and life traits related to extinction, and contribute, by extrapolation, to the conservation of extant species. However, high-throughput sequencing methods have rarely been applied to extinct species to reveal information on their ecology. Insular species are especially prone to extinction. We studied the gut contents of three specimens of the extinct giant skink Chioninia coctei of the Cabo Verde Islands using microscopy and DNA-metabarcoding. The presence of Tachygonetria adult nematodes suggests plants as important diet items. Our metabarcoding approach also identified plants and, additionally, invertebrates, supporting the hypothesis of C. coctei's generalist diet. The absence of vertebrates in the digestive contents may reflect the decline of seabirds on the Desertas Islands that could have contributed to the debilitation of the giant skink, already depleted by persecution and severe droughts. Even with a small sample size, this study contributes to shedding light on the trophic roles of this enigmatic extinct species and emphasizes the need to develop holistic conservation plans for island threatened taxa. Additionally, it illustrates the potential of integrating up-to-date molecular methods with traditional approaches to studying collection specimens to help to solve ecological puzzles in other ecosystems.


Assuntos
Dieta , Extinção Biológica , Manejo de Espécimes , Animais , Cabo Verde , Dieta/história , Dieta/veterinária , Ecossistema , História do Século XX
5.
Syst Parasitol ; 99(3): 367-373, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35312903

RESUMO

Molecular tools have revolutionized assessments of blood parasites in freshwater turtles. In the Iberian Peninsula and North Africa, two native species of terrapins occur, Emys orbicularis (Linnaeus) and Mauremys leprosa (Schweigger). Both have been identified as hosts for the blood parasite Haemogregarina stepanowi Danilewsky, 1885, which has also been found in related species. However, recent assessments of M. leprosa have identified several distinct genetic lineages of these parasites in this host, while only three haemogregarine lineages were identified in E. orbicularis in Tunisia. Here, we screened 215 individuals of E. orbicularis from the Iberian Peninsula, Menorca Island and Morocco for haemogregarine parasites using partial 18S rRNA gene sequences to estimate relationships. Three unrelated lineages of parasites were detected, one presumed H. stepanowi and two lineages previously known from M. leprosa. A considerable undescribed diversity of parasites exists within these vertebrate host species, while mixed infection and host-sharing is also widespread. Considering that E. orbicularis is near threatened in this region, it is of great importance to identify the parasites infecting it, and to further assess the potential deleterious impact of these diverse parasites on their hosts.


Assuntos
Apicomplexa , Eucoccidiida , Parasitos , Tartarugas , Animais , Especificidade da Espécie , Tartarugas/parasitologia
6.
Parasitology ; 149(2): 193-202, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35234602

RESUMO

In parasite­host interactions host species may differ in their ability to fight parasitic infections, while other ecological interactions, including competition, may differentially alter their physiological state, making them even more susceptible to parasites. In this study, we analyse the haemogregarine blood parasites infecting two competing lizard species, Iberolacerta horvathi and Podarcis muralis, and explore host­parasite relationships under different host competition scenarios. Both species were infected with haemogregarine parasites belonging to the genus Karyolysus. Using the 18S rRNA gene, six new Karyolysus haplotypes were identified clustering with other Central and Eastern European samples, and widely shared between both lizard hosts. Haemogregarine infections were detected at all sampled sites with over 50% of individuals parasitized. Overall, I. horvathi was more frequently and also more intensely parasitized than P. muralis, with higher infection rates observed in syntopy. Males of both species tended to be more frequently infected and showed a higher infection intensity than conspecific females. The results suggest that parasitisation by haemogregarines may be relevant in the dynamics of the competitive relationship between these lizard species. More studies, including immunological response analysis, and the identification of the vectors are needed to better understand host­parasite relationships and competition.


Assuntos
Eucoccidiida , Lagartos , Animais , Eucoccidiida/genética , Feminino , Haplótipos , Interações Hospedeiro-Parasita , Humanos , Lagartos/parasitologia , Masculino , Filogenia , RNA Ribossômico 18S/genética
7.
Ticks Tick Borne Dis ; 13(3): 101924, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35217334

RESUMO

Tortoise ticks, Hyalomma aegyptium, are considered so strongly associated with their hosts that they are even used as indirect indicators for them. In such a case, a robust pattern of congruence between host and parasite could be expected, with phylogeographic breaks within the host being reflected in their parasites. We sequenced two mitochondrial partial gene regions (12S rRNA and Cytochrome Oxidase 1) from ticks across northern Africa and Anatolia, and compared patterns of variation with those identified in its main host, Testudo graeca. Two distinct haplogroups were identified, both of which were found distributed across much of northern Africa. This pattern does not reflect the known variation within the host, which has multiple, geographically disjunct subspecies in this region, but rather the major climatic zones. This relationship can be explained by adaptive processes to environmental conditions influenced by the climate, as well as by the spatial structure of the communities of tick potential hosts in larval and nymphal stages. Extensive anthropogenic movement of tortoises may also obscure congruence patterns between H. aegyptium ticks and their hosts.


Assuntos
Ixodidae , Infestações por Carrapato , Carrapatos , Tartarugas , Animais , Ixodidae/parasitologia , Ninfa , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária , Tartarugas/parasitologia
8.
Transbound Emerg Dis ; 69(4): 1951-1962, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34125999

RESUMO

Ticks carry a diverse community of microorganisms including non-pathogenic symbionts, commensals, and pathogens, such as viruses, bacteria, protozoans, and fungi. The assessment of tick-borne microorganisms (TBM) in tortoises and their ticks is essential to understand their eco-epidemiology, and to map and monitor potential pathogens to humans and other animals. The aim of this study was to characterize the diversity of microorganisms found in ticks collected from the spur-thighed tortoise (Testudo graeca) in North Africa and Anatolia. Ticks feeding on wild T. graeca were collected, and pathogens were screened by polymerase chain reaction using group-specific primers. In total, 131 adult Hyalomma aegyptium ticks were collected from 92 T. graeca in Morocco (n = 48), Tunisia (n = 2), Algeria (n = 70), and Turkey (n = 11). Bacteria and protozoa detected included Hemolivia mauritanica (22.9%), Midichloria mitochondrii (11.4%), relapsing-fever borreliae (8.4%), Ehrlichia spp. (7.6%), Rickettsia spp. (3.4%), Borrelia burgdorferi s.l. (0.9%), Francisella spp. (0.9%), and Wolbachia spp. (0.8%). The characterization of Rickettsia included R. sibirica mongolitimonae (Algeria), R. aeschlimannii (Turkey), and R.africae (Morocco). Hemolivia mauritanica and Ehrlichia spp. prevalence varied significantly with the sampling region/country. We did not detect significant associations in microorganism presence within ticks, nor between microorganism presence and tick mitochondrial DNA haplogroups. This is the first report of Francisella persica-like, relapsing fever borreliae, M. mitochondrii, and Wolbachia spp. in H. aegyptium ticks collected from wild hosts from the South and Eastern Mediterranean region, and of R. sibirica mongolitimonae and R. africae in H. aegyptium from Algeria and Morocco, respectively. Given that T. graeca is a common species in commercial and non-commercial pet trade, the evaluation of the role of this species and its ticks as hosts for TBM is particularly relevant for public health.


Assuntos
Borrelia , Ixodidae , Rickettsia , Carrapatos , Tartarugas , Animais , Ehrlichia , Humanos , Ixodidae/microbiologia , Rickettsia/genética , Carrapatos/microbiologia , Tunísia/epidemiologia , Turquia/epidemiologia , Tartarugas/parasitologia
9.
Folia Parasitol (Praha) ; 682021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34642290

RESUMO

Although intranuclear coccidiosis was first identified in chelonians less than 30 years ago, it is now considered an important emerging disease. Symptoms include anorexia, weakness and weight loss, potentially leading to death of the infected animal. The use of molecular tools has led to improved diagnosis and has also led to an increase in known host species. Here we report a putative intranuclear coccidium in Mauremys leprosa (Schweigger), from Morocco, based on 18S rDNA sequence analysis. This is, to the best of our knowledge, the first report of this parasite from a freshwater terrapin species.


Assuntos
Coccídios/isolamento & purificação , Coccidiose/veterinária , Tartarugas/parasitologia , Animais , Coccídios/genética , Coccidiose/parasitologia , DNA Ribossômico/genética , Água Doce/parasitologia , Marrocos
10.
Parasitol Res ; 120(8): 2953-2957, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34232389

RESUMO

Invasive species can carry parasites to introduced locations, which may be key to understand the success or failure of species establishment and the invasive potential of introduced species. We compared the prevalence and infection levels of haemogregarine blood parasites between two sympatric congeneric species in Lisbon, Portugal: the invasive Italian wall lizard (Podarcis siculus) and the native green Iberian wall lizard (Podarcis virescens). The two species had significant differences in their infection levels: while P. virescens had high prevalence of infection (69.0%), only one individual of P. siculus was infected (3.7%), and while P. virescens exhibited an average intensity of 1.36%, the infected P. siculus individual had an infection rate of only 0.04%. Genetic analyses of 18S rRNA identified two different haemogregarine haplotypes in P. virescens. Due to the low levels of infection, we were not able to amplify parasite DNA from the infected P. siculus individual, although it was morphologically similar to those found in P. virescens. Since other studies also reported low levels of parasites in P. siculus, we hypothesize that this general lack of parasites could be one of the factors contributing to its competitive advantage over native lizard species and introduction success.


Assuntos
Lagartos , Parasitos , Animais , Teorema de Bayes , Feminino , Haplótipos , Espécies Introduzidas , Lagartos/parasitologia , Masculino , Filogenia , Portugal
11.
Syst Parasitol ; 98(5-6): 547-557, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34322858

RESUMO

Distribution, prevalence and parasitaemia of apicomplexan parasites of the genus Haemogregarina were studied in 858 freshwater turtles (735 Mauremys leprosa leprosa and 123 Mauremys leprosa saharica) throughout 30 localities from Morocco. Blood smears were collected from the turtles and partial 18S rRNA sequence data used to infer genetic diversity and phylogenetic relationships. Of the 858 individuals analyzed by microscopy 22.7% were infected, from 16 M. leprosa leprosa localities. Individuals of M. leprosa saharica sampled south of the High Atlas Mountains were not infected, probably due to the absence or rarity of the leech vectors in these localities. Within M. leprosa leprosa, we did not identify any patterns between geography and prevalence, which varied between 10% (Oued Nfiss) to 100% (Oued Tassaout). Five distinct genetic lineages were identified, indicating the likely presence of multiple species of haemogregarines, one of which probably corresponds to Haemogregarina stepanowi. Mixed infections were also detected. Additional studies are needed to better understand the ecology and epidemiology of this parasite in turtles, as well as the host-parasite relationship with their definitive hosts, leeches.


Assuntos
Apicomplexa , Eucoccidiida , Tartarugas , Animais , Apicomplexa/genética , Eucoccidiida/genética , Marrocos , Filogenia , Especificidade da Espécie , Tartarugas/parasitologia
12.
Mol Phylogenet Evol ; 161: 107152, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33741534

RESUMO

Phylogenetic relationships of sub-Saharan African natricine snakes are understudied and poorly understood, which in turn has precluded analyses of the historical biogeography of the Seychelles endemic Lycognathophis seychellensis. We inferred the phylogenetic relationships of Seychelles and mainland sub-Saharan natricines by analysing a multilocus DNA sequence dataset for three mitochondrial (mt) and four nuclear (nu) genes. The mainland sub-Saharan natricines and L. seychellensis comprise a well-supported clade. Two maximally supported sets of relationships within this clade are (Limnophis,Natriciteres) and (Afronatrix,(Hydraethiops,Helophis)). The relationships of L. seychellensis with respect to these two lineages are not clearly resolved by analysing concatenated mt and nu data. Analysed separately, nu data best support a sister relationship of L. seychellensis with (Afronatrix,(Hydraethiops,Helophis)) and mt data best support a sister relationship with all mainland sub-Saharan natricines. Methods designed to cope with incomplete lineage sorting strongly favour the former hypothesis. Genetic variation among up to 33 L. seychellensis from five Seychelles islands is low. Fossil calibrated divergence time estimates support an overseas dispersal of the L. seychellensis lineage to the Seychelles from mainland Africa ca. 43-25 million years before present (Ma), rather than this taxon being a Gondwanan relic.


Assuntos
Colubridae/genética , Evolução Molecular , Filogenia , Filogeografia , África Subsaariana , Animais , Análise de Sequência de DNA , Seicheles
13.
Parasitology ; 148(1): 42-52, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33070783

RESUMO

Although parasites represent a major component of biodiversity, they remain poorly assessed, especially in remote regions. In this study, we screened 461 reptiles from Socotra, the largest and most biologically diverse archipelago in Arabia. Using 18S rRNA primers, we detected various apicomplexan parasites, namely haemogregarines, sarcocystids and eimeriids. Haemogregarines were the most common and genetically diverse, followed by sarcocystids (genus Sarcocystis) and eimeriids (genera Isospora and Lankesterella). All were related to parasites of other reptiles, including species from Arabia, Northern Africa and Asia. Like their 29 endemic reptile hosts, almost all Socotran parasites presented high genetic divergence and ecological differences from those found elsewhere, and probably represent undescribed endemic species. Among hosts, skinks were the most parasitized, which contrasted with similar studies from other areas, probably due to their more generalist diet and habitat use. As expected due to its high species richness, geckos harboured the highest parasite diversity in the archipelago. Parasite diversity also seemed to be correlated to island size, as the largest island harboured most haplotypes. This study emphasizes the importance of screening parasites in wild hosts from remote regions and of considering host ecology to understand disease transmission across taxa.


Assuntos
Coccidiose/transmissão , Eucoccidiida , Répteis/parasitologia , Animais , Animais Selvagens/parasitologia , Biodiversidade , Coccidiose/veterinária , DNA de Protozoário , Eimeriidae/genética , Eimeriidae/isolamento & purificação , Eucoccidiida/genética , Eucoccidiida/isolamento & purificação , Variação Genética , Especificidade de Hospedeiro , Ilhas do Oceano Índico/epidemiologia , Isospora/genética , Isospora/isolamento & purificação , Lagartos/parasitologia , Filogenia , Prevalência , RNA Ribossômico 18S/genética , Sarcocystis/genética , Sarcocystis/isolamento & purificação
14.
Parasitol Res ; 119(12): 4281-4286, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32870404

RESUMO

During spring 2018, we captured 101 spur-thighed tortoises, Testudo graeca, from seven localities in central Morocco. All tortoises were examined for the presence of blood parasites Hemolivia mauritanica and Hyalomma aegyptium ticks, the known vectors. We looked for H. mauritanica infection by examination of blood smears and by genetic analysis with PCR using extractions from both tortoises and ticks. On all tortoises collected, 71.29% were infested with at least one tick, with a mean infestation intensity of 7.12 ticks/tortoise and maximum of 15.55 ticks/tortoises in Had Draa locality (Essaouira region). Although the definitive host is present and abundant in all tortoise populations, all blood samples were Hemolivia-negative. Our results support and confirm the finding of studies previously conducted in other populations of Morocco and indicate that H. mauritanica has a narrower distribution range than its tick vector.


Assuntos
Coccidiose/veterinária , Eucoccidiida/fisiologia , Tartarugas/parasitologia , Animais , Animais Selvagens , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/transmissão , DNA de Protozoário/genética , Eucoccidiida/citologia , Eucoccidiida/genética , Ixodidae/parasitologia , Ixodidae/fisiologia , Marrocos/epidemiologia , Estações do Ano , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária
15.
Parasitology ; 146(6): 728-739, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30871644

RESUMO

Oceanic islands are hotspots of biodiversity due to their high levels of endemism, with the Canary Islands being a notable example. A previous molecular study on the biogeography and host associations of haemogregarines (Apicomplexa: Adeleorina) infecting lizards from this archipelago detected seven parasite haplogroups. These haplogroups exhibited high host-specificity and geographical structure, suggesting that they might correspond to distinct biological identities. In this study, along with sequencing a longer fragment of the 18S rRNA, we further explore the distinctiveness of these parasites by analysing their morphology, effects on host erythrocytes and parasitaemia levels. These lines of evidence together with their genetics, host associations, frequency of occurrence and geographical distribution support them as different biological entities. As such, we describe seven new species: Karyolysus canariensis sp. nov., Karyolysus galloti sp. nov., Karyolysus stehlini sp. nov., Karyolysus gomerensis sp. nov., Karyolysus atlanticus sp. nov., Karyolysus tinerfensis sp. nov. and Karyolysus makariogeckonis sp. nov. These new taxa are further examples of endemic diversity in the Canarian archipelago. They also contribute to clarify the taxonomy within the Apicomplexa, a phylum estimated to have one of the lowest percentages of described species.


Assuntos
Coccidiose/veterinária , Eucoccidiida/classificação , Eucoccidiida/isolamento & purificação , Lagartos/parasitologia , Animais , Análise por Conglomerados , Coccidiose/parasitologia , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Eucoccidiida/genética , Haplótipos , Especificidade de Hospedeiro , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Espanha
16.
Turkiye Parazitol Derg ; 42(1): 28-32, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29780016

RESUMO

OBJECTIVE: Understanding the processes that drive parasite diversification, distribution, and abundance is central to disentangle the dynamics and evolution of diseases. In this study, we screened African rock pythons from Nigeria for the presence of blood parasites to assess their distribution, diversity, and phylogenetic relationships. METHODS: A total of 21 captive African rock pythons collected from across 11 locations in Nigeria were sampled between August 2016 and January 2017. Samples were microscopically and genetically analyzed. RESULTS: From the blood smears analyzed, 10 (47.6%) snakes were found to be infected with haemogregarines. Eight of the infected samples were genetically assessed and confirmed as haemogregarines of the recently described Bartazoon group. Two haplotypes were retrieved, of which one was distributed in the northern-central sampled localities and the other in the southern localities. The two haplotypes were clustered in a clade of haemogregarines from snake, gecko, and rodent hosts, and among them, the haemogregarine species Hepatozoon ayorgbor was described from the ball python Python regius. CONCLUSIONS: Two haemogregarine haplotypes in Nigerian rock pythons, which appear to have a geographical pattern across the country, were detected in this study.


Assuntos
Boidae/genética , Animais , Animais Selvagens , Boidae/classificação , Variação Genética , Nigéria , Filogenia
17.
Parasit Vectors ; 11(1): 190, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29554983

RESUMO

BACKGROUND: Host-parasite relationships are expected to be strongly shaped by host specificity, a crucial factor in parasite adaptability and diversification. Because whole host communities have to be considered to assess host specificity, oceanic islands are ideal study systems given their simplified biotic assemblages. Previous studies on insular parasites suggest host range broadening during colonization. Here, we investigate the association between one parasite group (haemogregarines) and multiple sympatric hosts (of three lizard genera: Gallotia, Chalcides and Tarentola) in the Canary Islands. Given haemogregarine characteristics and insular conditions, we hypothesized low host specificity and/or occurrence of host-switching events. METHODS: A total of 825 samples were collected from the three host taxa inhabiting the seven main islands of the Canarian Archipelago, including locations where the different lizards occurred in sympatry. Blood slides were screened to assess prevalence and parasitaemia, while parasite genetic diversity and phylogenetic relationships were inferred from 18S rRNA gene sequences. RESULTS: Infection levels and diversity of haplotypes varied geographically and across host groups. Infections were found in all species of Gallotia across the seven islands, in Tarentola from Tenerife, La Gomera and La Palma, and in Chalcides from Tenerife, La Gomera and El Hierro. Gallotia lizards presented the highest parasite prevalence, parasitaemia and diversity (seven haplotypes), while the other two host groups (Chalcides and Tarentola) harbored one haplotype each, with low prevalence and parasitaemia levels, and very restricted geographical ranges. Host-sharing of the same haemogregarine haplotype was only detected twice, but these rare instances likely represent occasional cross-infections. CONCLUSIONS: Our results suggest that: (i) Canarian haemogregarine haplotypes are highly host-specific, which might have restricted parasite host expansion; (ii) haemogregarines most probably reached the Canary Islands in three colonization events with each host genus; and (iii) the high number of parasite haplotypes infecting Gallotia hosts and their restricted geographical distribution suggest co-diversification. These findings contrast with our expectations derived from results on other insular parasites, highlighting how host specificity depends on parasite characteristics and evolutionary history.


Assuntos
Apicomplexa/fisiologia , Especificidade de Hospedeiro , Lagartos/parasitologia , Infecções Protozoárias em Animais/parasitologia , África , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/isolamento & purificação , Evolução Molecular , Variação Genética , Ilhas , Lagartos/classificação , Filogenia
18.
Mol Phylogenet Evol ; 120: 118-128, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29196204

RESUMO

Biogeographic and evolutionary patterns in the North African portion of the Western Palaearctic are poorly known. A high fraction of undescribed diversity is expected in this region, especially in groups such as reptiles. Here we used mitochondrial (12S, 16S, cytb) and nuclear (pomc, rag2, cmos) markers and morphological data to investigate phyletic diversification and phylogeographical structure in the amphisbaenian Trogonophis wiegmanni endemic to the Maghreb. Phylogenetic and molecular dating analyses based on gene trees and species trees support three deeply divergent lineages of Pliocene origin, two in Morocco and one in central Algeria and Tunisia. Parapatry, reciprocal monophyly, high genetic divergence and limited morphological differentiation between them suggest that these lineages represent independent cryptic taxonomic units. Emerging lines of evidence from this study and from available literature on Maghreb taxa support (i) a major biogeographic break between western and eastern Maghreb and (ii) a role of the Atlas as a biogeographic divide within the western Maghreb (Morocco). The origin of these biogeographic units is probably associated with the evolutionary events prompted by the Late Miocene palaeogeographic setting and later by Plio-Pleistocene climatic changes and their interplay with prominent orographic barriers within North Africa.


Assuntos
Lagartos/classificação , África do Norte , Proteínas de Anfíbios/classificação , Proteínas de Anfíbios/genética , Proteínas de Anfíbios/metabolismo , Animais , Biodiversidade , Evolução Biológica , DNA Mitocondrial/química , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/classificação , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Lagartos/genética , Marrocos , Filogenia , Filogeografia , Pró-Opiomelanocortina/classificação , Pró-Opiomelanocortina/genética , Pró-Opiomelanocortina/metabolismo , RNA Ribossômico/química , RNA Ribossômico/classificação , RNA Ribossômico/genética
19.
Mol Ecol ; 27(2): 533-549, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29219226

RESUMO

Episodes of expansion and isolation in geographic range over space and time, during which parasites have the opportunity to expand their host range, are linked to the development of host-parasite mosaic assemblages and parasite diversification. In this study, we investigated whether island colonization events lead to host range oscillations in a taxon of host-specific parasitic nematodes of the genus Spauligodon in the Canary Islands. We further investigated whether range oscillations also resulted in shifts in host breadth (i.e., specialization), as expected for parasites on islands. Parasite phylogeny and divergence time estimates were inferred from molecular data with Bayesian methods. Host divergence times were set as calibration priors after a priori evaluation with a global-fit method of which individual host-parasite associations likely represent cospeciation links. Parasite colonization history was reconstructed, followed by an estimation of oscillation events and specificity level. The results indicate the presence of four Spauligodon clades in the Canary Islands, which originated from at least three different colonization events. We found evidence of host range oscillations to truly novel hosts, which in one case led to higher diversification. Contemporary host-parasite associations show strong host specificity, suggesting that changes in host breadth were limited to the shift period. Lineages with more frequent and wider taxonomic host range oscillations prior to the initial colonization event showed wider range oscillations during colonization and diversification within the archipelago. Our results suggest that a lineage's evolutionary past may be the best indicator of a parasite's potential for future range expansions.


Assuntos
Evolução Biológica , DNA Mitocondrial/genética , Oxyuroidea/genética , Filogenia , Animais , Teorema de Bayes , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita/genética , Oxyuroidea/patogenicidade , Espanha , Especificidade da Espécie
20.
J Parasitol ; 102(4): 476-80, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26835601

RESUMO

: Hemogregarines are the most-commonly reported hemoparasites in reptiles. In this work we analyzed samples from 572 individuals of 6 species of the wall gecko genus Tarentola from European and African countries adjacent to the Mediterranean Sea as well as from the Macaronesian islands. Screening was done using hemogregarine-specific primers for the 18S rRNA gene. Positive amplifications were sequenced so that the diversity of the hemogregarines from these hosts could be assessed within a phylogenetic framework. The results from the phylogenetic analysis showed that within Tarentola, the detected parasites are comprised of at least 4 distinct main lineages of Hepatozoon spp. In clades A and B, the new sequences clustered closely together with the ones previously known from individuals of the genus Tarentola and other species of geckos but also with those from other vertebrate host groups including skinks, snakes, iguanids, and rodents. Clade C included a sample from Tarentola angustimentalis of the Canary Islands. This sequence is the first molecular characterization of these hemogregarines in this archipelago. Until now, this lineage had only been found in lacertids, skinks, and snakes, so this infection extends the host range for this clade. Lastly, in the newly detected clade D, the retrieved parasite sequences form a group currently identified as exclusive of geckos. Our results show that geckos of Tarentola spp. harbor a great diversity of hemogregarines but also that further sampling and other tools, including a multi-locus approach using faster-evolving genetic markers, and identification of definitive hosts are needed to better understand the biology, diversity, and distribution of these parasites.


Assuntos
Coccidiose/veterinária , Eucoccidiida/genética , Variação Genética , Lagartos/parasitologia , Algoritmos , Animais , Açores , Teorema de Bayes , Cabo Verde , Coccidiose/parasitologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Eucoccidiida/classificação , Marcadores Genéticos , Funções Verossimilhança , Região do Mediterrâneo , Tipagem de Sequências Multilocus , Filogenia , RNA Ribossômico 18S/genética , Alinhamento de Sequência/veterinária , Espanha
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