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1.
J Vet Sci ; 19(2): 280-289, 2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29032656

RESUMO

The barn owl (BO) and the collared scops owl (CSO) are common nocturnal raptors throughout Thailand. Blood samples from 23 adult BOs and 14 CSOs were collected and processed for complete blood cell counts and parasite morphological examinations. Two Haemoproteus-positive samples were processed for ultrastructural observation. Polymerase chain reaction (PCR) analysis for a partial cytochrome b gene (cytb) from Haemoproteus was performed in all samples. Haemoproteus presence detected by light microscopy was lower than that detected by PCR (30.4% and 34.8%, respectively, in BO; and 50.0% and 78.6%, respectively, in CSO). Comparative hematology revealed that Haemoproteus-positive BOs had higher mean cell hemoglobin concentration, total leukocyte, absolute heterophil, basophil, and monocyte counts than Haemoproteus-negative BOs, but no significant differences between Haemoproteus-negative and -positive CSOs. Monocyte ultrastructure analysis revealed a role in the elimination of gametocytes. Morphologically, the Haemoproteus in 3 BOs and 6 CSOs were identified as H. noctuae, while that in 1 CSO was identified as H. syrnii. Phylogenetic analysis indicated the Haemoproteus spp. in 8 BOs and 7 CSOs were not closely related to H. noctuae or H. syrnii, and the cytb of 2 CSOs was that of H. syrnii. These results should be useful for study of Haemoproteus.


Assuntos
Doenças das Aves/parasitologia , Haemosporida , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/epidemiologia , Feminino , Haemosporida/genética , Haemosporida/ultraestrutura , Masculino , Microscopia/veterinária , Filogenia , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/epidemiologia , Tailândia/epidemiologia
2.
Parasit Vectors ; 10(1): 397, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28841905

RESUMO

BACKGROUND: Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. METHODS: Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. RESULTS: All investigated parasites completed sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete sporogony in C. impunctatus. CONCLUSIONS: Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels.


Assuntos
Ceratopogonidae/parasitologia , Haemosporida/fisiologia , Insetos Vetores/parasitologia , Animais , Teorema de Bayes , Doenças das Aves/parasitologia , Europa (Continente) , Feminino , Haemosporida/genética , Haemosporida/ultraestrutura , Insetos Vetores/fisiologia , Oocistos/fisiologia , Passeriformes/parasitologia , Filogenia , Reação em Cadeia da Polimerase , Esporozoítos/fisiologia
3.
Syst Parasitol ; 93(5): 431-49, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27220998

RESUMO

DNA barcoding (molecular characterisation) is a useful tool for describing the taxonomy and systematics of organisms. Over 250 species of avian haemosporidian parasites have been described using morphological characters, yet molecular techniques based on polymerase chain reaction (PCR) suggest this diversity is underestimated. Moreover, molecular techniques are particularly useful for the detection of chronic infections and tissue stages of these parasites. Species delimitation is problematic among haemosporidians, and many questions about the mechanisms and patterns of speciation, host specificity and pathogenicity are still unresolved. Accumulation of additional genetic and morphological information is needed to approach these questions. Here, we combine microscopic examination with PCR-based methods to develop molecular characterisation of Haemoproteus (Parahaemoproteus) manwelli Bennett, 1978 and Haemoproteus (Parahaemoproteus) gavrilovi Valkiunas & Iezhova, 1990, both of which parasitise the bee-eater Merops apiaster L. We also describe a new species, Haemoproteus (Parahaemoproteus) palloris n. sp., from the blood of the willow warbler Phylloscopus trochilus (L.). We performed phylogenetic analyses with a set of mitochondrial cytochrome b (cyt b) gene lineages, which have been linked to parasite morphospecies and are available in the MalAvi database. Our findings show that morphological characters, which have been traditionally used in the description of haemosporidians, exhibit phylogenetic congruence. This study contributes to a better understanding of avian haemosporidian diversity and provides new molecular markers (cyt b and apicoplast gene sequences) for the diagnostics of inadequately investigated haemosporidian infections.


Assuntos
Haemosporida/classificação , Haemosporida/genética , Animais , Apicoplastos/genética , Biodiversidade , Citocromos b/genética , DNA de Protozoário/genética , Haemosporida/ultraestrutura , Passeriformes/parasitologia , Filogenia , Especificidade da Espécie
5.
J Biol Chem ; 289(49): 33712-29, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25336639

RESUMO

I knew nothing and had thought nothing about parasites until 1971. In fact, if you had asked me before then, I might have commented that parasites were rather disgusting. I had been at the Johns Hopkins School of Medicine for three years, and I was on the lookout for a new project. In 1971, I came across a paper in the Journal of Molecular Biology by Larry Simpson, a classmate of mine in graduate school. Larry's paper described a remarkable DNA structure known as kinetoplast DNA (kDNA), isolated from a parasite. kDNA, the mitochondrial genome of trypanosomatids, is a DNA network composed of several thousand interlocked DNA rings. Almost nothing was known about it. I was looking for a project on DNA replication, and I wanted it to be both challenging and important. I had no doubt that working with kDNA would be a challenge, as I would be exploring uncharted territory. I was also sure that the project would be important when I learned that parasites with kDNA threaten huge populations in underdeveloped tropical countries. Looking again at Larry's paper, I found the electron micrographs of the kDNA networks to be rather beautiful. I decided to take a chance on kDNA. Little did I know then that I would devote the next forty years of my life to studying kDNA replication.


Assuntos
Replicação do DNA , DNA de Cinetoplasto/metabolismo , Kinetoplastida/metabolismo , DNA de Cinetoplasto/genética , DNA de Cinetoplasto/história , DNA de Cinetoplasto/ultraestrutura , Regulação da Expressão Gênica , Haemosporida/genética , Haemosporida/metabolismo , Haemosporida/ultraestrutura , História do Século XX , História do Século XXI , Kinetoplastida/genética , Kinetoplastida/ultraestrutura , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
6.
Parasite ; 21: 17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24759652

RESUMO

Haemoproteus ilanpapernai Karadjian and Landau n. sp. from the Spotted Wood Owl, Strix seloputo, in Singapore is described from material from Ilan Paperna's collection of slides. The species was previously identified as Haemoproteus syrnii (Mayer, 1910). However, comparisons between the material from Strix seloputo and our own material from Strix aluco, the type host of H. syrnii, revealed morphological and molecular differences. H. ilanpapernai n. sp. differs morphologically from H. syrnii by the much smaller size of the gametocytes, the different position of the mature gametocytes in the erythrocyte (apical, subapical, or lateral in H. ilanpapernai vs. always lateral in H. syrnii), the effect on the erythrocyte nucleus (frequently tilted in H. ilanpapernai but not displaced laterally vs. straight and displaced laterally in H. syrnii) and characters of the pigment (aggregated in the gametocytes of H. ilanpapernai vs. dispersed in H. syrnii). A molecular analysis showed that the two species differ by 2.9% at the cyt b and 3.1% at the COI genes.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/isolamento & purificação , Parasitemia/veterinária , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/epidemiologia , Citocromos b/genética , DNA de Protozoário/genética , Bases de Dados de Ácidos Nucleicos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Eritrócitos/parasitologia , Haemosporida/classificação , Haemosporida/genética , Haemosporida/ultraestrutura , Dados de Sequência Molecular , Parasitemia/epidemiologia , Parasitemia/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Proteínas de Protozoários/genética , Homologia de Sequência do Ácido Nucleico , Singapura/epidemiologia , Especificidade da Espécie
7.
Parasite ; 20: 32, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24029169

RESUMO

In France, Haemoproteus syrnii is frequently found in the Tawny Owl, Strix aluco. Additional and complementary features of this species, and in particular the characteristics of volutin, are presented. The authors consider the volutin granules as constant in a given species, and discuss their taxonomic value. These cytoplasmic inclusions appear early during the first stages of development of the gametocytes as an initial granule which multiplies as the parasite develops. They were reported in some species of Haemoproteus but are seldom considered as a specific character and described with precision. Sporogony from ookinete to apparently mature sporozoites appears to take place in a pupiparous hippoboscid (Ornithomyia sp.). One specimen was crushed between two slides and stained with Giemsa. Gametocytes of H. syrnii, many ookinetes, an immature oocyst and mature sporozoites were observed spread all over the smear. This would allow classifying this species in the Haemoproteus subgenus. We provide associated molecular data derived from the cyt b and cox 1 gene from this parasite. We discuss the problems of multiple infections and the difficulties in identifying Haemoproteus species and in deriving conclusions from sequences deposited in databases.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/epidemiologia , Núcleo Celular/ultraestrutura , Citocromos b/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Eritrócitos/parasitologia , Eritrócitos/ultraestrutura , Feminino , França/epidemiologia , Haemosporida/genética , Haemosporida/fisiologia , Haemosporida/ultraestrutura , Masculino , Dados de Sequência Molecular , Filogenia , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Esporos de Protozoários/fisiologia
8.
J Parasitol ; 99(1): 112-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22924909

RESUMO

Haemoproteus anatolicum n. sp. was identified in the tortoise Testudo graeca. The new species is described based on the morphology of its blood stages and a segment of the mitochondrial cytochrome b gene, which can be used for molecular identification and diagnosis. Chelonian haemoproteids recorded in the past were defined solely on the basis of their morphological characteristics. The chelonian haemoproteid we describe as a new species has a close genetic relationship to lizard haemoproteids, i.e., Haemoproteus ptyodactylii and Haemoproteus kopki. The new species description provides significant new information for little-known chelonian haemoproteids.


Assuntos
Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Tartarugas/parasitologia , Animais , DNA de Protozoário/sangue , DNA de Protozoário/química , Eritrócitos/parasitologia , Eritrócitos/patologia , Feminino , Haemosporida/genética , Haemosporida/ultraestrutura , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Turquia
9.
J Parasitol ; 99(3): 513-21, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23240808

RESUMO

Here we describe Haemoproteus (Haemoproteus) multivolutinus n. sp. from a tambourine dove (Turtur timpanistria) of Uganda and Haemoproteus (Haemoproteus) paramultipigmentatus n. sp. (Haemosporida, Haemoproteidae) from the Socorro common ground dove (Columbina passerina socorroensis) of Socorro Island, Mexico. These parasites are described based on the morphology of their blood stages and segments of the mitochondrial cytochrome b gene that can be used for molecular identification and diagnosis of these species. Gametocytes of H. multivolutinus possess rod-like pigment granules and are evenly packed with volutin, which masks pigment granules and darkly stains both macro- and microgametocytes in the early stages of their development. Based on these 2 characters, H. multivolutinus can be readily distinguished from other species of hemoproteids parasitizing columbiform (Columbiformes) birds. Haemoproteus paramultipigmentatus resembles Haemoproteus multipigmentatus; it can be distinguished from the latter parasite primarily due to the broadly ovoid shape of its young gametocytes and significantly fewer pigment granules in its fully developed gametocytes. We provide illustrations of blood stages of the new species, and phylogenetic analyses identify DNA lineages closely related to these parasites. Cytochrome b lineages of Haemoproteus multivolutinus and H. paramultipigmentatus cluster with hippoboscid-transmitted lineages of hemoproteids; thus these parasites likely belong to the subgenus Haemoproteus. We emphasize the importance of using cytochrome b sequences in conjunction with thorough microscopic descriptions to facilitate future identification of these and other avian hemosporidian species.


Assuntos
Doenças das Aves/parasitologia , Columbidae/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Citocromos b/genética , Eritrócitos/parasitologia , Haemosporida/genética , Haemosporida/ultraestrutura , México/epidemiologia , Dados de Sequência Molecular , Filogenia , Prevalência , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/epidemiologia , Uganda/epidemiologia
10.
Parasite ; 19(2): 137-46, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22550624

RESUMO

Four species of Haemoproteidae were found in Pteropus alecto Temminck, 1837 in Queensland, Australia: i) Johnsprentia copemani, Landau et al., 2012; ii) Sprattiella alecto gen. nov., sp. nov., characterised by schizonts in the renal vessels; iii) Hepatocystis levinei, Landau et al., 1985, originally described from Pteropus poliocephalus Temminck, 1825 and, experimentally from Culicoides nubeculosus and found in this new host and for which features of the hepatic schizonts are reported; iv) gametocytes of Hepatocystis sp. which are illustrated but cannot be assigned to a known species. A tentative interpretation of phylogenetic characters of haemosporidians of bats is provided from the morphology of the gametocytes and localisation of the tissue stages with respect to recent data on the phylogeny of bats.


Assuntos
Quirópteros/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Animais , Quirópteros/classificação , Diagnóstico Diferencial , Haemosporida/isolamento & purificação , Haemosporida/ultraestrutura , Rim/parasitologia , Fígado/parasitologia , Filogenia , Infecções Protozoárias em Animais/diagnóstico , Esquizontes/classificação , Esquizontes/ultraestrutura
11.
J Parasitol ; 96(6): 1197-203, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21158636

RESUMO

Inferences about the evolution of host-parasitic relationships are often made based on the prevalence of avian malaria, which is usually estimated in a large sample of birds using either microscopic or molecular screening of blood samples. However, different techniques often have variable accuracy; thus, screening methodology can raise issues about statistical bias if method sensitivity varies systematically across parasites or hosts. To examine this possibility, published information was collected on the prevalence of species in 4 genera of avian blood parasites ( Plasmodium, Haemoproteus, Leucocytozoon, and Trypanosoma) from various sources that used different tools. The data were tested to determine if the application of different methods provided different estimates for the same hosts. In these comparisons between the main methodologies, the PCR-based molecular methods were generally found to provide higher estimates for Plasmodium spp. prevalence than microscopic tools, while there was no significant tendency for such a trend in species of Haemoproteus and Leucocytozoon. When analyzing intraspecific variance of prevalence within molecular studies, some studies provided consistently higher estimates for Haemoproteus spp. prevalence than others, indicating that differences between studies can affect detected estimates. Within microscopic studies, surveys that examined more microscopic fields were more likely to report higher prevalence for Plasmodium spp. than those relying on fewer microscopic fields. Consequently, studies making comparisons across parasite genera and/or host species from different sources need to consider several types of bias originating from variation in method sensitivity.


Assuntos
Haemosporida/isolamento & purificação , Malária Aviária/epidemiologia , Microscopia/normas , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase/normas , Animais , Aves , Haemosporida/genética , Haemosporida/ultraestrutura , Malária Aviária/diagnóstico , Malária Aviária/parasitologia , Microscopia/métodos , Plasmodium/genética , Plasmodium/ultraestrutura , Reação em Cadeia da Polimerase/métodos , Prevalência , Infecções Protozoárias em Animais/diagnóstico , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Sensibilidade e Especificidade , Trypanosoma/genética , Trypanosoma/isolamento & purificação , Trypanosoma/ultraestrutura , Tripanossomíase/diagnóstico , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia , Tripanossomíase/veterinária
12.
J Parasitol ; 96(4): 783-92, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20486741

RESUMO

Haemoproteus (Haemoproteus) multipigmentatus n. sp. (Haemosporida, Haemoproteidae) was found in the endemic Galapagos dove Zenaida galapagoensis . It is described based on the morphology of its blood stages and segments of the mitochondrial cytochrome b gene, which can be used for molecular identification and diagnosis of this species. Haemoproteus multipigmentatus can be readily distinguished from all species of hemoproteids of the subgenus Haemoproteus , primarily due to numerous (approximately 40 on average) small pigment granules in its mature gametocytes. Illustrations of blood stages of the new species are given, and phylogenetic analysis identifies DNA lineages closely related to this parasite, which is prevalent in the Galapagos dove and also has been recorded in other species of Columbiformes in Mexico, Guatemala, and Peru, and so seems to be widespread in countries in the New World with warm climates. Cytochrome b lineages of H. multipigmentatus cluster with hippoboscid-transmitted lineages of Haemoproteus columbae . The same lineages of H. multipigmentatus were recorded in thoraxes of the hippoboscid fly Microlynchia galapagoensis , which likely is a natural vector of this parasite in Galapagos. Because different primers might amplify different parasites if they have a better match during a simultaneous infection, it is important that researchers standardize the genetic marker of choice for molecular typing of hemosporidian species. This study shows that more discussion among researchers is needed to clearly establish the sequence length and number of genes used for identification of hemosporidian parasites at different taxonomic levels. We point to the need of using both morphology and gene markers in studies of hemosporidian parasites, particularly in wildlife.


Assuntos
Doenças das Aves/parasitologia , Columbidae/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Animais , Sequência de Bases , Teorema de Bayes , Doenças das Aves/epidemiologia , Citocromos b/genética , DNA de Protozoário/química , Dípteros/parasitologia , Equador/epidemiologia , Haemosporida/genética , Haemosporida/ultraestrutura , Insetos Vetores/parasitologia , Dados de Sequência Molecular , Filogenia , Prevalência , Infecções Protozoárias em Animais/epidemiologia
13.
Parasitology ; 137(2): 217-27, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19765350

RESUMO

The blackcap (Sylvia atricapilla) is a common Palearctic migratory warbler, and haemosporidian parasites are common in this species. However, genetic and phenotypic diversity of haemosporidians in warblers has been insufficiently investigated and poorly linked. We addressed this issue by combining molecular and microscopy data for detection of pigment-forming haemosporidians of the genera Haemoproteus and Plasmodium. Blood samples from 498 blackcaps were collected at 7 different sites in Europe and investigated for these parasites by polymerase chain reaction (PCR)-based techniques and microscopic examination. In all, 56% of the birds were infected by at least 1 out of 25 distinct mitochondrial cytochrome b (cyt b) gene lineages of these haemosporidians. It is concluded that the blackcap is infected not only with blackcap specific haemosporidians, but also with Haemoproteus majoris, which is a host generalist and common in birds belonging to the Paridae. Haemoproteus pallidulus sp. nov. is described based on morphology of its blood stages and segments of the cyt b and dihydrofolate reductase/thymidylate synthase (DHFR-TS) genes. This study provides evidence that genetic diversity of haemosporidian parasites might be positively correlated with migratory strategies of their avian hosts; it also contributes to the value of both microscopy and molecular diagnostics of avian blood parasites.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/classificação , Haemosporida/ultraestrutura , Filogenia , Infecções Protozoárias em Animais/parasitologia , Aves Canoras/parasitologia , Animais , Citocromos b/genética , Eritrócitos/parasitologia , Europa (Continente) , Haemosporida/genética , Microscopia , Complexos Multienzimáticos/genética , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Especificidade da Espécie , Tetra-Hidrofolato Desidrogenase/genética , Timidilato Sintase/genética
14.
J Parasitol ; 96(1): 170-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19685938

RESUMO

The current taxonomy of leucocytozoids (Haemosporida, Leucocytozoidae) is based on the morphology of blood stages of the parasites and on limited information about their specificity. Recent molecular studies have revealed a remarkable genetic diversity of leucocytozoids, indicating that their taxonomic diversity may be greater than in the current classifications. We addressed this issue using morphological data and phylogenetic analysis of the cytochrome b gene of 14 positively identified species of avian haemosporidians. Based on the current taxonomy, Leucocytozoon toddi is the sole species of leucocytozoids parasitizing falconiform birds. However, several distinct haplotypes have been revealed in falconiform birds, suggesting that L. toddi might be a group of cryptic species. We investigated the morphology of blood stages of leucocytozoids of 2 haplotypes (2 lineages from Accipiter spp. and 3 lineages from Buteo spp.) and concluded that these parasites can be readily distinguished due to length of the cytoplasmic processes of their host cells; therefore, they do represent distinct morphospecies. Morphology of the cytoplasmic processes of host cells warrants more attention in the taxonomy of Leucocytozoon species. Leucocytozoon toddi indeed is a species group that currently includes Leucocytozoon mathisi, Leucocytozoon buteonis, and L. toddi; additional morphospecies can be added to this group in the future. It is probable that some other morphospecies of Leucocytozoon also might be groups of closely related species.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/classificação , Falcões/parasitologia , Infecções Protozoárias em Animais/parasitologia , Animais , Sequência de Bases , Citocromos b/genética , DNA de Protozoário/química , Eritrócitos/parasitologia , Haemosporida/genética , Haemosporida/ultraestrutura , Filogenia , Plasmodium/classificação , Plasmodium/genética
15.
J Parasitol ; 94(6): 1385-94, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19127967

RESUMO

In spite of their potential as model organisms and their medical importance, parasite speciation processes have been insufficiently discussed in the general literature. Scarcity of experimental data regarding reproductive isolation of parasites is a serious obstacle. Toward this end we developed a method for the investigation of hybridization of hemosporidian parasites in vitro. Five species of Haemoproteus (Haemosporida, Haemoproteidae) were isolated from naturally infected passerine birds. They were identified to species based on morphology of their gametocytes and PCR amplification of a segment of the parasite's mitochondrial cytochrome b gene. Hybridization of Haemoproteus spp. was initiated in vitro by mixing blood containing mature gametocytes of different species with a 3.7% solution of sodium citrate and exposure of the mixture to air. The following hybridization experiments were performed: (1) Haemoproteus minutus x Haemoproteus pallidus, (2) Haemoproteus balmorali x Haemoproteus tartakovskyi, and (3) Haemoproteus fringillae x H. tartakovskyi. The development of ookinetes of both species was blocked in the first experiment. Ookinetes of all species developed in other experiments, but presumed hybrids were distinguished only in the third experiment. Illustrations of ookinetes of all species are given. The present communication indicates that controlled experiments for direct hybridization of hemosporidians can be carried out in vitro. Such experimental research can be used to reconcile molecular and morphological data and to define biological species for this group of parasites.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/classificação , Hibridização Genética , Passeriformes/parasitologia , Infecções Protozoárias em Animais/parasitologia , Animais , Citocromos b/genética , Especiação Genética , Haemosporida/genética , Haemosporida/ultraestrutura , Parasitemia/parasitologia
16.
Parasitology ; 133(Pt 3): 279-88, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16740182

RESUMO

More than 200 species of avian Haemosporidia (genera Plasmodium, Haemoproteus, and Leucocytozoon) have been described based primarily on morphological characters seen in blood smears. Recent molecular studies, however, suggest that such methods may mask a substantial cryptic diversity of avian haemosporidians. We surveyed the haemosporidians of birds sampled at 1 site in Israel. Parasites were identified to species based on morphology, and a segment of the parasite's cytochrome b gene was sequenced. We compared 3 species concepts: morphological, genetic, and phylogenetic. Fifteen morphological species were present. Morphological species that occurred once within our dataset were associated with a unique gene sequence, displayed large genetic divergence from other morphological species, and were not contained within clades of morphological species that occurred more than once. With only 1 exception, morphological species that were identified from multiple bird hosts presented identical sequences for all infections, or differed by few synonymous substitutions, and were monophyletic for all phylogenetic analyses. Only the morphological species Haemoproteus belopolskyi did not follow this trend, falling instead into at least 2 genetically distant clades. Thus, except for H. belopolskyi, parasites identified to species by morphology were supported by both the genetic and phylogenetic species concepts.


Assuntos
Doenças das Aves/parasitologia , Citocromos b/genética , Haemosporida/classificação , Haemosporida/ultraestrutura , Infecções Protozoárias em Animais/parasitologia , Migração Animal , Animais , Aves , Primers do DNA/química , Haemosporida/genética , Haemosporida/isolamento & purificação , Israel , Dados de Sequência Molecular , Parasitemia/parasitologia , Parasitemia/veterinária , Filogenia , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
17.
J Parasitol ; 92(2): 375-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16729697

RESUMO

Species of Leucocytozoon (Haemosporida, Leucocytozoidae) traditionally have been described based on morphological characters of their blood stages and host cells, with limited information on their avian host specificity. Based on the current taxonomy, Leucocytozoon toddi is the sole valid species of leucocytozoids parasitizing falconiform birds. Using a nested polymerase chain reaction protocol, we determined the prevalence of Leucocytozoon infection in 5 species of diurnal raptors from California. Of 591 birds tested, 177 (29.9%) were infected with Leucocytozoon toddi. Subsequent phylogenetic analysis of the cytochrome b gene revealed that distinct haplotypes are present in hawks of these genera. Haplotypes present in Buteo spp. are not found in Accipiter spp., and there is a 10.9% sequence divergence between the 2 lineage clades. In addition, Leucocytozoon sp. from Accipiter spp. from Europe group more closely with parasites found in Accipiter spp. from California than the same California Accipiter species do with their sympatric Buteo spp. Similarly, a Leucocytozoon haplotype from a Common Buzzard (Buteo buteo) from Kazakhstan forms a monophyletic lineage with a parasite from B. jamaicensis from California. These results suggest that Leucocytozoon toddi is most likely a group of cryptic species, with 1 species infecting Buteo spp. and 1 or more species, or subspecies, infecting Accipiter spp.


Assuntos
Doenças das Aves/parasitologia , Falconiformes/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Animais , Países Bálticos/epidemiologia , Doenças das Aves/epidemiologia , California/epidemiologia , Ritmo Circadiano , Citocromos b/genética , DNA de Protozoário/química , Haemosporida/genética , Haemosporida/ultraestrutura , Cazaquistão/epidemiologia , Madagáscar/epidemiologia , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Análise de Sequência de DNA/veterinária
18.
Protist ; 157(1): 13-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16427806

RESUMO

Little is known regarding the ultrastructure of the genus Fallisia (Apicomplexa: Haemosporina: Garniidae). This report describes the fine structure of some developmental stages of Fallisia audaciosa that infect neutrophils in the peripheral blood of the Amazonian lizard Plica umbra (Reptilia: Iguanidae). The parasites lie within a parasitophorous vacuole and exhibit the basic structures of members of the Apicomplexa, such as the pellicle and the cytostome. Invaginations of the inner membrane complex were seen in the gametocytes and may be concerned with nutrition. The meronts were irregularly shaped before division, a feature unusual among members of the Apicomplexa. The unusual presence of a parasitic protozoan within neutrophils, in some way interfering with or modulating the microbicidal activity of such cells, is discussed.


Assuntos
Haemosporida/crescimento & desenvolvimento , Haemosporida/ultraestrutura , Iguanas/parasitologia , Neutrófilos/parasitologia , Infecções Protozoárias em Animais/parasitologia , Animais , Estágios do Ciclo de Vida , Microscopia Eletrônica de Transmissão
19.
J Parasitol ; 92(6): 1319-24, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17304814

RESUMO

A parasite's shift to a new host may have serious evolutionary consequences, since host switching usually is associated with a change in virulence and may lead to the evolution of emerging diseases. This phenomenon remains insufficiently studied in wildlife. Here, we combine microscopic examination of blood films and PCR-based methods to investigate the natural host specificity of Haemoproteus and Plasmodium spp. in birds of 4 families of the Passeriformes within a small geographic area. The material was collected on the Curonian Spit in the Baltic Sea between May and July in 2003-2004. A nested-PCR protocol was used for amplifying and sequencing a fragment of 480 nucleotides of the cytochrome b gene of the mtDNA of these parasites. Blood samples from 282 birds, which were positive both by microscopic examination of blood films and mtDNA amplification, were used in this study. We found that Haemoproteus majoris (lineages hPARUS1, hCCF5, hWW2, and hPHSIB1), Haemoproteus sp. (hWW1), Plasmodium (Haemamoeba) sp. (pSGS1), and Plasmodium (Haemamoeba) sp. (pGRW11) are capable of infecting birds belonging to different families of passeriform birds. Some species of Haemoproteus are less specific than have been traditionally believed. Haemoproteus majoris appears to have a genetic predisposition to have a broad host range. The level of host specificity varies markedly among different species of hemosporidian parasites of birds. The natural host range is thus not a reliable taxonomic character in the systematics of these parasites in the form in which it is still accepted in some recent taxonomic studies.


Assuntos
Citocromos b/genética , Haemosporida/fisiologia , Malária Aviária/parasitologia , Passeriformes/parasitologia , Animais , Sequência de Bases , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Haemosporida/classificação , Haemosporida/genética , Haemosporida/ultraestrutura , Interações Hospedeiro-Parasita , Malária Aviária/epidemiologia , Dados de Sequência Molecular , Parasitemia/parasitologia , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Especificidade da Espécie
20.
J Parasitol ; 92(6): 1336-43, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17304817

RESUMO

Using microscopy and PCR, we determined the prevalence of blood parasites in village chickens in Uganda and Cameroon. Of 148 individuals tested, 18.3% were infected with Leucocytozoon schoutedeni (Haemosporida, Leucocytozoidae) and 4.1% were infected with Trypanosoma gallinarum (Kinetoplastida, Trypanosomatidae). No other blood parasites were detected. Subsequent phylogenetic analysis of the cytochrome b gene of L. schoutedeni identified 2 distinct lineages that were found at all 3 sampling locations in Uganda. The sequence divergence between these 2 lineages is 1.5%. One of these lineages was also found in chickens in Cameroon, nearly 2,000 km distant. There are no morphological differences between blood stages of the parasites represented by the 2 different lineages, suggesting that cytochrome b gene sequence divergence can be as high as 1.5% within a single well-defined morphospecies of Leucocytozoon. We sequenced a portion of the small subunit ribosomal RNA gene (SSU rRNA) of T. gallinarum, and redescribe T. gallinarum for the first time since its discovery in 1911. These are the first assignments of DNA sequence data to these morphospecies of Leucocytozoon and Trypanosoma and may represent an example of intraspecific sequence divergence.


Assuntos
Galinhas/parasitologia , Haemosporida/classificação , Doenças das Aves Domésticas/parasitologia , Infecções Protozoárias em Animais/parasitologia , Trypanosoma/classificação , Tripanossomíase Africana/veterinária , Animais , Sequência de Bases , Camarões/epidemiologia , Citocromos b/genética , DNA de Cinetoplasto/química , DNA de Cinetoplasto/isolamento & purificação , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Variação Genética , Haemosporida/genética , Haemosporida/ultraestrutura , Dados de Sequência Molecular , Parasitemia/parasitologia , Parasitemia/veterinária , Filogenia , Doenças das Aves Domésticas/epidemiologia , Prevalência , Infecções Protozoárias em Animais/epidemiologia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Trypanosoma/genética , Trypanosoma/ultraestrutura , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/parasitologia , Uganda/epidemiologia
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