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1.
Parasitology ; 150(3): 221-229, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36268594

RESUMEN

Morphological traits from blood stages have been the gold standard for determining haemosporidian parasite species. However, the status of some taxa and the value of such traits in parasites from reptiles remain contentious. The scarce sampling of these species worsens the situation, and several taxa lack molecular data. A survey was performed in the Magdalena Department in Colombia, where 16 species of reptiles were captured. A peculiar haemosporidian parasite was found in the Turnip-tailed gecko Thecadactylus rapicauda. This haemosporidian does not show malarial pigment in blood stages under light microscopy; thus, it fits the Garnia genus's characters belonging to the Garniidae. However, the phylogenetic analyses using a partial sequence of cytochrome b and the mitochondrial DNA placed it within the Plasmodium clade. Our findings suggest that many putative Garnia species belong to the genus Plasmodium, like the one reported here. This study either shows that visible malarial pigment in blood stages is not a diagnostic trait of the genus Plasmodium or malarial pigment might be present in an undetectable form under a light microscope. In any case, the current taxonomy of haemosporidian parasites in reptiles requires revision. This study highlights the importance of using molecular and morphological traits to address taxonomic questions at the species and genus levels in haemosporidian parasites from reptiles.


Asunto(s)
Brassica napus , Haemosporida , Lagartos , Parásitos , Plasmodium , Animales , Filogenia , Plasmodium/genética , Serpientes , Haemosporida/genética
2.
Pathogens ; 10(2)2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33494428

RESUMEN

Determining the prevalence and local transmission dynamics of parasitic organisms are necessary to understand the ability of parasites to persist in host populations and disperse across regions, yet local transmission dynamics, diversity, and distribution of haemosporidian parasites remain poorly understood. We studied the prevalence, diversity, and distributions of avian haemosporidian parasites of the genera Plasmodium, Haemoproteus, and Leucocytozoon among resident and migratory birds in Serra do Mar, Brazil. Using 399 blood samples from 66 Atlantic Forest bird species, we determined the prevalence and molecular diversity of these pathogens across avian host species and described a new species of Haemoproteus. Our molecular and morphological study also revealed that migratory species were infected more than residents. However, vector infective stages (gametocytes) of Leucocytozoon spp., the most prevalent parasites found in the most abundant migrating host species in Serra do Mar (Elaenia albiceps), were not seen in blood films of local birds suggesting that this long-distance Austral migrant can disperse Leucocytozoon parasite lineages from Patagonia to the Atlantic Forest, but lineage sharing among resident species and local transmission cannot occur in this part of Brazil. Our study demonstrates that migratory species may harbor a higher diversity and prevalence of parasites than resident species, but transportation of some parasites by migratory hosts may not always affect local transmission.

3.
Int J Parasitol Parasites Wildl ; 9: 159-173, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31193389

RESUMEN

Avian communities from South America harbor an extraordinary diversity of Leucocytozoon species (Haemosporida, Leucocytozoidae). Here, of 890 birds sampled, 10 (1.2%) were infected with Leucocytozoon parasites. Among them, two new species were discovered and described. Leucocytozoon grallariae sp. nov. and Leucocytozoon neotropicalis sp. nov. were found in non-migratory highland passeriforms belonging to the Grallaridae and Cotingidae, respectively. They both possess gametocytes in fusiform host cells. However, due to combining microscopic examination and molecular detection, it was revealed that these parasites were present in co-infections with other Leucocytozoon species, which gametocytes develop in roundish host cells, therefore exhibiting two highly distant parasite lineages isolated from the same samples. Remarkably, the lineages obtained by cloning the mtDNA genomes were not captured by the classic nested PCR, which amplifies a short fragment of cytochrome b gene. Phylogenetic analyses revealed that the lineages obtained by the classic nested PCR clustered with parasites possessing gametocytes in roundish host cells, while the lineages obtained by the mtDNA genome PCR protocol were closely related to Leucocytozoon parasites possessing gametocytes in fusiform host cells. These findings suggest problems with the sensitivity of the molecular protocols commonly used to detect Leucocytozoon species. A detailed analysis of the primers used in the classic nested PCR revealed a match with DNA sequences from those parasites that possess gametocytes in roundish host cells (i.e., Leucocytozoon fringillinarum), while they differ with the orthologous regions in the mtDNA genomes isolated from the samples containing the two new species. Since these are mixed infections, none of the lineages detected in this study can be assigned accurately to the new Leucocytozoon morphospecies that develops in fusiform host cells. However, phylogenetic analyses allowed us to hypothesize their most probable associations. This study highlights the need for developing detection methods to assess the diversity of Leucocytozoon parasites accurately.

4.
Parasit Vectors ; 12(1): 40, 2019 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-30654841

RESUMEN

BACKGROUND: Haemoproteus and Plasmodium species are widespread avian blood parasites. Several Plasmodium species are known for their high virulence and have caused significant declines in naïve bird populations. The impact of closely related Haemoproteus parasites is largely unknown. Recently we reported a lethal disease in two parrot aviaries caused by Haemoproteus parasites. RESULTS: Here we show that the causative pathogen Haemoproteus minutus is responsible for further 17 lethal outbreaks in parrot aviaries in Denmark, Germany and Great Britain. All affected parrots are endemic to Australasia and South America. We sequenced the cytochrome b gene from megalomeront-infected muscle tissue of 21 parrots and identified the two lineages TUPHI01 and TURDUS2 as causative agents, commonly naturally infecting the common blackbird (Turdus merula) and the song thrush (Turdus philomelos), respectively, in the Palaearctic. No intraerythrocytic parasite stages were found in any of the parrots. We failed to detect H. minutus in invasive Indian ring-necked parakeets (Psittacula krameri) in Germany. Together this suggests that abortive infections with two virulent lineages of H. minutus are lethal for naïve parrot species from Australasia and South America. We asked whether we could detect H. minutus in New Zealand, where its Turdus hosts were introduced in the 1800s. We therefore tested invasive blackbirds and song thrushes, and the co-existing endemic red-fronted parakeet (Cyanoramphus novaezelandiae) population on three New Zealand islands. No Haemoproteus spp. DNA was detected in all blood samples, indicating absence of transmission. CONCLUSIONS: The results of this study show that captive parrots in Europe are threatened by two lineages of an otherwise benign parasite of Turdus spp. Aviary collections of parrots should be protected from Culicoides spp. vectors in Europe. Animal trade and climate changes extending the current vector and parasite distribution have to be considered as potential risk factors for the introduction of the disease in naïve parrot populations.


Asunto(s)
Enfermedades de las Aves/parasitología , Haemosporida/patogenicidad , Loros/parasitología , Infecciones Protozoarias en Animales/parasitología , Pájaros Cantores/parasitología , Animales , Australasia/epidemiología , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/transmisión , Citocromos b/genética , Europa (Continente)/epidemiología , Haemosporida/genética , Haemosporida/aislamiento & purificación , Músculos/parasitología , Filogenia , Infecciones Protozoarias en Animales/epidemiología , Infecciones Protozoarias en Animales/transmisión , Proteínas Protozoarias/genética , Análisis de Secuencia de ADN/veterinaria , América del Sur/epidemiología
5.
Mol Biol Evol ; 35(2): 383-403, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29126122

RESUMEN

Haemosporidians are a diverse group of vector-borne parasitic protozoa that includes the agents of human malaria; however, most of the described species are found in birds and reptiles. Although our understanding of these parasites' diversity has expanded by analyses of their mitochondrial genes, there is limited information on these genes' evolutionary rates. Here, 114 mitochondrial genomes (mtDNA) were studied from species belonging to four genera: Leucocytozoon, Haemoproteus, Hepatocystis, and Plasmodium. Contrary to previous assertions, the mtDNA is phylogenetically informative. The inferred phylogeny showed that, like the genus Plasmodium, the Leucocytozoon and Haemoproteus genera are not monophyletic groups. Although sensitive to the assumptions of the molecular dating method used, the estimated times indicate that the diversification of the avian haemosporidian subgenera/genera took place after the Cretaceous-Paleogene boundary following the radiation of modern birds. Furthermore, parasite clade differences in mtDNA substitution rates and strength of negative selection were detected. These differences may affect the biological interpretation of mtDNA gene lineages used as a proxy to species in ecological and parasitological investigations. Given that the mitochondria are critically important in the parasite life cycle stages that take place in the vector and that the transmission of parasites belonging to particular clades has been linked to specific insect families/subfamilies, this study suggests that differences in vectors have affected the mode of evolution of haemosporidian mtDNA genes. The observed patterns also suggest that the radiation of haemosporidian parasites may be the result of community-level evolutionary processes between their vertebrate and invertebrate hosts.


Asunto(s)
Evolución Biológica , Genoma Mitocondrial , Genoma de Protozoos , Haemosporida/genética , Selección Genética
6.
Malar J ; 16(1): 83, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28212654

RESUMEN

BACKGROUND: The role of zoos in conservation programmes has increased significantly in last decades, and the health of captive animals is essential to guarantee success of such programmes. However, zoo birds suffer from parasitic infections, which often are caused by malaria parasites and related haemosporidians. Studies determining the occurrence and diversity of these parasites, aiming better understanding infection influence on fitness of captive birds, are limited. METHODS: In 2011-2015, the prevalence and diversity of Plasmodium spp. and Haemoproteus spp. was examined in blood samples of 677 captive birds from the São Paulo Zoo, the largest zoo in Latin America. Molecular and microscopic diagnostic methods were used in parallel to detect and identify these infections. RESULTS: The overall prevalence of haemosporidians was 12.6%. Parasites were mostly detected by the molecular diagnosis, indicating that many birds harbour subclinical or abortive infections. In this project, birds of 17 orders (almost half of all the orders currently accepted in taxonomy of birds), 29 families, and 122 species, were tested, detecting positive individuals in 27% of bird species. Birds from the Anatidae were the most prevalently infected (64.7% of all infected animals). In all, infections with parasites of the genus Plasmodium (overall prevalence 97.6%) predominated when compared to those of the genus Haemoproteus (2.4%). In total, 14 cytochrome b (cytb) lineages of Plasmodium spp. and 2 cytb lineages of Haemoproteus spp. were recorded. Eight lineages were new. One of the reported lineages was broad generalist while others were reported in single or a few species of birds. Molecular characterization of Haemoproteus ortalidum was developed. CONCLUSION: This study shows that many species of birds are at risk in captivity. It is difficult to stop haemosporidian parasite transmission in zoos, but is possible to reduce the infection rate by treating the infected animals or/and while keeping them in facilities free from mosquitoes. Protocols of quarantine should be implemented whenever an animal is transferred between bird maintaining institutions. This is the first survey of haemosporidians in captive birds from different orders maintained in zoos. It is worth emphasizing the necessity of applying practices to control these parasites in management and husbandry of animals in captivity.


Asunto(s)
Animales de Zoológico , Enfermedades de las Aves/epidemiología , Aves , Haemosporida/aislamiento & purificación , Malaria Aviar/epidemiología , Animales , Enfermedades de las Aves/parasitología , Brasil/epidemiología , Ciudades/epidemiología , Citocromos b/genética , Haemosporida/clasificación , Malaria Aviar/parasitología , Filogenia , Plasmodium/clasificación , Plasmodium/aislamiento & purificación , Prevalencia , Proteínas Protozoarias/genética , Análisis de Secuencia de ADN
7.
J Anim Ecol ; 85(5): 1234-45, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27177277

RESUMEN

Understanding how parasites fill their ecological niches requires information on the processes involved in the colonization and exploitation of unique host species. Switching to hosts with atypical attributes may favour generalists broadening their niches or may promote specialization and parasite diversification as the consequence. We analysed which blood parasites have successfully colonized hummingbirds, and how they have evolved to exploit such a unique habitat. We specifically asked (i) whether the assemblage of Haemoproteus parasites of hummingbirds is the result of single or multiple colonization events, (ii) to what extent these parasites are specialized in hummingbirds or shared with other birds and (iii) how hummingbirds contribute to sustain the populations of these parasites, in terms of both prevalence and infection intensity. We sampled 169 hummingbirds of 19 species along an elevation gradient in Southern Ecuador to analyse the host specificity, diversity and infection intensity of Haemoproteus by molecular and microscopy techniques. In addition, 736 birds of 112 species were analysed to explore whether hummingbird parasites are shared with other birds. Hummingbirds hosted a phylogenetically diverse assemblage of generalist Haemoproteus lineages shared with other host orders. Among these parasites, Haemoproteus witti stood out as the most generalized. Interestingly, we found that infection intensities of this parasite were extremely low in passerines (with no detectable gametocytes), but very high in hummingbirds, with many gametocytes seen. Moreover, infection intensities of H. witti were positively correlated with the prevalence across host species. Our results show that hummingbirds have been colonized by generalist Haemoproteus lineages on multiple occasions. However, one of these generalist parasites (H. witti) seems to be highly dependent on hummingbirds, which arise as the most relevant reservoirs in terms of both prevalence and gametocytaemia. From this perspective, this generalist parasite may be viewed as a hummingbird specialist. This challenges the current paradigm of how to measure host specialization in these parasites, which has important implications to understand disease ecology.


Asunto(s)
Evolución Biológica , Aves/parasitología , Haemosporida/fisiología , Especificidad del Huésped , Animales , Enfermedades de las Aves/parasitología , Reservorios de Enfermedades/parasitología , Reservorios de Enfermedades/veterinaria , Ecuador , Infecciones Protozoarias en Animales/parasitología
8.
Acta Trop ; 159: 83-94, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26995696

RESUMEN

The great diversity of birds and ecosystems in the Andean mountains has been understudied in terms of their parasite species. We describe a new Haemoproteus parasite, H. (Parahaemoproteus) erythrogravidus infecting Zonotrichia capensis (Rufous-Collared Sparrow) in South America. The description of this blood parasite species is supported by morphological and molecular data based on a fragment of cytochrome b gene (cyt b) and complete mitochondrial genome sequences. The new species is closely related to H. (Parahaemoproteus) coatneyi, and it can be readily distinguished from the latter parasite due to morphology of its blood stages, particularly 1) the formation of a marked protrusion on envelope of infected erythrocytes by the majority of developing gametocytes, a feature which is unique for this Haemoproteus species and 2) the extremely attenuated width of the growing dumbbell-shaped macro- and microgametocytes. Additionally, Haemoproteus erythrogravidus is shown to be a monophyletic taxon that diverges from Haemoproteus coatneyi at the molecular level. We provide the complete mitochondrial DNA genome for both H. coatneyi and H. erythrogravidus. Molecular and morphological evidences indicate that H. erythrogravidus is present in Ecuador and Colombia, and genetic lineages with 100% of identity for the cyt b gene were reported in Chile, Perú, and Venezuela. Our study also indicates that H. erythrogravidus and H. coatneyi are sympatric sister taxa sharing Z. capensis as a host species across its distribution, which could be the result of sympatric speciation or complex biogeographic processes. Further studies on the distribution and evolutionary history of Z. capensis and its parasites H. erythrogravidus and H. coatneyi insight for our better understanding of the factors and dynamics driving parasite speciation.


Asunto(s)
Enfermedades de las Aves/parasitología , Aves/parasitología , ADN Protozoario/genética , Haemosporida/clasificación , Haemosporida/genética , Parásitos/clasificación , Infecciones Protozoarias en Animales/parasitología , Animales , Citocromos b/genética , ADN Mitocondrial , Genoma Mitocondrial , Filogenia , América del Sur
9.
Parasitol Res ; 115(4): 1443-52, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26677094

RESUMEN

Numerous studies addressed the diversity of bird Plasmodium and Haemoproteus parasites. However, a few have been carried out in continental avian hotspot regions such as Brazil, a country with markedly different biomes, including Amazon, Brazilian Savanna, Atlantic Forest, Caatinga, Pantanal, and Pampas. We present the first study on hemosporidian (Haemosporida) parasites in free-living birds from an Atlantic Forest fragment where more than 80 avian species have been reported. Within this area, the São Paulo Zoo locates, and it is the fourth largest zoo in the world and the largest in Latin America. A total of 133 free-living bird samples representing 12 species were collected in the zoo, with the overall hemosporidian prevalence of 18 % by PCR-based diagnostics. Twenty-four positive PCR signals were reported from four different bird species, including migratory ones. Columba livia, an urban species, considered nowadays a pest in big cities, showed 100 % prevalence of Haemoproteus spp., mainly Haemoproteus columbae. We discuss the epidemiological importance of new parasites introduced by migratory birds in the São Paulo Zoo area and the risk it poses to the captive species, which are natives or exotics. We also warn about the influence these parasites can have on the biodiversity and the structure of host populations by altering the competitive interaction between the free-living and the captive birds.


Asunto(s)
Enfermedades de las Aves/parasitología , Haemosporida/aislamiento & purificación , Infecciones Protozoarias en Animales/parasitología , Animales , Enfermedades de las Aves/epidemiología , Aves/parasitología , Brasil/epidemiología , Haemosporida/genética , Filogenia , Infecciones Protozoarias en Animales/epidemiología
10.
Exp Parasitol ; 157: 163-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26297677

RESUMEN

The evolutionary origin of wildlife and human malaria parasites (Plasmodium spp.) has been discussed for several decades. The lack of genomic data about species of wildlife haemosporidian parasites related to Plasmodium limits the number of taxa available for phylogenetic analysis. Genomic data about avian parasites of the genus Haemoproteus parasites, the sister genus to Plasmodium are still not available, mainly due to difficulties in obtaining pure DNA of parasites inhabiting nucleated avian host cells. Recent studies show that microgametes of Haemoproteus (Parahaemoproteus) spp. develop in vitro and can be isolated by simple centrifugation, allowing the isolation of pure parasite DNA for genomic studies. However, in vitro development of Haemoproteus (Haemoproteus) spp. has not been investigated, and it is unclear if microgametes of these parasites also can be obtained under in vitro conditions. Here, we provide the first data about the in vitro development of Haemoproteus (Haemoproteus) columbae, a widespread avian haemosporidian parasite, which is specific to pigeons and doves (Columbiformes) and is transmitted by hippoboscid flies (Diptera, Hippoboscidae). In vitro gametogenesis and ookinete development of H. columbae were studied using a strain isolated from a feral Rock Pigeon (Columba livia) in Bogotá-Colombia. The morphological events leading to exflagellation, fertilization and ookinete formation, as well as the rate of development of these stages were followed in vitro at 40 °C, 19 °C and 15 °C for 48 h. Macrogametes, microgametes, zygotes and initial stages of ookinete development were observed in all temperatures, but mature ookinetes were seen only at 40 °C. The largest diversity of sporogonic stages of H. columbae were present at 40 °C however, exflagellation, fertilization of macrogametes and development of immature ookinetes were also observed at 15 °C and 19 °C. Morphological and morphometric features of these stages in vitro were described and illustrated. This study demonstrates a requirement of high temperature for the successful development of mature ookinetes of H. columbae, but not gametes. We show that 1) parasites of the H. (Haemoproteus) subgenus exflagellate in vitro at 15-19 °C, as is the case in H. (Parahaemoproteus) spp. and 2) in vitro exflagellation can be used to obtain pure DNA for genomic studies.


Asunto(s)
Enfermedades de las Aves/parasitología , Columbidae/parasitología , Haemosporida/crecimiento & desarrollo , Infecciones Protozoarias en Animales/parasitología , Animales , Enfermedades de las Aves/sangre , Enfermedades de las Aves/epidemiología , Colombia/epidemiología , Haemosporida/genética , Datos de Secuencia Molecular , Prevalencia , Infecciones Protozoarias en Animales/sangre , Infecciones Protozoarias en Animales/epidemiología
11.
Parasitol Res ; 114(3): 1031-44, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25544705

RESUMEN

We describe morphologically unique Leucocytozoon pterotenuis sp. nov. (Haemosporida, Leucocytozoidae), the first reported leucocytozoid species developing in fusiform host cell found in a Neotropical passeriform bird. The type host of this parasite is the Chestnut-crowned Antpitta (Grallaria ruficapilla, Grallariidae), an elusive native passerine bird whose natural history remains, to a large degree, unexplored. This bird was captured in Palacio forest in the damping zone of Chingaza National Natural Park, Cundinamarca, Colombia, at 2900 m above sea level (asl). Gametocytes of the new species develop both in roundish and fusiform host cells. This parasite is readily morphologically distinguishable from the described Leucocytozoon species because its host cells possess the narrow (needle-like) spindle-shaped processes, which length markedly exceeds their width. Additionally, the host cell nucleus markedly extends into the processes. Phylogenetic relationships were constructed based on a fragment of the mitochondrial cytochrome b gene and the complete mitochondrial genome. Phylogenetic analysis placed the lineage of L. pterotenuis in different positions depending on the length of the sequence analyzed that is likely due to poor sampling of Leucocytozoon species, especially from rare or non-passerine hosts, as well as a paucity of complete mitochondrial sequences of these parasites. Available data indicate that Leucocytozoon parasites are distributed mainly in mountain regions of the Neotropics where unique morphological forms have been recently discovered. To a better knowledge of the diversity of Leucocytozoon spp. and their host-vector-parasite interactions in Neotropical countries, additional deep and intensive samplings are needed, particularly in orders different to Passeriformes.


Asunto(s)
Enfermedades de las Aves/parasitología , Haemosporida/clasificación , Passeriformes/parasitología , Infecciones Protozoarias en Animales/parasitología , Animales , Enfermedades de las Aves/epidemiología , Colombia/epidemiología , Citocromos b/genética , Genoma Mitocondrial/genética , Haemosporida/citología , Haemosporida/genética , Filogenia , Infecciones Protozoarias en Animales/epidemiología , Especificidad de la Especie
12.
Parasitol Res ; 113(8): 2991-3000, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24908432

RESUMEN

During a surveillance programme on avian influenza in wild birds in the east of Colombia, 42% of examined wild black-bellied whistling ducks (Dendrocygna autumnalis) were infected with undescribed Haemoproteus sp., which macrogametocytes possess one or several huge (2.5 µm in largest diameter) conspicuous roundish vacuoles, a unique character of avian haemoproteids. This parasite is named Haemoproteus (Parahaemoproteus) macrovacuolatus and described here using data on the morphology of its gametocytes, host cells and sequences of the complete mitochondrial genome and cytochrome b fragments. Illustrations of blood stages of the new species and DNA sequence information are provided. The phylogenetic analysis identified a closely related lineage C033, reported in South Asian ducks belonging to Dendrocygna. We also found that all Haemoproteus lineages from Passeriformes conformed a monophyletic group. Whereas we cannot exclude that this pattern could be an artefact of the limited taxonomic sampling in non-passeriform birds, thus this finding is worthy of attention. This study adds to our knowledge of the phylogenetic relationships among species of avian haemoproteids and describes a new haemoparasite in a non-passerine host.


Asunto(s)
Patos/parasitología , Haemosporida/citología , Haemosporida/genética , Filogenia , Animales , Enfermedades de las Aves/parasitología , Colombia , Citocromos b/genética , ADN Protozoario/genética , Genoma Mitocondrial , Haemosporida/clasificación , Infecciones Protozoarias en Animales/parasitología , Análisis de Secuencia de ADN
13.
Parasitol Res ; 113(2): 457-68, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24265056

RESUMEN

We describe Leucocytozoon quynzae sp. nov. (Haemosporida, Leucocytozoidae), which is the first Leucocytozoon parasite identified to species level in hummingbirds. It was found in the Amethyst-throated Sunangel (Heliangelus amethysticollis, Trochilidae, Apodiformes) captured in the Palacio Forest, which belongs to the damping zone of Chingaza National Natural Park, Cundinamarca, Colombia, at 2,900 m above sea level where the transmission occurs; the new species were found both in the high Andean forest and Paramo ecosystem. This parasite is described based on the morphology of its blood stages, a fragment of the mitochondrial cytochrome b gene, and the complete mitochondrial genome. Illustrations of blood stages of the new species are given, and the phylogenetic analysis places this lineage in a well-supported clade with other lineages of unidentified to species level leucocytozoids reported in the Trochilidae birds elsewhere. The new species possess gametocytes in roundish host cells; it can be readily distinguished from other similar leucocytozoids, primarily due to (1) a comma-like shape of the host cell nucleus, which extended one half or less of the circumference of the gametocyte and (2) a large number of prominent volutin granules in the cytoplasm. Identical mitochondrial cytochrome b sequence of Leucocytozoon quynzae was found in different hummingbird species at the type locality and also was reported in one passerine bird at the highlands of Peru. Leucocytozoon quynzae is the first leucocytozoid parasite described from South American birds; its transmission occurs both at low temperatures and high elevations. We discuss some patterns of distribution of avian leucocytozoids in South America and the role of Gigantodax spp. (Diptera, Simuliidae) as potential vectors of Leucocytozoon parasites in the Andean Region.


Asunto(s)
Enfermedades de las Aves/parasitología , Aves/parasitología , Haemosporida/clasificación , Haemosporida/aislamiento & purificación , Infecciones Protozoarias en Animales/parasitología , Animales , Enfermedades de las Aves/transmisión , Colombia , Citocromos b/genética , ADN Protozoario/sangre , ADN Protozoario/genética , Femenino , Genoma Mitocondrial , Haemosporida/citología , Haemosporida/genética , Insectos Vectores/parasitología , Masculino , Filogenia , Infecciones Protozoarias en Animales/transmisión , Simuliidae/parasitología , América del Sur
14.
Parasitol Res ; 112(12): 4193-204, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24048707

RESUMEN

Plasmodium (Novyella) unalis sp. nov. was found in the Great Thrush, Turdus fuscater (Passeriformes, Turdidae) in Bogotá, Colombia, at 2,560 m above sea level where the active transmission occurs. This parasite is described based on the morphology of its blood stages and a fragment of the mitochondrial cytochrome b gene (lineage UN227). Illustrations of blood stages of new species are given, and the phylogenetic analysis identifies closely related species and lineages of avian malaria parasites. The new species is most similar to Plasmodium (Novyella) vaughani (lineage SYAT05), a cosmopolitan avian malaria parasite; these parasites are also closely related genetically, with a genetic difference of 3.2% between them. P. unalis can be readily distinguished from the latter species morphologically, primarily due to the (1) presence of a single large, circular shaped pigment granule in the erythrocytic trophozoites and meronts; (2) presence of prominent vacuoles in trophozoites and growing meronts; and (3) presence of predominantly fan-like shaped erythrocytic meronts. Cytochrome b lineages with high similarity to the new species have been reported in Costa Rica, Brazil, Chile, and USA. It is probable that the new species of malaria parasite is widely distributed in the New World. This parasite has been reported only in the Great Thrush at the study site and might have a narrow range of avian hosts. Records of P. unalis are of particular theoretical interest due to its active transmission at highlands in Andes. Possible influence of urbanization on transmission of this malaria parasite in Bogotá is discussed.


Asunto(s)
Malaria Aviar/parasitología , Filogenia , Plasmodium/clasificación , Pájaros Cantores/parasitología , Altitud , Animales , Colombia , Citocromos b/genética , Eritrocitos/parasitología , Genes Mitocondriales , Genes Protozoarios , Plasmodium/citología , Plasmodium/genética
15.
J Parasitol ; 99(3): 513-21, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23240808

RESUMEN

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.


Asunto(s)
Enfermedades de las Aves/parasitología , Columbidae/parasitología , Haemosporida/clasificación , Infecciones Protozoarias en Animales/parasitología , Animales , Enfermedades de las Aves/sangre , Enfermedades de las Aves/epidemiología , Citocromos b/genética , Eritrocitos/parasitología , Haemosporida/genética , Haemosporida/ultraestructura , México/epidemiología , Datos de Secuencia Molecular , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/sangre , Infecciones Protozoarias en Animales/epidemiología , Uganda/epidemiología
16.
J Parasitol ; 99(2): 270-6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23043349

RESUMEN

The Socorro dove Zenaida graysoni , endemic to Socorro Island, was last reported in the wild in 1972. Fortunately, the species has been propagated in zoos in Europe and the United States, and plans are under way to re-introduce it to its native habitat. This will be the first known attempt to return a bird species extinct in the wild to its ancestral island. In order to assess the disease threats the Socorro dove may face, the avifauna of Socorro Island, with a specific focus on Socorro ground doves Columbina passerina socorroensis and mourning doves Zenaida macroura , as well as Socorro doves in captivity, were screened for blood parasites of the genera Plasmodium , Haemoproteus, Leucocytozoon, and Trypanosoma spp. We found Haemoproteus spp. in 17 (74%) of 23 Socorro ground doves, 23 (92%) of 25 mourning doves, and 3 (14%) of 21 northern mockingbirds; none of the other bird species showed infections. Here, we report the phylogenetic analysis of 19 distinct lineages of Haemoproteus spp. detected in birds of Socorro Island and compare their evolutionary relationships to parasites detected in the avifauna of the Galápagos Islands, continental Latin America, and Europe. Microscopic examination revealed 1 mourning dove infected with Plasmodium ( Haemamoeba ), thus underscoring the importance of using both PCR and microscopy when analyzing avian blood samples for hemosporidian parasites. The study confirms that the Socorro dove will most likely be exposed to Haemoproteus spp. that currently infect mourning doves and Socorro ground doves of Socorro Island. A monitoring program for both birds and vectors should be implemented to establish the prevalence of Plasmodium sp. and as a necessary conservation measure for critically endangered birds on the island.


Asunto(s)
Biodiversidad , Enfermedades de las Aves/parasitología , Columbidae/parasitología , Haemosporida/clasificación , Filogenia , Infecciones Protozoarias en Animales/parasitología , Animales , Animales de Zoológico , Enfermedades de las Aves/epidemiología , Aves , Extinción Biológica , Haemosporida/genética , Islas/epidemiología , México/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Infecciones Protozoarias en Animales/epidemiología
17.
Int J Parasitol Parasites Wildl ; 2: 286-91, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24533348

RESUMEN

Plasmodium (Novyella) nucleophilum was identified using microscopy and PCR, in an Egyptian Goose (Alopochen aegyptiacus) that died in São Paulo Zoo, Brazil. This parasite is characterized by elongated gametocytes, small meronts with scant cytoplasm, less than eight merozoites and mainly for having all the stages appressed to the nuclei of infected erythrocytes. Additionally, Plasmodium (Haemamoeba) sp. was identified by microscopy in the same blood sample. The latter parasite lacks nucleophilic blood stages and is characterized by large roundish trophozoites, each with a large prominent centrally collated vacuole. This co-infection was not confirmed by PCR amplification of the mitochondrial cytochrome b (cytb) gene and sequencing; only one Plasmodium sp. cytb sequence was detected in the blood sample. Since parasitemia of P. nucleophilum (2.4%) was much higher than that of P. (Haemamoeba) sp. (0.2%), PCR may have favored the amplification of the cytb sequence of the former. Phylogenetic analysis is in agreement with this conclusion because the reported cytb sequence was positioned in the same branch of sequences of several Novyella species. This is the first assignment of the mitochondrial cytb gene sequence to P. nucleophilum. The P. (Haemamoeba) parasite is particularly similar to Plasmodium (Haemamoeba) tejerai, because its advanced trophozoites and young erythrocytic meronts possess a large vacuole with prominent pigment granules arranged around it, the characteristic features of development in this species. For definitive identification of P. (Haemamoeba) species, mature meronts and gametocytes are required; however, these were absent from the thin blood smear. Representative images of the blood stages of P. nucleophilum and P. (Haemamoeba) sp. are provided. Together with microscopy data, the P. nucleophilum cytb sequence will assist in molecular identification (barcoding) of this Plasmodium species in other birds.

18.
Parasitol Int ; 62(2): 165-71, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23269202

RESUMEN

This study is the first report on mortality of Spheniscus magellanicus, penguin of South America, caused by Plasmodium tejerai, which was identified using morphological and molecular analyses. Blood stages (trophozoites, meronts and gametocytes) were reported and illustrated. The necropsy revealed marked splenomegaly and pulmonary edema, as well as moderate hepatomegaly and hydropericardium. The histopathology revealed the presence of tissue meronts in the macrophages and endothelial cells of multiple organs. The molecular analyses showed 5.6% of genetic divergence in cytochrome b gene between P. tejerai and Plasmodium relictum. Morphology of blood and tissue stages of P. tejerai is similar to P. relictum; the distinction between these two species requires experience in the identification of avian Plasmodium species. Molecular studies associated with reliably identified morphological species are useful for barcoding and comparisons with previous studies of wildlife malaria infections as well as for posterior phylogenetic and phylogeographic studies. S. magellanicus is a new host record of P. tejerai, which is the virulent parasite and worth more attention in avian conservation and veterinary medicine projects in South America.


Asunto(s)
Malaria Aviar/parasitología , Plasmodium/aislamiento & purificación , Spheniscidae/parasitología , Animales , Secuencia de Bases , Brasil , Citocromos b/genética , ADN Protozoario/química , ADN Protozoario/genética , Células Endoteliales/parasitología , Resultado Fatal , Macrófagos/parasitología , Malaria Aviar/sangre , Malaria Aviar/patología , Mitocondrias/metabolismo , Datos de Secuencia Molecular , Miocardio/patología , Parasitemia , Filogenia , Plasmodium/clasificación , Plasmodium/citología , Plasmodium/genética , Proteínas Protozoarias/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
19.
J Parasitol ; 98(4): 847-54, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22324933

RESUMEN

Haemoproteus (Haemoproteus) jenniae n. sp. (Haemosporida: Haemoproteidae) is described from a Galapagos bird, the swallow-tailed gull Creagrus furcatus (Charadriiformes, Laridae), based on the morphology of its blood stages and segments of the mitochondrial cytochrome b (cyt b) gene. The most distinctive features of H. jenniae development are the circumnuclear gametocytes occupying all cytoplasmic space in infected erythrocytes and the presence of advanced, growing gametocytes in which the pellicle is closely appressed to the erythrocyte envelope but does not extend to the erythrocyte nucleus. This parasite is distinguishable from Haemoproteus larae, which produces similar gametocytes and parasitizes closely related species of Laridae. Haemoproteus jenniae can be distinguished from H. larae primarily due to (1) the predominantly amoeboid outline of young gametocytes, (2) diffuse macrogametocyte nuclei which do not possess distinguishable nucleoli, (3) the consistent size and shape of pigment granules, and (4) the absence of rod-like pigment granules from gametocytes. Additionally, fully-grown gametocytes of H. jenniae cause both the marked hypertrophy of infected erythrocytes in width and the rounding up of the host cells, which is not the case in H. larae. Phylogenetic analyses identified the DNA lineages that are associated with H. jenniae and showed that this parasite is more closely related to the hippoboscid-transmitted (Hippoboscidae) species than to the Culicoides spp.-transmitted (Ceratopogonidae) species of avian hemoproteids. Genetic divergence between morphologically well-differentiated H. jenniae and the hippoboscid-transmitted Haemoproteus iwa, the closely related parasite of frigatebirds (Fregatidae, Pelecaniformes), is only 0.6%; cyt b sequences of these parasites differ only by 1 base pair. This is the first example of such a small genetic difference in the cyt b gene between species of the subgenus Haemoproteus. In a segment of caseinolytic protease C gene (ClpC), genetic divergence is 4% between H. jenniae and H. iwa. This study corroborates the conclusion that hippoboscid-transmitted Haemoproteus parasites infect not only Columbiformes birds but also infect marine birds belonging to Pelecaniformes and Charadriiformes. We conclude that the vertebrate host range should be used cautiously in identification of subgenera of avian Haemoproteus species and that the phylogenies based on the cyt b gene provide evidence for determining the subgeneric position of avian hemoproteids.


Asunto(s)
Enfermedades de las Aves/parasitología , Charadriiformes/parasitología , Dípteros/parasitología , Haemosporida/clasificación , Insectos Vectores/parasitología , Infecciones Protozoarias en Animales/parasitología , Animales , Secuencia de Bases , Teorema de Bayes , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/transmisión , ADN Protozoario/química , Ecuador/epidemiología , Eritrocitos/parasitología , Variación Genética , Haemosporida/genética , Haemosporida/fisiología , Funciones de Verosimilitud , Datos de Secuencia Molecular , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/epidemiología , Infecciones Protozoarias en Animales/transmisión , Caracteres Sexuales
20.
Mem Inst Oswaldo Cruz ; 106 Suppl 1: 3-11, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21881752

RESUMEN

Avian malaria parasites (Plasmodium) have a worldwide distribution except for Antarctica. They are transmitted exclusively by mosquito vectors (Diptera: Culicidae) and are of particular interest to health care research due to their phylogenetic relationship with human plasmodia and their ability to cause avian malaria, which is frequently lethal in non-adapted avian hosts. However, different features of avian Plasmodium spp, including their taxonomy and aspects of their life-history traits, need to be examined in more detail. Over the last 10 years, ecologists, evolutionary biologists and wildlife researchers have recognized the importance of studying avian malaria parasites and other related haemosporidians, which are the largest group of the order Haemosporida by number of species. These studies have included understanding the ecological, behavioral and evolutionary aspects that arise in this wildlife host-parasite system. Molecular tools have provided new and exiting opportunities for such research. This review discusses several emerging topics related to the current research of avian Plasmodium spp and some related avian haemosporidians. We also summarize some important discoveries in this field and emphasize the value of using both polymerase chain reaction-based and microscopy-based methods in parallel for wildlife studies. We will focus on the genus Plasmodium, with an emphasis on the distribution and pathogenicity of these parasites in wild birds in Brazil.


Asunto(s)
Culicidae/parasitología , Insectos Vectores/parasitología , Malaria Aviar/transmisión , Plasmodium/patogenicidad , Animales , Brasil , Malaria Aviar/parasitología , Plasmodium/genética , Reacción en Cadena de la Polimerasa
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