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Andrew M. Ramey - One of the best experts on this subject based on the ideXlab platform.
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Negligible evidence for detrimental effects of Leucocytozoon infections among Emperor Geese (Anser canagicus) breeding on the Yukon-Kuskokwim Delta, Alaska
'Elsevier BV', 2021Co-Authors: Andrew M. Ramey, Ananias A. Escalante, John A Reed, Raymond M. Buchheit, Brian D. Uher-koch, Andreína M. Pacheco, Joel A. SchmutzAbstract:Emperor Geese (Anser canagicus) are iconic waterfowl endemic to Alaska and adjacent areas of northeastern Russia that are considered to be near threatened by the International Union for Conservation. This species has been identified as harboring diverse viruses and parasites which have, at times, been associated with disease in other avian taxa. To better assess if disease represents a vulnerability for Emperor Geese breeding on the Yukon-Kuskokwim Delta, Alaska, we evaluated if haemosporidian parasites were associated with decreased mass or survival among adult female nesting birds captured during 2006–2016. Through molecular analyses, we detected genetically diverse Leucocytozoon, Haemoproteus, and Plasmodium parasites in 28%, 1%, and 1% of 607 blood samples screened in triplicate, respectively. Using regression analysis, we found evidence for a small effect of Leucocytozoon infection on the mass of incubating adult female Emperor Geese. The estimated mass of infected individuals was approximately 43 g (95% CI: 20–67 g), or approximately 2%, less than uninfected birds when captured during the second half of incubation (days 11–25). We did not, however, find support for an effect of Leucocytozoon infection on survival of adult female nesting Emperor Geese using a multi-state hidden Markov framework to analyze mark-resight and recapture data. Using parasite mitochondrial DNA cytochrome b sequences, we identified 23 haplotypes among infected Emperor Geese. Leucocytozoon haplotypes clustered into three phylogenetically supported clades designated as ‘L. simondi clade A’, ‘L. simondi clade B’, and ‘other Leucocytozoon’. We did not find evidence that parasites assigned to any of these clades were associated with differential mass measures among nesting adult female Emperor Geese. Collectively, our results provide negligible evidence for Leucocytozoon parasites as causing detrimental effects to adult female Emperor Geese breeding on the Yukon-Kuskokwim Delta
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evidence for haemosporidian parasite infections in spectacled eiders somateria fischeri sampled in alaska usa during the breeding season
Journal of Wildlife Diseases, 2018Co-Authors: John A Reed, Joel A. Schmutz, Matthew M. Smith, Matthew G Sexson, Andrew M. RameyAbstract:Abstract We assessed hematozoa infection in Spectacled Eiders (Somateria fischeri) at two areas in Alaska. No Haemoproteus or Plasmodium species were detected. Leucocytozoon prevalence was 6.5% for adults across sites and 41.9% for juveniles sampled in the Arctic, providing evidence for local transmission. All Leucocytozoon haplotypes were previously detected in waterfowl.
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prevalence and genetic diversity of haematozoa in south american waterfowl and evidence for intercontinental redistribution of parasites by migratory birds
International journal for parasitology. Parasites and wildlife, 2015Co-Authors: Matthew M. Smith, Andrew M. RameyAbstract:To understand the role of migratory birds in the movement and transmission of haematozoa within and between continental regions, we examined 804 blood samples collected from eleven endemic species of South American waterfowl in Peru and Argentina for infection by Haemoproteus, Plasmodium, and/or Leucocytozoon blood parasites. Infections were detected in 25 individuals of six species for an overall apparent prevalence rate of 3.1%. Analysis of haematozoa mitochondrial DNA revealed twelve distinct parasite haplotypes infecting South American waterfowl, four of which were identical to lineages previously observed infecting ducks and swans sampled in North America. Analysis of parasite mitochondrial DNA sequences revealed close phylogenetic relationships between lineages originating from waterfowl samples regardless of continental affiliation. In contrast, more distant phylogenetic relationships were observed between parasite lineages from waterfowl and passerines sampled in South America for Haemoproteus and Leucocytozoon, suggesting some level of host specificity for parasites of these genera. The detection of identical parasite lineages in endemic, South American waterfowl and North American ducks and swans, paired with the close phylogenetic relationships of haematozoa infecting waterfowl on both continents, provides evidence for parasite redistribution between these regions by migratory birds.
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evidence for intercontinental parasite exchange through molecular detection and characterization of haematozoa in northern pintails anas acuta sampled throughout the north pacific basin
International journal for parasitology. Parasites and wildlife, 2015Co-Authors: Andrew M. Ramey, Joseph P. Fleskes, Joel A. Schmutz, John A Reed, Go Fujita, Bradley D Scotton, Bruce Casler, Kan Konishi, Kiyoshi UchidaAbstract:Empirical evidence supports wild birds as playing a role in the interhemispheric exchange of bacteria and viruses; however, data supporting the redistribution of parasites among continents are limited. In this study, the hypothesis that migratory birds contribute to the redistribution of parasites between continents was tested by sampling northern pintails (Anas acuta) at locations throughout the North Pacific Basin in North America and East Asia for haemosporidian infections and assessing the genetic evidence for parasite exchange. Of 878 samples collected from birds in Alaska (USA), California (USA), and Hokkaido (Japan) during August 2011–May 2012 and screened for parasitic infections using molecular techniques, Leucocytozoon, Haemoproteus, and Plasmodium parasites were detected in 555 (63%), 44 (5%), and 52 (6%) samples, respectively. Using an occupancy modeling approach, the probability of detecting parasites via replicate genetic tests was estimated to be high (ρ > 0.95). Multi-model inference supported variation of Leucocytozoon parasite prevalence by northern pintail age class and geographic location of sampling in contrast to Haemoproteus and Plasmodium parasites for which there was only support for variation in parasite prevalence by sampling location. Thirty-one unique mitochondrial DNA haplotypes were detected among haematozoa infecting northern pintails including seven lineages shared between samples from North America and Japan. The finding of identical parasite haplotypes at widely distributed geographic locations and general lack of genetic structuring by continent in phylogenies for Leucocytozoon and Plasmodium provides evidence for intercontinental genetic exchange of haemosporidian parasites. Results suggest that migratory birds, including waterfowl, could therefore facilitate the introduction of avian malaria and other haemosporidia to novel hosts and spatially distant regions.
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Genetic diversity and host specificity varies across three genera of blood parasites in ducks of the Pacific Americas Flyway.
PloS one, 2015Co-Authors: Andrew B. Reeves, Matthew M. Smith, Brandt W. Meixell, Joseph P. Fleskes, Andrew M. RameyAbstract:Birds of the order Anseriformes, commonly referred to as waterfowl, are frequently infected by Haemosporidia of the genera Haemoproteus, Plasmodium, and Leucocytozoon via dipteran vectors. We analyzed nucleotide sequences of the Cytochrome b (Cytb) gene from parasites of these genera detected in six species of ducks from Alaska and California, USA to characterize the genetic diversity of Haemosporidia infecting waterfowl at two ends of the Pacific Americas Flyway. In addition, parasite Cytb sequences were compared to those available on a public database to investigate specificity of genetic lineages to hosts of the order Anseriformes. Haplotype and nucleotide diversity of Haemoproteus Cytb sequences was lower than was detected for Plasmodium and Leucocytozoon parasites. Although waterfowl are presumed to be infected by only a single species of Leucocytozoon, L. simondi, diversity indices were highest for haplotypes from this genus and sequences formed five distinct clades separated by genetic distances of 4.9%–7.6%, suggesting potential cryptic speciation. All Haemoproteus and Leucocytozoon haplotypes derived from waterfowl samples formed monophyletic clades in phylogenetic analyses and were unique to the order Anseriformes with few exceptions. In contrast, waterfowl-origin Plasmodium haplotypes were identical or closely related to lineages found in other avian orders. Our results suggest a more generalist strategy for Plasmodium parasites infecting North American waterfowl as compared to those of the genera Haemoproteus and Leucocytozoon.
Ravinder N. M. Sehgal - One of the best experts on this subject based on the ideXlab platform.
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Detection and prevalence of Haemoproteus archilochus (Haemosporida, Haemoproteidae) in two species of California hummingbirds
Parasitology research, 2017Co-Authors: A. C. Bradshaw, Jenny S. Carlson, Lisa A. Tell, Holly B. Ernest, S. Bahan, Ravinder N. M. SehgalAbstract:Haemosporidian blood parasites are transmitted to a wide range of avian hosts via blood-sucking dipteran vectors. Microscopy has revealed an impressive diversity of avian haemosporidia with more than 250 species described. Moreover, PCR and subsequent sequence analyses have suggested a much greater diversity of haemosporidia than morphological analyses alone. Given the importance of these parasites, very few studies have focused on the charismatic hummingbirds. To date, three Haemoproteus species (Haemoproteus archilochus, Haemoproteus trochili, and Haemoproteus witti) and one Leucocytozoon species (Leucocytozoon quynzae) have been described in blood samples taken from hummingbirds (Trochilidae). Unconfirmed Plasmodium lineages have also been detected in hummingbirds. Here, we report the detection of H. archilochus in two hummingbird species (Calypte anna and Archilochus alexandri) sampled in Northern California and perform a phylogenetic analysis of mitochondrial cytochrome b (cyt b) gene lineages. A total of 261 hummingbirds (157 C. anna, 104 A. alexandri) were sampled and screened for blood parasites using PCR and microscopy techniques. Combining both methods, 4 (2.55%) haemosporidian infections were detected in C. anna and 18 (17.31%) haemosporidian infections were detected in A. alexandri. Molecular analyses revealed four distinct H. archilocus cyt b lineages, which clustered as a monophyletic clade. No species of Plasmodium or Leucocytozoon were detected in this study, raising the possibility of specific vector associations with hummingbirds. These results provide resources for future studies of haemosporidian prevalence, diversity, and pathogenicity in California hummingbird populations.
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Description and molecular characterization of a new Leucocytozoon parasite (Haemosporida: Leucocytozoidae), Leucocytozoon californicus sp. nov., found in American kestrels (Falco sparverius sparverius)
Parasitology Research, 2016Co-Authors: Erika Walther, Gediminas Valkiūnas, Tatjana A. Iezhova, Elizabeth A. Wommack, Rauri C. K. Bowie, Ravinder N. M. SehgalAbstract:Diurnal raptors in the order Accipitriformes are commonly parasitized with Leucocytozoon spp., and the prevalence and intensity of parasitemia are often high. However, for raptors in Falconiformes, several studies have reported relatively low prevalences (1 % or less) of Leucocytozoon spp. Leucocytozoon parasite pathogenicity has been documented in falcons, but little is known about the diversity, prevalence, and phylogenetic relationships among Leucocytozoon species in these predatory birds. The research reported here combines molecular and microscopic techniques to identify and describe Leucocytozoon parasites in Falco sparverius sparverius , the American kestrel, and place those parasites into a phylogenetic context with leucocytozoids previously found in other diurnal raptors (Accipitriformes), owls (Strigiformes), passerines (Passeriformes), and other bird species. Of 35 American kestrels sampled, 13 birds (37.1 %) were found by PCR to harbor the DNA lineage of a novel species, Leucocytozoon californicus . No other Leucocytozoon parasite lineages were identified in our sample. Phylogenetic analysis revealed that this parasite clusters more closely with leucocytozoids found in owls and passerines than it does with leucocytozoids found in birds of the genera Buteo and Accipiter of the order Accipitriformes. This is the first described species of Leucocytozoon that parasitizes diurnal raptors in which gametocytes develop exclusively in roundish host blood cells. It is also the first Leucocytozoon species that is described and named in birds of the Falconiformes, in which, for unclear reasons, leucocytozoids are significantly less prevalent and less diverse than in raptors with a similar behavioral ecology belonging to the Accipitriformes.
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distribution diversity and drivers of blood borne parasite co infections in alaskan bird populations
International Journal for Parasitology, 2014Co-Authors: Khouanchy S Oakgrove, Ryan J Harrigan, Claire Loiseau, Sue L Guers, Bruce Seppi, Ravinder N. M. SehgalAbstract:Avian species are commonly infected by multiple parasites, however few studies have investigated the environmental determinants of the prevalence of co-infection over a large scale. Here we believe that we report the first, detailed ecological study of the prevalence, diversity and co-infections of four avian blood-borne parasite genera: Plasmodium spp., Haemoproteus spp., Leucocytozoon spp. and Trypanosoma spp. We collected blood samples from 47 resident and migratory bird species across a latitudinal gradient in Alaska. From the patterns observed at collection sites, random forest models were used to provide evidence of associations between bioclimatic conditions and the prevalence of parasite co-infection distribution. Molecular screening revealed a higher prevalence of haematozoa (53%) in Alaska than previously reported. Leucocytozoons had the highest diversity, prevalence and prevalence of co-infection. Leucocytozoon prevalence (35%) positively correlated with Trypanosoma prevalence (11%), negatively correlated with Haemoproteus prevalence (14%) and had no correlation with Plasmodium prevalence (7%). We found temperature, precipitation and tree cover to be the primary environmental drivers that show a relationship with the prevalence of co-infection. The results provide insight into the impacts of bioclimatic drivers on parasite ecology and intra-host interactions, and have implications for the study of infectious diseases in rapidly changing environments.
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north american transmission of hemosporidian parasites in the swainson s thrush catharus ustulatus a migratory songbird
Journal of Parasitology, 2013Co-Authors: Molly Dodge, Susan L Guers, Cagan H Sekercioglu, Ravinder N. M. SehgalAbstract:The geographic structuring of parasite communities across the range of a single host species can illuminate patterns of host-population connectivity. To determine the location of parasite transmission in a Neotropical migrant bird species, we sampled adult and hatch-year (HY) birds across the breeding and wintering range of the Swainson's thrush (SWTH), an abundant passerine with a migratory divide. We examined the phylogenetic relationships among cytochrome b lineages of the avian blood parasite genera Haemoproteus, Plasmodium, and Leucocytozoon and determined the transmission location of unique lineages. We found that Haemoproteus and Plasmodium lineages are transmitted on California breeding grounds, whereas Leucocytozoon transmission occurs on Alaskan breeding grounds. The presence of hemosporidians on wintering grounds and shared lineages between the SWTH and resident species suggests that transmission of some of these lineages occurs on both breeding and wintering grounds. We emphasize that the sampling of HY birds and local resident heterospecifics will supplement vector studies to determine the key players in hemosporidian host switching and range-expansion events.
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nested cytochrome b polymerase chain reaction diagnostics detect sporozoites of hemosporidian parasites in peripheral blood of naturally infected birds
Journal of Parasitology, 2009Co-Authors: Gediminas Valkiūnas, Tatjana A. Iezhova, Claire Loiseau, Ravinder N. M. SehgalAbstract:Some discrepancies between microscopy and PCR-based methods have been recently recorded in the diagnosis of Leucocytozoon spp. infection in naturally infected birds. To clarify this issue, blood samples from 109 yellow-whiskered greenbuls Andropadus latirostris were investigated using both the microscopic examination of blood films and a nested mitochondrial cytochrome b PCR. The overall prevalence of Leucocytozoon spp. infection was 4% after the standard microscopic examination and 17% using the PCR diagnostics. Samples from 9 randomly chosen birds that were microscopy negative, but PCR positive, were then examined microscopically by screening 2 entire blood films from each individual bird. Sporozoites of Leucocytozoon spp. were observed in 4 birds, and 1 gametocyte of the parasite was seen in each of 2 birds. We conclude that sensitive PCR-based diagnostics are able to detect extremely light parasitemias of circulating sporozoites and gametocytes of hemosporidian parasites. Because of the PCR detection of sporozoites of unknown fate in the peripheral circulation, conclusions regarding the distribution of hemosporidian lineages in wildlife should be made with caution. To be accepted as the lineages of successfully developing species of hemosporidians, such PCR-based information should be supported with the detection of blood stages of the parasites. The present study emphasizes the crucial need for a synthesis of information provided by the tools of traditional parasitology and molecular biology, particularly in field studies of blood parasites.
Gediminas Valkiūnas - One of the best experts on this subject based on the ideXlab platform.
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The buffy coat method: a tool for detection of blood parasites without staining procedures.
Parasites & vectors, 2020Co-Authors: Carolina R. F. Chagas, Rasa Binkienė, Mikas Ilgūnas, Tatjana Iezhova, Gediminas ValkiūnasAbstract:Blood parasites belonging to the Apicomplexa, Trypanosomatidae and Filarioidea are widespread in birds and have been studied extensively. Microscopical examination (ME) of stained blood films remains the gold standard method for the detection of these infections in birds, particularly because co-infections predominate in wildlife. None of the available molecular tools can detect all co-infections at the same time, but ME provides opportunities for this to be achieved. However, fixation, drying and staining of blood films as well as their ME are relatively time-consuming. This limits the detection of infected hosts during fieldwork when captured animals should be released soon after sampling. It is an obstacle for quick selection of donor hosts for parasite experimental, histological and other investigations in the field. This study modified, tested and described the buffy coat method (BCM) for quick diagnostics (~ 20 min/sample) of avian blood parasites. Blood of 345 birds belonging to 42 species was collected, and each sample was examined using ME of stained blood films and the buffy coat, which was examined after centrifugation in capillary tubes and after being transferred to objective glass slides. Parasite detection using these methods was compared using sensitivity, specificity, positive and negative predictive values and Cohen’s kappa index. Haemoproteus, Leucocytozoon, Plasmodium, microfilariae, Trypanosoma and Lankesterella parasites were detected. BCM had a high sensitivity (> 90%) and specificity (> 90%) for detection of Haemoproteus and microfilariae infections. It was of moderate sensitivity (57%) and high specificity (> 90%) for Lankesterella infections, but of low sensitivity (20%) and high specificity (> 90%) for Leucocytozoon infections. Trypanosoma and Plasmodium parasites were detected only by BCM and ME, respectively. According to Cohen’s kappa index, the agreement between two diagnostic tools was substantial for Haemoproteus (0.80), moderate for Lankesterella (0.46) and fair for microfilariae and Leucocytozoon (0.28) infections. BCM is sensitive and recommended as a quick and reliable tool to detect Haemoproteus, Trypanosoma and microfilariae parasites during fieldwork. However, it is not suitable for detection of species of Leucocytozoon and Plasmodium. BCM is a useful tool for diagnostics of blood parasite co-infections. Its application might be extended to studies of blood parasites in other vertebrates during field studies.
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molecular probes for the identification of avian haemoproteus and Leucocytozoon parasites in tissue sections by chromogenic in situ hybridization
Parasites & Vectors, 2019Co-Authors: Tanja Himmel, Mikas Ilgūnas, Gediminas Valkiūnas, Josef Harl, Anna Kubberheiss, Cornelia Konicek, Nuhacet Fernandez, Carles Juansalles, Herbert WeissenbockAbstract:Background Avian haemosporidian parasites can cause severe disease in their hosts due to excessive exo-erythrocytic merogony and anaemia caused by blood stages. Notably, the development of megalomeronts by species of Haemoproteus and Leucocytozoon has been associated with mortalities in birds. Diagnosis of lethal infections is currently accomplished by the detection of parasites’ tissue stages in histological sections combined with PCR and sequencing. However, sequences frequently are not reliably obtained and the generic discrimination of exo-erythrocytic tissue stages based on morphological characters is challenging. Therefore, the present study aimed at developing specific molecular probes for the identification of Haemoproteus spp. and Leucocytozoon spp. in histological sections using chromogenic in situ hybridization.
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Malaria parasites and related haemosporidians cause mortality in cranes: a study on the parasites diversity, prevalence and distribution in Beijing Zoo
'Springer Science and Business Media LLC', 2018Co-Authors: Ting Jia, Gediminas Valkiūnas, Xi Huang, Minghai Yang, Changming Zheng, Yanyun Zhang, Lu Dong, Xun Suo, Chenglin ZhangAbstract:Abstract Background Malaria parasites and related haemosporidian parasites are widespread and may cause severe diseases in birds. These pathogens should be considered in projects aiming breeding of birds for purposes of sustained ex situ conservation. Cranes are the ‘flagship species’ for health assessment of wetland ecosystems, and the majority of species are endangered. Malaria parasites and other haemosporidians have been reported in cranes, but the host-parasite relationships remain insufficiently understood. Morbidity of cranes due to malaria has been reported in Beijing Zoo. This study report prevalence, diversity and distribution of malaria parasites and related haemosporidians in cranes in Beijing Zoo and suggest simple measures to protect vulnerable individuals. Methods In all, 123 cranes (62 adults and 61 juveniles) belonging to 10 species were examined using PCR-based testing and microscopic examination of blood samples collected in 2007–2014. All birds were maintained in open-air aviaries, except for 19 chicks that were raised in a greenhouse with the aim to protect them from bites of blood-sucking insects. Bayesian phylogenetic analysis was used to identify the closely related avian haemosporidian parasites. Results Species of Plasmodium (5 lineages), Haemoproteus (1) and Leucocytozoon (2) were reported. Malaria parasites predominated (83% of all reported infections). The overall prevalence of haemosporidians in juveniles was approximately seven-fold higher than in adults, indicating high susceptibility of chicks and local transmission. Juvenile and adult birds hosted different lineages of Plasmodium, indicating that chicks got infection from non-parent birds. Plasmodium relictum (pSGS1) was the most prevalent malaria parasite. Mortality was not reported in adults, but 53% of infected chicks died, with reports of co-infection with Plasmodium and Leucocytozoon species. All chicks maintained in the greenhouse were non-infected and survived. Species of Leucocytozoon were undetectable by commonly used PCR protocol, but readily visible in blood films. Conclusion Crane chicks often die due to malaria and Leucocytozoon infections, which they likely gain from wild free-living birds in Beijing Zoo. Molecular diagnostics of crane Leucocytozoon parasites needs improvement. Because the reported infections are mainly chick diseases, the authors recommend maintaining of juvenile birds in vector-free facilities until the age of approximately 6 months before they are placed in open-air aviaries
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Description and molecular characterization of a new Leucocytozoon parasite (Haemosporida: Leucocytozoidae), Leucocytozoon californicus sp. nov., found in American kestrels (Falco sparverius sparverius)
Parasitology Research, 2016Co-Authors: Erika Walther, Gediminas Valkiūnas, Tatjana A. Iezhova, Elizabeth A. Wommack, Rauri C. K. Bowie, Ravinder N. M. SehgalAbstract:Diurnal raptors in the order Accipitriformes are commonly parasitized with Leucocytozoon spp., and the prevalence and intensity of parasitemia are often high. However, for raptors in Falconiformes, several studies have reported relatively low prevalences (1 % or less) of Leucocytozoon spp. Leucocytozoon parasite pathogenicity has been documented in falcons, but little is known about the diversity, prevalence, and phylogenetic relationships among Leucocytozoon species in these predatory birds. The research reported here combines molecular and microscopic techniques to identify and describe Leucocytozoon parasites in Falco sparverius sparverius , the American kestrel, and place those parasites into a phylogenetic context with leucocytozoids previously found in other diurnal raptors (Accipitriformes), owls (Strigiformes), passerines (Passeriformes), and other bird species. Of 35 American kestrels sampled, 13 birds (37.1 %) were found by PCR to harbor the DNA lineage of a novel species, Leucocytozoon californicus . No other Leucocytozoon parasite lineages were identified in our sample. Phylogenetic analysis revealed that this parasite clusters more closely with leucocytozoids found in owls and passerines than it does with leucocytozoids found in birds of the genera Buteo and Accipiter of the order Accipitriformes. This is the first described species of Leucocytozoon that parasitizes diurnal raptors in which gametocytes develop exclusively in roundish host blood cells. It is also the first Leucocytozoon species that is described and named in birds of the Falconiformes, in which, for unclear reasons, leucocytozoids are significantly less prevalent and less diverse than in raptors with a similar behavioral ecology belonging to the Accipitriformes.
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Description of Leucocytozoon quynzae sp. nov. (Haemosporida, Leucocytozoidae) from hummingbirds, with remarks on distribution and possible vectors of leucocytozoids in South America
Parasitology Research, 2014Co-Authors: Nubia E. Matta, Gediminas Valkiūnas, Ingrid A. Lotta, Angie D. González, M. Andreína Pacheco, Ananias A. Escalante, Ligia I. Moncada, Oscar A. Rodríguez-fandiñoAbstract: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.
Joseph P. Fleskes - One of the best experts on this subject based on the ideXlab platform.
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evidence for intercontinental parasite exchange through molecular detection and characterization of haematozoa in northern pintails anas acuta sampled throughout the north pacific basin
International journal for parasitology. Parasites and wildlife, 2015Co-Authors: Andrew M. Ramey, Joseph P. Fleskes, Joel A. Schmutz, John A Reed, Go Fujita, Bradley D Scotton, Bruce Casler, Kan Konishi, Kiyoshi UchidaAbstract:Empirical evidence supports wild birds as playing a role in the interhemispheric exchange of bacteria and viruses; however, data supporting the redistribution of parasites among continents are limited. In this study, the hypothesis that migratory birds contribute to the redistribution of parasites between continents was tested by sampling northern pintails (Anas acuta) at locations throughout the North Pacific Basin in North America and East Asia for haemosporidian infections and assessing the genetic evidence for parasite exchange. Of 878 samples collected from birds in Alaska (USA), California (USA), and Hokkaido (Japan) during August 2011–May 2012 and screened for parasitic infections using molecular techniques, Leucocytozoon, Haemoproteus, and Plasmodium parasites were detected in 555 (63%), 44 (5%), and 52 (6%) samples, respectively. Using an occupancy modeling approach, the probability of detecting parasites via replicate genetic tests was estimated to be high (ρ > 0.95). Multi-model inference supported variation of Leucocytozoon parasite prevalence by northern pintail age class and geographic location of sampling in contrast to Haemoproteus and Plasmodium parasites for which there was only support for variation in parasite prevalence by sampling location. Thirty-one unique mitochondrial DNA haplotypes were detected among haematozoa infecting northern pintails including seven lineages shared between samples from North America and Japan. The finding of identical parasite haplotypes at widely distributed geographic locations and general lack of genetic structuring by continent in phylogenies for Leucocytozoon and Plasmodium provides evidence for intercontinental genetic exchange of haemosporidian parasites. Results suggest that migratory birds, including waterfowl, could therefore facilitate the introduction of avian malaria and other haemosporidia to novel hosts and spatially distant regions.
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Genetic diversity and host specificity varies across three genera of blood parasites in ducks of the Pacific Americas Flyway.
PloS one, 2015Co-Authors: Andrew B. Reeves, Matthew M. Smith, Brandt W. Meixell, Joseph P. Fleskes, Andrew M. RameyAbstract:Birds of the order Anseriformes, commonly referred to as waterfowl, are frequently infected by Haemosporidia of the genera Haemoproteus, Plasmodium, and Leucocytozoon via dipteran vectors. We analyzed nucleotide sequences of the Cytochrome b (Cytb) gene from parasites of these genera detected in six species of ducks from Alaska and California, USA to characterize the genetic diversity of Haemosporidia infecting waterfowl at two ends of the Pacific Americas Flyway. In addition, parasite Cytb sequences were compared to those available on a public database to investigate specificity of genetic lineages to hosts of the order Anseriformes. Haplotype and nucleotide diversity of Haemoproteus Cytb sequences was lower than was detected for Plasmodium and Leucocytozoon parasites. Although waterfowl are presumed to be infected by only a single species of Leucocytozoon, L. simondi, diversity indices were highest for haplotypes from this genus and sequences formed five distinct clades separated by genetic distances of 4.9%–7.6%, suggesting potential cryptic speciation. All Haemoproteus and Leucocytozoon haplotypes derived from waterfowl samples formed monophyletic clades in phylogenetic analyses and were unique to the order Anseriformes with few exceptions. In contrast, waterfowl-origin Plasmodium haplotypes were identical or closely related to lineages found in other avian orders. Our results suggest a more generalist strategy for Plasmodium parasites infecting North American waterfowl as compared to those of the genera Haemoproteus and Leucocytozoon.
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evaluation of blood and muscle tissues for molecular detection and characterization of hematozoa infections in northern pintails anas acuta wintering in california
International journal for parasitology. Parasites and wildlife, 2013Co-Authors: Andrew M. Ramey, Joseph P. Fleskes, Joel A. Schmutz, Michael J YabsleyAbstract:Information on the molecular detection of hematozoa from different tissue types and multiple years would be useful to inform sample collection efforts and interpret results of meta-analyses or investigations spanning multiple seasons. In this study, we tested blood and muscle tissue collected from northern pintails (Anas acuta) during autumn and winter of different years to evaluate prevalence and genetic diversity of Leucocytozoon, Haemoproteus, and Plasmodium infections in this abundant waterfowl species of the Central Valley of California. We first compared results for paired blood and wing muscle samples to assess the utility of different tissue types for molecular investigations of haemosporidian parasites. Second, we explored inter-annual variability of hematozoa infection in Central Valley northern pintails and investigated possible effects of age, sex, and sub-region of sample collection on estimated parasite detection probability and prevalence. We found limited evidence for differences between tissue types in detection probability and prevalence of Leucocytozoon, Haemoproteus, and Plasmodium parasites, which supports the utility of both sample types for obtaining information on hematozoan infections. However, we detected 11 haemosporidian mtDNA cyt b haplotypes in blood samples vs. six in wing muscle tissue collected during the same sample year suggesting an advantage to using blood samples for investigations of genetic diversity. Estimated prevalence of Leucocytozoon parasites was greater during 2006–2007 as compared to 2011–2012 and four unique haemosporidian mtDNA cyt b haplotypes were detected in the former sample year but not in the latter. Seven of 15 mtDNA cyt b haplotypes detected in northern pintails had 100% identity with previously reported hematozoa lineages detected in waterfowl (Haemoproteus and Leucocytozoon) or other avian taxa (Plasmodium) providing support for lack of host specificity for some parasite lineages.
Susan L. Perkins - One of the best experts on this subject based on the ideXlab platform.
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Integrating coalescent species delimitation with analysis of host specificity reveals extensive cryptic diversity despite minimal mitochondrial divergence in the malaria parasite genus Leucocytozoon
BMC Evolutionary Biology, 2018Co-Authors: Spencer Galen, Renato Nunes, Paul R. Sweet, Susan L. PerkinsAbstract:Background Coalescent methods that use multi-locus sequence data are powerful tools for identifying putatively reproductively isolated lineages, though this approach has rarely been used for the study of microbial groups that are likely to harbor many unrecognized species. Among microbial symbionts, integrating genetic species delimitation methods with trait data that could indicate reproductive isolation, such as host specificity data, has rarely been used despite its potential to inform species limits. Here we test the ability of an integrative approach combining genetic and host specificity data to delimit species within the avian malaria parasite genus Leucocytozoon in central Alaska. Results We sequenced seven nuclear loci for 69 Leucocytozoon samples and used multiple species delimitation methods (GMYC and BPP models), tested for differences in host infection patterns among putative species based on 406 individual infections, and characterized parasite morphology. We found that cryptic morphology has masked a highly diverse Leucocytozoon assemblage, with most species delimitation methods recovering support for at least 21 separate species that occur sympatrically and have divergent host infection patterns. Reproductive isolation among putative species appears to have evolved despite low mtDNA divergence, and in one instance two Leucocytozoon cytb haplotypes that differed by a single base pair (~ 0.2% divergence) were supported as separate species. However, there was no consistent association between mtDNA divergence and species limits. Among cytb haplotypes that differed by one to three base pairs we observed idiosyncratic patterns of nuclear and ecological divergence, with cytb haplotype pairs found to be either conspecific, reproductively isolated with no divergence in host specificity, or reproductively isolated with divergent patterns of host specialization. Conclusion Integrating multi-locus genetic species delimitation methods and non-traditional ecological data types such as host specificity provide a novel view of the diversity of avian malaria parasites that has been missed previously using morphology and mtDNA barcodes. Species delimitation methods show that Leucocytozoon is highly species-rich in Alaska, and the genus is likely to harbor extraordinary species-level diversity worldwide. Integrating genetic and ecological data will be an important approach for understanding the diversity and evolutionary history of microbial symbionts moving forward.
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a molecular phylogeny of malarial parasites recovered from cytochrome b gene sequences
Journal of Parasitology, 2002Co-Authors: Susan L. Perkins, Jos J SchallAbstract:A phylogeny of haemosporidian parasites (phylum Apicomplexa, family Plasmodiidae) was recovered using mitochondrial cytochrome b gene sequences from 52 species in 4 genera (Plasmodium, Hepatocystis, Haemoproteus, and Leucocytozoon), including parasite species infecting mammals, birds, and reptiles from over a wide geographic range. Leucocytozoon species emerged as an appropriate out-group for the other malarial parasites. Both parsimony and maximum-likelihood analyses produced similar phylogenetic trees. Life-history traits and parasite morphology, traditionally used as taxonomic characters, are largely phylogenetically uninformative. The Plasmodium and Hepatocystis species of mammalian hosts form 1 well-supported clade, and the Plasmodium and Haemoproteus species of birds and lizards form a second. Within this second clade, the relationships between taxa are more complex. Although jackknife support is weak, the Plasmodium of birds may form 1 clade and the Haemoproteus of birds another clade, but the para...