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1.
Am Nat ; 201(4): 603-609, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958002

RESUMO

AbstractAnimals have evolved a variety of adaptations to care for their body surfaces, such as grooming behavior, which keeps the integument clean, parasite-free, and properly arranged. Despite extensive research on the grooming of mammals, birds, and arthropods, the survival value of grooming has never been directly measured in natural populations. We monitored grooming and survival in a population of marked American kestrels (Falco sparverius) on San Salvador Island, Bahamas. We found a strong association between time spent grooming and survival over a 2-year period. The quadratic relationship we show is consistent with stabilizing natural selection on grooming time. To our knowledge, this is the first evidence for a correlation between grooming time and survival in a natural population. Grooming time may predict the survival of many animal taxa, but additional studies are needed to determine the shape and strength of the relationship among birds, mammals, and arthropods.


Assuntos
Artrópodes , Falconiformes , Animais , Asseio Animal , Aves , Bahamas , Mamíferos
2.
J Anim Ecol ; 92(10): 1992-2004, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37583129

RESUMO

Co-parasitism is ubiquitous and has important consequences for the ecology and evolution of wild host populations. Studies of parasite co-infections remain limited in scope, with few experimental tests of the fitness consequences of multiple parasites, especially in natural populations. We measured the separate and combined effects of Philornis seguyi nest flies and shiny cowbirds Molothrus bonariensis on the fitness of a shared host, the chalk-browed mockingbird (Mimus saturninus) in Argentina. Using a two-factor experimental approach, we manipulated the presence of nest flies and cowbirds in mockingbird nests and assessed their effects on mockingbird haemoglobin levels, begging and provisioning rates, body size, and fledging success. We also monitored rates of nest predation in relation to parasitism by flies and cowbirds. Nest flies reduced the haemoglobin concentration, body size, and fledging success of mockingbirds, likely because mockingbirds did not compensate for parasitism by begging more or feeding their nestlings more. Cowbirds also reduced the fledging success of mockingbirds, even though they had no detectable effect on haemoglobin or body size. Nests with cowbirds, which beg more than mockingbirds, attracted more nest predators. There was no significant interaction between the effects of flies and cowbirds on any component of mockingbird fitness. The combined effects of nest flies and cowbirds were strictly additive. In summary, we show that nest flies and cowbirds both reduce host fitness, but do not have interactive effects in co-parasitized nests. Our results further suggest that predators exacerbate the effects of nest flies and cowbirds on their hosts. Our study shows that the fitness consequences of co-parasitism are complex, especially in the context of community-level interactions.


El co-parasitismo es ubicuo y tiene consecuencias importantes para la ecología y la evolución de las poblaciones de hospedadores silvestres. Los estudios de coinfecciones por parásitos poseen un alcance limitado, con pocos trabajos experimentales que analicen las consecuencias del parasitismo múltiple sobre la eficacia biológica, especialmente en poblaciones naturales. Medimos los efectos separados y combinados de las moscas de los nidos Philornis seguyi y el tordo renegrido (Molothrus bonariensis) sobre la eficacia biológica de un hospedador compartido, la calandria grande (Mimus saturninus) en Argentina. Utilizando un enfoque experimental de dos factores, manipulamos la presencia de moscas de nido y tordos en los nidos de calandrias y evaluamos sus efectos sobre los niveles de hemoglobina, las tasas de solicitud de alimento y aprovisionamiento, el tamaño corporal y el éxito de supervivencia de los pichones de calandria. También monitoreamos las tasas de depredación de nidos en relación con el parasitismo de moscas y tordos. Las moscas de los nidos redujeron la concentración de hemoglobina, el tamaño corporal y el éxito de supervivencia de los pichones de calandrias, probablemente porque las calandrias no compensaron el parasitismo solicitando más alimento o alimentando más a sus pichones. Los tordos también redujeron el éxito de supervivencia de las calandrias, aunque no tuvieron un efecto detectable sobre la hemoglobina o el tamaño corporal. Los nidos con tordos, quienes solicitaron más alimento más que las calandrias, atrajeron a más depredadores de nidos. El aumento de la depredación de nidos asociado a la alta intensidad de solicitud de alimento puede explicar por qué las calandrias en Argentina no solicitan más alimento en respuesta al parasitismo de las moscas. No hubo una interacción significativa entre los efectos de las moscas y los tordos en ningún componente de la eficacia biológica de las calandrias. Los efectos combinados de las moscas de los nidos y los tordos fueron estrictamente aditivos. En resumen, mostramos que las moscas de los nidos y los tordos reducen la eficacia biológica del hospedador, pero no tienen efectos interactivos en los nidos co-parasitados. Nuestros resultados sugieren además que los depredadores exacerban los efectos de las moscas de los nidos y los tordos sobre sus hospedadores. Nuestro estudio muestra que las consecuencias del co-parasitismo sobre la eficacia biológica son complejas, especialmente en el contexto de las interacciones a nivel comunitario.

3.
Proc Biol Sci ; 289(1970): 20220042, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35259992

RESUMO

Adaptive radiation is an important mechanism of organismal diversification and can be triggered by new ecological opportunities. Although poorly studied in this regard, parasites are an ideal group in which to study adaptive radiations because of their close associations with host species. Both experimental and comparative studies suggest that the ectoparasitic wing lice of pigeons and doves have adaptively radiated, leading to differences in body size and overall coloration. Here, we show that long-distance dispersal by dove hosts was central to parasite diversification because it provided new ecological opportunities for parasites to speciate after host-switching. We further show that among extant parasite lineages host-switching decreased over time, with cospeciation becoming the more dominant mode of parasite speciation. Taken together, our results suggest that host dispersal, followed by host-switching, provided novel ecological opportunities that facilitated adaptive radiation by parasites.


Assuntos
Parasitos , Ftirápteros , Animais , Columbidae , Interações Hospedeiro-Parasita , Filogenia
4.
Proc Natl Acad Sci U S A ; 116(27): 13440-13445, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31182608

RESUMO

Ecological speciation occurs when local adaptation generates reproductive isolation as a by-product of natural selection. Although ecological speciation is a fundamental source of diversification, the mechanistic link between natural selection and reproductive isolation remains poorly understood, especially in natural populations. Here, we show that experimental evolution of parasite body size over 4 y (approximately 60 generations) leads to reproductive isolation in natural populations of feather lice on birds. When lice are transferred to pigeons of different sizes, they rapidly evolve differences in body size that are correlated with host size. These differences in size trigger mechanical mating isolation between lice that are locally adapted to the different sized hosts. Size differences among lice also influence the outcome of competition between males for access to females. Thus, body size directly mediates reproductive isolation through its influence on both intersexual compatibility and intrasexual competition. Our results confirm that divergent natural selection acting on a single phenotypic trait can cause reproductive isolation to emerge from a single natural population in real time.


Assuntos
Evolução Biológica , Isolamento Reprodutivo , Adaptação Fisiológica , Animais , Tamanho Corporal , Columbidae/parasitologia , Feminino , Especiação Genética , Interações Hospedeiro-Parasita , Masculino , Ftirápteros/fisiologia , Reprodução , Caracteres Sexuais
5.
Proc Biol Sci ; 286(1897): 20190049, 2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30963843

RESUMO

When confronted with a parasite or pathogen, hosts can defend themselves by resisting or tolerating the attack. While resistance can be diminished when resources are limited, it is unclear how robust tolerance is to changes in environmental conditions. Here, we investigate the sensitivity of tolerance in a single host population living in a highly variable environment. We manipulated the abundance of an invasive parasitic fly, Philornis downsi, in nests of Galápagos mockingbirds ( Mimus parvulus) over four field seasons and measured host fitness in response to parasitism. Mockingbird tolerance to P. downsi varied significantly among years and decreased when rainfall was limited. Video observations indicate that parental provisioning of nestlings appears key to tolerance: in drought years, mockingbirds likely do not have sufficient resources to compensate for the effects of P. downsi. These results indicate that host tolerance is a labile trait and suggest that environmental variation plays a major role in mediating the consequences of host-parasite interactions.


Assuntos
Interações Hospedeiro-Parasita , Espécies Introduzidas , Muscidae/fisiologia , Aves Canoras/fisiologia , Aves Canoras/parasitologia , Animais , Meio Ambiente , Aptidão Genética , Chuva , Estações do Ano , Aves Canoras/genética
6.
Mol Ecol ; 27(12): 2770-2779, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29752753

RESUMO

Dispersal is a fundamental component of the life history of most species. Dispersal influences fitness, population dynamics, gene flow, genetic drift and population genetic structure. Even small differences in dispersal can alter ecological interactions and trigger an evolutionary cascade. Linking such ecological processes with evolutionary patterns is difficult, but can be carried out in the proper comparative context. Here, we investigate how differences in phoretic dispersal influence the population genetic structure of two different parasites of the same host species. We focus on two species of host-specific feather lice (Phthiraptera: Ischnocera) that co-occur on feral rock pigeons (Columba livia). Although these lice are ecologically very similar, "wing lice" (Columbicola columbae) disperse phoretically by "hitchhiking" on pigeon flies (Diptera: Hippoboscidae), while "body lice" (Campanulotes compar) do not. Differences in the phoretic dispersal of these species are thought to underlie observed differences in host specificity, as well as the degree of host-parasite cospeciation. These ecological and macroevolutionary patterns suggest that body lice should exhibit more genetic differentiation than wing lice. We tested this prediction among lice on individual birds and among lice on birds from three pigeon flocks. We found higher levels of genetic differentiation in body lice compared to wing lice at two spatial scales. Our results indicate that differences in phoretic dispersal can explain microevolutionary differences in population genetic structure and are consistent with macroevolutionary differences in the degree of host-parasite cospeciation.


Assuntos
Columbidae/genética , Interações Hospedeiro-Parasita/genética , Parasitos/genética , Ftirápteros/genética , Animais , Evolução Biológica , Doenças das Aves/parasitologia , Dípteros/parasitologia , Ecologia , Genética Populacional/métodos , Especificidade de Hospedeiro , Infestações por Piolhos/parasitologia , Filogenia , Dinâmica Populacional , Especificidade da Espécie
7.
Syst Biol ; 66(6): 896-911, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28108601

RESUMO

Parasitic "wing lice" (Phthiraptera: Columbicola) and their dove and pigeon hosts are a well-recognized model system for coevolutionary studies at the intersection of micro- and macroevolution. Selection on lice in microevolutionary time occurs as pigeons and doves defend themselves against lice by preening. In turn, behavioral and morphological adaptations of the lice improve their ability to evade host defense. Over macroevolutionary time wing lice tend to cospeciate with their hosts; yet, some species of Columbicola have switched to new host species. Understanding the ecological and evolutionary factors that influence coadaptation and codiversification in this system will substantially improve our understanding of coevolution in general. However, further work is hampered by the lack of a robust phylogenetic framework for Columbicola spp. and their hosts. Previous attempts to resolve the phylogeny of Columbicola based on sequences from a few genes provided limited support. Here, we apply a new approach, target restricted assembly, to assemble 977 orthologous gene sequences from whole-genome sequence data generated from very small, ethanol-preserved specimens, representing up to 61 species of wing lice. Both concatenation and coalescent methods were used to estimate the species tree. These two approaches yielded consistent and well-supported trees with 90% of all relationships receiving 100% support, which is a substantial improvement over previous studies. We used this new phylogeny to show that biogeographic ranges are generally conserved within clades of Columbicola wing lice. Limited inconsistencies are probably attributable to intercontinental dispersal of hosts, and host switching by some of the lice. [aTRAM; coalescent; coevolution; concatenation; species tree.].


Assuntos
Genoma/genética , Ftirápteros/classificação , Ftirápteros/genética , Filogenia , Animais , Columbidae/parasitologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Ftirápteros/fisiologia
8.
Mol Phylogenet Evol ; 94(Pt B): 737-751, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26455895

RESUMO

Songbirds host one of the largest, and most poorly understood, groups of lice: the Brueelia-complex. The Brueelia-complex contains nearly one-tenth of all known louse species (Phthiraptera), and the genus Brueelia has over 300 species. To date, revisions have been confounded by extreme morphological variation, convergent evolution, and periodic movement of lice between unrelated hosts. Here we use Bayesian inference based on mitochondrial (COI) and nuclear (EF-1α) gene fragments to analyze the phylogenetic relationships among 333 individuals within the Brueelia-complex. We show that the genus Brueelia, as it is currently recognized, is paraphyletic. Many well-supported and morphologically unified clades within our phylogenetic reconstruction of Brueelia were previously described as genera. These genera should be recognized, and the erection of several new genera should be explored. We show that four distinct ecomorphs have evolved repeatedly within the Brueelia-complex, mirroring the evolutionary history of feather-lice across the entire order. We show that lice in the Brueelia-complex, with some notable exceptions, are extremely host specific and that the host family associations and geographic distributions of these lice are significantly correlated with our understanding of their phylogenetic history. Several ecological phenomena, including phoresis, may be responsible for the macroevolutionary patterns in this diverse group.


Assuntos
Ftirápteros/classificação , Animais , Simulação por Computador , DNA , Plumas/parasitologia , Genes de Insetos , Tipagem Molecular , Filogenia , Alinhamento de Sequência , Aves Canoras/parasitologia
9.
Syst Parasitol ; 90(1): 27-37, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25557745

RESUMO

Our helminthological examination of murid rodents on Luzon Island, Philippines, revealed a remarkable diversity of Hymenolepis Weinland, 1858. Here we describe two new species based on specimens from murid rodents Rattus everetti (Günther) and Apomys datae (Meyer) collected from Luzon Island. Hymenolepis alterna n. sp. differs from all known species of Hymenolepis in having irregularly alternating genital pores. This feature has not been reported from any previously known member of Hymenolepis. Additionally, Hymenolepis alterna n. sp. also differs from other Hymenolepis spp. in the relative position of both poral and antiporal dorsal osmoregulatory canals which are shifted towards the middle of the proglottis in relation to the ventral canals on both sides of the proglottides, and in having curved or twisted external seminal vesicle, covered externally by a dense layer of intensely stained cells. Hymenolepis bilaterala n. sp. differs from all known species of Hymenolepis in the relative position of both poral and antiporal dorsal osmoregulatory canals, which are shifted bilaterally towards the margins of proglottides in relation to the ventral canals, and in possession of testes situated in a triangle and eggs with very thin outer coat. A total of seven species of Hymenolepis are known from the Philippine archipelago. This total includes the cosmopolitan species Hymenolepis diminuta (Rudolphi, 1819), which was likely introduced to the island with invasive rats. Strikingly, all seven known species occur on the island of Luzon alone. By comparison, only six Hymenolepis spp. are known from the whole Palaearctic and seven from the Nearctic despite a much better level of knowledge of rodent helminths in these zoogeographical regions, as well as vast territories, diverse landscapes and very rich rodent fauna. This suggests that Hymenolepis spp. may have undergone an unusually active radiation in the Philippines. Possible explanations of this phenomenon are discussed.


Assuntos
Hymenolepis/anatomia & histologia , Hymenolepis/classificação , Animais , Hymenolepis/isolamento & purificação , Hymenolepis/fisiologia , Filipinas , Roedores/parasitologia , Especificidade da Espécie
10.
Zootaxa ; (3796): 528-44, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24870691

RESUMO

Three new species of the ischnoceran louse genus Emersoniella (Phthiraptera) are described from four species of New Guinean kingfishers and kookaburras (Coraciiformes: Alcedinidae: Halcyoninae). They are: Emersoniella crassicarina n. sp. ex Dacelo gaudichaud Quoy & Gaimard (rufous-bellied kookaburra) and Dacelo leachii intermedia Salvadori (blue-winged kookaburra); E. reninoda n. sp. ex Melidora macrorrhina macrorhina Lesson (hook-billed kingfisher); and E. persei n. sp. ex Tanysiptera danae Sharpe (brown-headed paradise-kingfisher). In addition, we illustrate Emersoniella regis Emerson & Price, Emersoniella halcyonis Tendeiro, and the male genitalia of Emersoniella galateae Emerson & Price, as well as provide a complete host-louse checklist, and an updated key to all seven species of this genus. 


Assuntos
Aves/parasitologia , Iscnóceros/classificação , Animais , Lista de Checagem , Feminino , Iscnóceros/anatomia & histologia , Masculino , Papua Nova Guiné , Especificidade da Espécie
11.
J Parasitol ; 110(2): 143-149, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561014

RESUMO

Birds have a diverse community of "permanent" arthropods that complete their entire life cycle on the body of the host. Because some of these arthropods are parasites that reduce host fitness, birds control them by grooming, which consists of preening with the beak and scratching with the feet. Although preening is the primary component of grooming, scratching is essential for controlling arthropods on the head and neck, which cannot be preened. Several unrelated groups of birds have evolved comb-like pectinate claws on the middle toenail of each foot. We tested the role of these claws in the control of arthropods by experimentally removing teeth from the claws of captive western cattle egrets (Bubulcus ibis) infested with chewing lice (Insecta: Phthiraptera), feather mites (Acari: Sarcoptiformes), and nasal mites (Acari: Mesostigmata). After a period of 4 mo, we compared the abundance of arthropods on experimental birds to that of control birds with intact teeth. We used video to quantify the grooming rates of the captive birds, which groomed twice as much as wild birds. Experimental and control birds did not differ significantly in grooming time. Both groups virtually eradicated the chewing lice, but not feather mites or nasal mites. We found no support for the hypothesis that pectinate claws increase the efficiency of arthropod control by grooming. Experiments with wild birds are needed to test the hypothesis further under conditions in which birds devote less time to grooming.


Assuntos
Ácaros e Carrapatos , Artrópodes , Doenças das Aves , Infestações por Piolhos , Ftirápteros , Animais , Bovinos , Infestações por Piolhos/veterinária , Infestações por Piolhos/parasitologia , Asseio Animal , Doenças das Aves/parasitologia , Aves , Animais Selvagens
12.
Ecol Evol ; 14(9): e70280, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39267692

RESUMO

Environmental factors such as temperature and humidity influence the distribution of free-living organisms. As climates change, the distributions of these organisms change along with their associated parasites, mutualists and commensals. Less studied, however, is the possibility that environmental conditions may directly influence the distribution of these symbionts even if the hosts are able to persist in altered environments. Here, we investigate the diversity of parasitic lice (Insecta: Phthiraptera) on birds in arid Utah compared to the humid Bahamas. We quantified the parasite loads of 500 birds. We found that the prevalence, abundance and richness of lice was considerably lower among birds in Utah, compared to the Bahamas, despite sampling greater host taxonomic richness in Utah. Our data suggest that as climates change, birds in arid regions will have less diverse louse communities over time, potentially relieving birds of some of the cost of controlling these ectoparasites. Conversely, birds in more humid regions will see an increase in louse diversity, which may require them to invest more time and energy in anti-parasite defense. Additional research with other ectoparasites of birds and mammals across different environmental conditions is needed to more fully understand how climate change may reshape parasite communities, and how these changes could influence their hosts.

13.
Nat Commun ; 15(1): 4571, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811551

RESUMO

Evolution results from the interaction of stochastic and deterministic processes that create a web of historical contingency, shaping gene content and organismal function. To understand the scope of this interaction, we examine the relative contributions of stochasticity, determinism, and contingency in shaping gene inactivation in 34 lineages of endosymbiotic bacteria, Sodalis, found in parasitic lice, Columbicola, that are independently undergoing genome degeneration. Here we show that the process of genome degeneration in this system is largely deterministic: genes involved in amino acid biosynthesis are lost while those involved in providing B-vitamins to the host are retained. In contrast, many genes encoding redundant functions, including components of the respiratory chain and DNA repair pathways, are subject to stochastic loss, yielding historical contingencies that constrain subsequent losses. Thus, while selection results in functional convergence between symbiont lineages, stochastic mutations initiate distinct evolutionary trajectories, generating diverse gene inventories that lack the functional redundancy typically found in free-living relatives.


Assuntos
Evolução Molecular , Genoma Bacteriano , Filogenia , Processos Estocásticos , Simbiose , Simbiose/genética , Genoma Bacteriano/genética , Animais , Enterobacteriaceae/genética , Enterobacteriaceae/metabolismo , Mutação
14.
Appl Environ Microbiol ; 79(9): 2952-61, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23435889

RESUMO

Bat flies are a diverse clade of obligate ectoparasites on bats. Like most blood-feeding insects, they harbor endosymbiotic prokaryotes, but the origins and nature of these symbioses are still poorly understood. To expand the knowledge of bacterial associates in bat flies, the diversity and evolution of the dominant endosymbionts in six of eight nominal subfamilies of bat flies (Streblidae and Nycteribiidae) were studied. Furthermore, the localization of endosymbionts and their transmission across developmental stages within the family Streblidae were explored. The results show diverse microbial associates in bat flies, with at least four ancestral invasions of distantly related microbial lineages throughout bat fly evolution. Phylogenetic relationships support the presence of at least two novel symbiont lineages (here clades B and D), and extend the geographic and taxonomic range of a previously documented lineage ("Candidatus Aschnera chinzeii"; here clade A). Although these lineages show reciprocally monophyletic clusters with several bat fly host clades, their phylogenetic relationships generally do not reflect current bat fly taxonomy or phylogeny. However, within some endosymbiont clades, congruent patterns of symbiont-host divergence are apparent. Other sequences identified in this study fall into the widely distributed, highly invasive, insect-associated Arsenophonus lineage and may be the result of symbiont replacements and/or transient infections (here clade C). Vertical transmission of endosymbionts of clades B and D is supported by fluorescent signal (fluorescent in situ hybridization [FISH]) and microbial DNA detection across developmental stages. The fluorescent bacterial signal is consistently localized within structures resembling bacteriomes, although their anatomical position differs by host fly clade. In summary, the results suggest an obligate host-endosymbiont relationship for three of the four known symbiont clades associated with bat flies (clades A, B, and D).


Assuntos
Quirópteros/parasitologia , Dípteros/microbiologia , Enterobacteriaceae/genética , Animais , Proteínas de Bactérias/genética , Sequência de Bases , Evolução Biológica , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dípteros/citologia , Enterobacteriaceae/classificação , Enterobacteriaceae/isolamento & purificação , Feminino , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Geografia , Hibridização in Situ Fluorescente , Masculino , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Simbiose
15.
Syst Parasitol ; 85(1): 11-26, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23595488

RESUMO

The genus Pseudoacanthocephalus Petrochenko, 1958 currently includes 14 species of acanthocephalans parasitic in amphibians and reptiles worldwide. This work describes two new species of Pseudoacanthocephalus from amphibians and reptiles collected in several localities on Luzon Island, Philippines. Pseudoacanthocephalus nickoli n. sp. was found in two species of frogs, Rana luzonensis Boulenger and Rana similis (Günther), and Pseudoacanthocephalus smalesi n. sp. was found in a scincid lizard, Sphenomorphus abdictus Brown & Alcala. Differential diagnoses of the two new species of Pseudoacanthocephalus from their congeners are provided. Comparative analysis of nuclear ribosomal rRNA sequences encompassing the 3' end of 18S nuclear rDNA gene, internal transcribed spacer region (ITS1+5.8S+ITS2), and 5' end of the 28S gene strongly corroborated the morphological evidence and demonstrated significant differences between the two new species as well as between these species and closely related species from continental China and Vietnam. No intraspecific sequence variability was detected among different individuals representing each of the examined species. This is the first report of Pseudoacanthocephalus in the Philippines. A key to known species of Pseudoacanthocephalus is provided.


Assuntos
Acantocéfalos/classificação , Acantocéfalos/isolamento & purificação , Anfíbios/parasitologia , Répteis/parasitologia , Acantocéfalos/genética , Acantocéfalos/ultraestrutura , Animais , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Microscopia , Dados de Sequência Molecular , Filipinas , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
16.
Syst Parasitol ; 86(2): 165-71, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24048748

RESUMO

Two new species of Eimeria Schneider, 1875, from emerald tree skinks, Lamprolepis smaragdina (Lesson) are described from specimens collected in Papua New Guinea (PNG) and the Philippines. Oöcysts of Eimeria nuiailan n. sp. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bi-layered wall, measure 23.7 × 19.1 µm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal to ellipsoidal, 11.9 × 7.0 µm, L/W 1.7, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is present as a compact mass of granules. Sporozoites are elongate, 14.6 × 2.6 µm, and contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Eimeria auffenbergi n. sp. from L. smaragdina collected in the Philippines are ovoidal, with a smooth, colourless, bi-layered wall, measure 19.9 × 15.8 µm, L/W 1.3; both micropyle and oöcyst residuum are absent, but one to four polar granules are present. Sporocysts are ovoidal to ellipsoidal, 10.3 × 5.8 µm, L/W 1.8, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is composed of dispersed granules.


Assuntos
Eimeria/classificação , Eimeria/citologia , Lagartos/parasitologia , Animais , Coccidiose/parasitologia , Fezes/parasitologia , Papua Nova Guiné , Filipinas , Especificidade da Espécie
17.
J Parasitol ; 109(3): 145-147, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37129982

RESUMO

Animals defend themselves against parasites in many ways. Defenses, such as physiological immune responses, are capable of clearing some infections. External parasites that do not feed on blood, however, are not controlled by the physiological immune system. Instead, ectoparasites like feather-feeding lice (Phthiraptera: Ischnocera) are primarily controlled by behavioral defenses such as preening. Here we test the hypothesis that birds able to preen are capable of clearing infestations of feather lice. We experimentally manipulated preening ability in a captive population of rock pigeons (Columba livia) that were infested with identical numbers of feather lice (Columbicola columbae or Campanulotes compar or both). We then monitored the feather louse infestations for 42 wk. Birds with impaired preening remained infested throughout the experiment; in contrast, the prevalence of lice on birds that could preen normally decreased by 50%. These data indicate that it is indeed possible for birds to clear themselves of feather lice, and perhaps other ectoparasites, by preening. We note, however, that captive birds spend more time preening than wild birds, and that they are less likely to be reinfested than wild birds. Thus, additional studies are necessary to determine under what circumstances wild birds can clear themselves of ectoparasites by preening.


Assuntos
Doenças das Aves , Iscnóceros , Infestações por Piolhos , Animais , Infestações por Piolhos/epidemiologia , Infestações por Piolhos/prevenção & controle , Infestações por Piolhos/veterinária , Columbidae/parasitologia , Asseio Animal/fisiologia , Prevalência , Doenças das Aves/epidemiologia , Doenças das Aves/prevenção & controle , Doenças das Aves/parasitologia , Animais Selvagens
18.
Zootaxa ; 5104(4): 506-530, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35391023

RESUMO

Six new species of chewing lice in the Resartor-group (Brueelia-complex) are described and illustrated. They are: Aratricerca cerata n. sp. ex Zosterops capensis Sundevall, 1850; Aratricerca macki n. sp. ex Melidectes princeps Mayr Gilliard, 1951 and Ptiloprora perstriata perstriata (de Vis, 1898); Aratricerca madagascariensis n. sp. ex Randia pseudozosterops Delacour Berlioz, 1931; Turdinirmoides janigai n. sp. ex Prunella collaris nipalensis (Blyth, 1843) and P. collaris fennelli Deignan, 1964; Turdinirmoides rozsai n. sp. ex Carpodacus subhimachala (Hodgson, 1836); and Timalinirmus curvus n. sp. ex Yuhina castaniceps plumbeiceps (Godwin-Austen, 1877). A key to the species of Aratricerca, Turdinirmoides and Timalinirmus is provided.


Assuntos
Doenças das Aves , Iscnóceros , Infestações por Piolhos , Passeriformes , Ftirápteros , Animais , Infestações por Piolhos/veterinária
19.
Zootaxa ; 5165(1): 1-55, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-36095483

RESUMO

Fourteen new species of chewing lice in the Brueelia-complex are described, from hosts in the Campephagidae. In addition, Malardifax a new subgenus of Guimaraesiella Eichler, 1949 is described for the species occurring on minivets (Campephagidae: Pericrocotus). The new species and their hosts are: Guimaraesiella (Guimaraesiella) nouankaoensis n. sp. from Coracina caledonica seiuncta Mayr Ripley, 1941 and C. caledonica thilenii (Neumann, 1915); Guimaraesiella (Guimaraesiella) sphagmotica n. sp. from Coracina caeruleogrisea strenua (Schlegel, 1871) and C. caeruleogrisea adamsoni Mayr Rand, 1936; Indoceoplanetes (Capnodella) kamphaengphetensis n. sp. from Lalage melaschistos avensis (Blyth, 1852); Indoceoplanetes (Capnodella) saucia n. sp. from Edolisoma montanum montanum (Meyer, 1874); Indoceoplanetes (Capnodella) subarcens n. sp. from Edolisoma melas melas (Lesson, 1828); Indoceoplanetes (Indoceoplanetes) cinitemnina n. sp. from Edolisoma melas melas (Lesson, 1828); Indoceoplanetes (Indoceoplanetes) ephippiformis n. sp. from Edolisoma montanum montanum (Meyer, 1874); Indoceoplanetes (Indoceoplanetes) fodincana n. sp. from Coracina papuensis oriomo Mayr Rand, 1936, C. papuensis angustifrons (Salvadori, 1876), and C. papuensis elegans (Ramsay, 1881); Indoceoplanetes (Indoceoplanetes) incisoma n. sp. from Coracina macei siamensis (Baker, 1918) and C. macei rexpineti (Swinhoe, 1863); Indoceoplanetes (Indoceoplanetes) microgenitalis n. sp. from Coracina caeruleogrisea strenua (Schlegel, 1871); Indoceoplanetes (Indoceoplanetes) pterophora n. sp. from Coracina macei nipalensis (Hodgson, 1836); Indoceoplanetes (Indoceoplanetes) saburrata n. sp. from Coracina lineata ombriosa (Rothschild Hartert, 1905); Indoceoplanetes (Indoceoplanetes) wandoensis n. sp. from Coracina novaehollandiae melanops (Latham, 1802); and Indoceoplanetes (Indoceoplanetes) zambica n. sp. from Coracina pectoralis (Jardine Selby, 1828). Checklists and keys to the louse species of the Brueelia-complex parasitic on campephagid hosts are provided.


Assuntos
Doenças das Aves , Iscnóceros , Infestações por Piolhos , Síndrome MELAS , Passeriformes , Animais , Doenças das Aves/parasitologia , Infestações por Piolhos/parasitologia , Infestações por Piolhos/veterinária , Passeriformes/parasitologia
20.
Front Immunol ; 13: 879686, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711435

RESUMO

Neutrophils play a significant role in determining disease severity following SARS-CoV-2 infection. Gene and protein expression defines several neutrophil clusters in COVID-19, including the emergence of low density neutrophils (LDN) that are associated with severe disease. The functional capabilities of these neutrophil clusters and correlation with gene and protein expression are unknown. To define host defense and immunosuppressive functions of normal density neutrophils (NDN) and LDN from COVID-19 patients, we recruited 64 patients with severe COVID-19 and 26 healthy donors (HD). Phagocytosis, respiratory burst activity, degranulation, neutrophil extracellular trap (NET) formation, and T-cell suppression in those neutrophil subsets were measured. NDN from severe/critical COVID-19 patients showed evidence of priming with enhanced phagocytosis, respiratory burst activity, and degranulation of secretory vesicles and gelatinase and specific granules, while NET formation was similar to HD NDN. COVID LDN response was impaired except for enhanced NET formation. A subset of COVID LDN with intermediate CD16 expression (CD16Int LDN) promoted T cell proliferation to a level similar to HD NDN, while COVID NDN and the CD16Hi LDN failed to stimulate T-cell activation. All 3 COVID-19 neutrophil populations suppressed stimulation of IFN-γ production, compared to HD NDN. We conclude that NDN and LDN from COVID-19 patients possess complementary functional capabilities that may act cooperatively to determine disease severity. We predict that global neutrophil responses that induce COVID-19 ARDS will vary depending on the proportion of neutrophil subsets.


Assuntos
COVID-19 , Armadilhas Extracelulares , Armadilhas Extracelulares/metabolismo , Humanos , Neutrófilos/metabolismo , Explosão Respiratória , SARS-CoV-2
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