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1.
Parasit Vectors ; 15(1): 187, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655262

RESUMO

BACKGROUND: Changes in host phenotype following parasite infection are often considered as host manipulation when they seem advantageous for the parasite. However, putative cases of host manipulation by parasites are rarely tested in field-realistic conditions. Infection-induced phenotypic change cannot be conclusively considered as host manipulation if no evidence shows that this trait is adaptive for the parasite in the wild. Plasmodium sp., the parasites causing malaria in vertebrates, are hypothesized to "manipulate" their host by making their odour more attractive to mosquitoes, their vector and final host. While this is fairly well supported by studies on mice and humans, studies focusing on avian malaria give contradictory results. METHODS: In the present study, genotyped birds at different stages (uninfected, acute and chronic) of Plasmodium relictum infection were exposed, in a large outdoor aviary, to their natural vector, the mosquito Culex pipiens. RESULTS: After genotyping the blood meals of more than 650 mosquitoes, we found that mosquitoes did not bite infected birds more than they bit them before infection, nor more than they bit uninfected hosts. CONCLUSIONS: Our study highlights the importance of testing ecological behaviours under natural conditions and suggests that different processes might be at play in mammals and birds regarding potential manipulation of attractiveness by malaria parasites.


Assuntos
Aves , Mordeduras e Picadas , Culicidae , Malária Aviária , Animais , Aves/parasitologia , Mordeduras e Picadas/veterinária , Mosquitos Vetores
2.
Vet Parasitol Reg Stud Reports ; 31: 100652, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35569906

RESUMO

Avian Haemosporidian parasites - Plasmodium, Haemoproteus, Leucocytozoon and Fallisia - have a wide distribution except for Antarctica. Leucocytozoon sp. has been poorly described in Brazil, and few studies have indicated infections in birds from the Atlantic Forest, Pantanal, Pampa and Amazon biomes. This study describes, for the first time, the occurrence of Leucocytozoon infection in red-legged seriemas (Cariama cristata) in the Brazilian savanna (Cerrado biome) using molecular diagnosis. Leucocytozoon spp. lineage CARCRI01 was detected in three C. cristata, a non-migratory bird, confirming transmission in mid-elevation areas in central Brazil. Further studies are needed to certify whether infections in red-legged seriemas were not abortive and to elucidate Leucocytozoon infection at low altitudes in the Brazilian lands.


Assuntos
Doenças das Aves , Haemosporida , Animais , Doenças das Aves/parasitologia , Aves/parasitologia , Brasil/epidemiologia , Filogenia
3.
Int J Parasitol ; 52(8): 525-537, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35439499

RESUMO

Philopteridae feather lice are a group of ectoparasitic insects which have intimate relationships with their avian hosts. Feather lice include an enormous number of described species; however, the relationships of major lineages have been clouded by homoplasious characters due to convergent evolution. In this study, a comprehensive phylogenomic analysis of the group is performed which includes 137 feather louse species. Several other analyses are also completed including dating analysis, cophylogenetic reconstructions, and ancestral character estimation to understand the evolution of complex morphological and ecological traits. Phylogenetic results recover high support for the placement of major feather louse lineages, but with lower support for long-branched enigmatic genera found at the base of the tree. The results of dating analyses suggest modern feather lice began to diversify approximately 49 million years ago following the adaptive radiation of their avian hosts. Cost-based cophylogenetic reconstructions recover a high frequency of host switching, while congruence-based methods indicate a significant level of congruence between host and parasite trees. Ancestral state reconstructions favour a generalist ancestor and water bird host at the root. The analyses completed provide insight into the evolution of a diverse group of ectoparasitic insects which infest a wide variety of avian hosts. The results represent the most comprehensive phylogenetic hypothesis of the group to date and provide a framework for future classification of the family into natural groupings.


Assuntos
Interações Hospedeiro-Parasita , Ftirápteros , Animais , Aves/parasitologia , Neópteros , Ftirápteros/genética , Filogenia
4.
Sci Rep ; 12(1): 6892, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477963

RESUMO

Haemosporidian parasites are common in birds but are seldom reported in seabirds. The absence of vectors or genetic resistance to infection have been proposed to explain this pattern. However, screening of blood parasites in many seabirds has been done only by visual inspection of blood smears, which can miss low-intensity infections, and molecular detection of blood parasites must be supported by detection in blood smears to confirm the presence of haemosporidians and avoid false positive cases. Here, we tested for the presence of blood parasites of the genera Plasmodium, Haemoproteus and Leucocytozoon, combining inspection of blood smears and PCR-based detection methods in a highly philopatric colony of blue-footed boobies (Sula nebouxii) in the Tropical North Pacific. Our results indicate that adults in this colony are likely free of these blood parasites, probably due to unsuitable conditions for insect vectors in booby breeding sites, although potential genetic resistance of blue-footed boobies to infection deserves examination. Apparent absence of blood parasites in Isla Isabel boobies indirectly adds to the growing evidence of variation in parasite infections among avian host species that coexist locally.


Assuntos
Haemosporida , Malária Aviária , Parasitos , Animais , Aves/parasitologia , Cruzamento , Haemosporida/genética , Malária Aviária/parasitologia
5.
Parasitol Res ; 121(6): 1775-1787, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35435509

RESUMO

Avian haemosporidian from the genera Haemoproteus and Plasmodium are a diverse and widely distributed group of vector-borne blood parasites. These parasites can have negative effects on bird survival by influencing several aspects of their life cycle, causing different clinical signs and even death. Colombia has the widest range of bird richness throughout the globe; however, the associations between haemosporidian parasites and wild birds in different ecosystems remain poorly explored. Within this frame of reference, the objective of the present study was to identify and understand haemosporidian associated with resident and migratory wild birds and their lineages in northeast Orinoquia region, Colombia. Birds were captured in 8 localities and blood samples were collected, identifying the presence of haemosporidian parasites through morphological and molecular analysis of the mitochondrial cytochrome b gene. Blood samples from 233 wild birds (86 species) were analyzed for haemosporidian parasites. Sixteen individuals (6.9%) from 15 resident and migratory species were positive for Haemoproteus or Plasmodium. Fourteen haemosporidian lineages were identified, five of them reported for the first time. These new lineages are reported in four resident birds and one boreal migratory bird (Parkesia noveboracensis). This study is the first developed in the department of Arauca and contributes to the knowledge of haemosporidian lineages and their interaction with wild birds in the Colombian Orinoquia region and South America.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Infecções Protozoárias em Animais , Animais , Animais Selvagens , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Colômbia/epidemiologia , Ecossistema , Haemosporida/genética , Humanos , Filogenia , Plasmodium/genética , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia
6.
Parasitol Res ; 121(7): 1921-1935, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35488923

RESUMO

Patagifer Dietz, 1909 is a small genus of echinostomatids, with 12 recognized species, mostly parasitising threskiornithid birds, distributed worldwide. In the current research, adult specimens of the type species, Patagifer bilobus (Rudolphi, 1819) Dietz, 1909 from the white faced ibis (Plegadis chihi) and white ibis (Eudocimus albus) were re-described, providing new metrical data for the number of head collar spines. Those specimens were recorded from eight localities in Mexico and compared morphologically with specimens previously identified as Patagifer lamothei. A total of 19 specimens identified as P. bilobus including two hologenophores were sequenced with three molecular markers: domains D1-D3 of the large subunit (LSU), the internal transcribed spacer (ITS1, ITS2) plus 5.8S from the nuclear rDNA, and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (nad1) from mitochondrial DNA. The new sequences were aligned with other sequences of Patagifer spp., downloaded from GenBank. Phylogenetic trees inferred from each data set, placed all the specimens in a clade, confirming that the isolates belonged to the same species. The morphological examination of specimens previously identified as P. lamothei by Ortega-Olivares MP, Hernández-Mena DI, Pérez-Ponce de León G, García-Varela M (2011) Helminths of the white ibis, Eudocimus albus (Aves Therskiornithidae) in Mexico. (Zootaxa 3088, 15-26. 10.11646/zootaxa.3088.1.2) and in combination with molecular data confirms that those specimens should be reassigned to P. bilobus. In addition, this is the first study in P. bilobus using an integrative taxonomy approach.


Assuntos
Echinostomatidae , Trematódeos , Animais , Aves/parasitologia , DNA de Helmintos/genética , DNA Ribossômico/genética , Echinostomatidae/genética , México , Filogenia
7.
Biol Lett ; 18(4): 20210575, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35414225

RESUMO

The factors that influence whether a parasite is likely to cause death in a given host species are not well known. Generalist parasites with high local abundances, broad distributions and the ability to infect a wide phylogenetic diversity of hosts are often considered especially dangerous for host populations, though comparatively little research has been done on the potential for specialist parasites to cause host mortality. Here, using a novel database of avian mortality records, we tested whether phylogenetic host specialist or host generalist haemosporidian blood parasites were associated with avian host deaths based on infection records from over 81 000 examined hosts. In support of the hypothesis that host specialist parasites can be highly virulent in novel hosts, we found that the parasites that were associated with avian host mortality predominantly infected more closely related host species than expected under a null model. Hosts that died tended to be distantly related to the host species that a parasite lineage typically infects, illustrating that specialist parasites can cause death outside of their limited host range. Overall, this study highlights the overlooked potential for host specialist parasites to cause host mortality despite their constrained ecological niches.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Animais , Doenças das Aves/parasitologia , Aves/parasitologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Filogenia
8.
J Parasitol ; 108(2): 209-216, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35435986

RESUMO

The genus Eustrongylides includes zoonotic nematodes that infect fish species and fish-eating birds of freshwater ecosystems. This study aimed to evaluate the occurrence of Eustrongylides in the paratenic host Perca fluviatilis (European perch) and in the definitive host, Phalacrocorax carbo sinensis (great cormorant), in Lake Annone, a shallow eutrophic lake located in the pre-mountainous area of the Alps in northwest Italy where wintering cormorants coexist with new breeding colonies. A total of 114 European perch and 48 cormorants were examined for the occurrence of Eustrongylides. All parasites collected were identified with microscopic examination and molecular analysis. Overall, 11 specimens of European perch (9.6%) and 13 individuals of cormorants (27%) harbored nematodes identified as fourth-stage larvae and adults of Eustrongylides excisus. The observed prevalence of Eustrongylides spp. appears to be intermediate between the higher values in cormorant breeding areas in northern Europe and the lower prevalence observed in their wintering sites in southernmost Europe. Considering the eutrophication status of freshwater ecosystems and the increasing population of the cormorants, Eustrongylides has an increasing potential range of dispersion in Europe, including Italy; thus an extensive surveillance should be carried out, especially given the zoonotic potential of this nematode.


Assuntos
Dioctophymatoidea , Helmintos , Nematoides , Percas , Animais , Aves/parasitologia , Ecossistema , Lagos , Percas/parasitologia
9.
J Parasitol ; 108(2): 100-106, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35240687

RESUMO

The brown booby (Sula leucogaster Boddaert, 1783) has a wide geographic distribution, being found throughout the intertropical range except for the west coast of South America. Chewing lice (Phthiraptera: Amblycera and Ischnocera) are ectoparasites commonly found in association with a wide variety of bird species, and extensive infestations can lead to severe itching and irritation that causes skin lesions, damage to the plumage, and abandonment of nests. Sula leucogaster lice have an atypical distribution, not fully following the distribution of their host. In the years 2018 and 2019, 4 marine animal rehabilitation centers located in Rio de Janeiro and São Paulo, Brazil received live birds and carcasses of Sula leucogaster. The animals were deloused and lice of 2 different species were collected. Identification was performed by optical microscopy, and the species found were Eidmanniella albescens Piaget, 1880 and Pectinopygus garbeiPessoa and Guimarães, 1935. This is the first record of both species in Rio de Janeiro.


Assuntos
Amblíceros , Doenças das Aves , Iscnóceros , Infestações por Piolhos , Ftirápteros , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Brasil/epidemiologia , Infestações por Piolhos/epidemiologia , Infestações por Piolhos/parasitologia , Infestações por Piolhos/veterinária
10.
Syst Parasitol ; 99(3): 347-365, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35320484

RESUMO

The type-species of the genus Diorchis Clerc, 1903, D. acuminata (Clerc, 1902) Clerc, 1903, is re-described and illustrated on the basis of the type-material from Fulica atra L. from the Middle Ural, Russia, and new specimens from the same host species from Bulgaria. Since the type-series consists of specimens of two species, a syntype is designated as lectotype. The main differentiating characters of D. acuminata are the diorchoid rostellar hooks, 36-39 µm long, with a foliate epiphyseal thickening of the guard; cirrus-sac of variable length, usually reaching and often crossing the midline of proglottis, occasionally reaching antiporal osmoregulatory canals; evaginated cirrus with cylindrical basal part, bulbous middle part and pipette-like distal part; compact vitellarium situated dorsally to the ovary; copulatory part of vagina with muscular poral and middle portions and an antiporal sac-like reservoir; elongate eggs with polar filaments on their envelopes. The type-specimens of D. ransomi Johri, 1939 and D. longibursa Steelman, 1939 from Fulica americana Gmelin from USA are also re-examined and illustrated. Based on the present results, D. ransomi and D. longibursa are recognised as synonyms of D. acuminata. The previous records of the species are discussed. Diorchis acuminata is recognised as a specific parasite of Rallidae (mainly species of the genera Fulica and Gallinula) in the Holarctic.


Assuntos
Cestoides , Animais , Aves/parasitologia , Feminino , Federação Russa , Especificidade da Espécie
11.
Front Immunol ; 13: 807682, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250978

RESUMO

Natural antibodies (Abs), produced in response to bacterial gut microbiota, drive resistance to infection in vertebrates. In natural systems, gut microbiota diversity is expected to shape the spectrum of natural Abs and resistance to parasites. This hypothesis has not been empirically tested. In this 'Hypothesis and Theory' paper, we propose that enteric microbiota diversity shapes the immune response to the carbohydrate α-Gal and resistance to avian malaria. We further propose that anti-α-Gal Abs are transmitted from mother to eggs for early malaria protection in chicks. Microbiota modulation by anti-α-Gal Abs is also proposed as a mechanism favoring the early colonization of bacterial taxa with α1,3-galactosyltransferase (α1,3GT) activity in the bird gut. Our preliminary data shows that bacterial α1,3GT genes are widely distributed in the gut microbiome of wild and domestic birds. We also showed that experimental infection with the avian malaria parasite P. relictum induces anti-α-Gal Abs in bird sera. The bird-malaria-microbiota system allows combining field studies with infection and transmission experiments in laboratory animals to test the association between microbiota composition, anti-α-Gal Abs, and malaria infection in natural populations of wild birds. Understanding how the gut microbiome influences resistance to malaria can bring insights on how these mechanisms influence the prevalence of malaria parasites in juvenile birds and shape the host population dynamics.


Assuntos
Malária Aviária , Malária , Microbiota , Animais , Animais Selvagens , Bactérias , Aves/parasitologia , Malária/veterinária , Malária Aviária/epidemiologia , Malária Aviária/parasitologia
12.
J Wildl Dis ; 58(2): 373-379, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35290458

RESUMO

Parasites have developed many strategies to ensure their development, multiplication, and dissemination, including the use of reservoir hosts that are often nondomesticated species. Despite drastic reductions in their populations, wild birds remain widespread worldwide and could constitute some of these reservoirs. We focused on the identification of wild bird species harboring parasite stages in their muscles. Breast muscles of 327 birds of 27 different species were collected at three different sites in France. After artificial digestion, isolated nematode larvae were identified by PCR sequencing or restriction fragment length polymorphism (PCR-RFLP). Toxocara cati was identified mainly in birds of prey. The presence of anti-Toxoplasma antibodies was investigated by modified agglutination test on muscle fluids. Anti-Toxoplasma antibodies were detected in 65 out of 166 samples from various bird species. Avifauna, particularly birds of prey, could help on the surveillance of parasite circulation and play a role as sentinel species.


Assuntos
Doenças das Aves , Aves Predatórias , Toxoplasma , Toxoplasmose Animal , Animais , Animais Selvagens/parasitologia , Anticorpos Antiprotozoários , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Toxocara , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologia
13.
Parasitol Res ; 121(3): 1059-1063, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35156145

RESUMO

Parasitism in kingfishers is very little reported and predominantly related to hemoparasites, helminths, and ectoparasites. The present study provided a morphological and genotypic study of an Eimeria sp. recovered from a green kingfisher Chloroceryle americana (Gmelin, 1788) captured in the Marambaia Island, on the coast of the state of Rio de Janeiro, Southeastern Brazil. The coccidial density, some morphological aspects of its oocysts, the molecular results, and, mainly, the ecological niche of C. americana in the mangrove of the Marambaia Island suggest that this coccidian species is a pseudoparasite.


Assuntos
Coccidiose , Eimeria , Animais , Aves/parasitologia , Brasil , Coccidiose/parasitologia , Coccidiose/veterinária , Eimeria/genética , Oocistos
14.
Parasitol Res ; 121(5): 1407-1417, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35106653

RESUMO

Avian haemosporidians from the genera Plasmodium and Haemoproteus are vector transmitted parasites. A growing body of evidence suggests that variation in their prevalence within avian communities is correlated with a variety of avian ecological traits. Here, we examine the relationship between infection probability and diversity of haemosporidian lineages and avian host ecological traits (average body mass, foraging stratum, migratory behavior, and nest type). We used molecular methods to detect haemosporidian parasites in blood samples from 642 individual birds of 149 species surveyed at four localities in the Brazilian Pantanal. Based on cytochrome b sequences, we recovered 28 lineages of Plasmodium and 17 of Haemoproteus from 31 infected avian species. Variation in lineage diversity among bird species was not explained by avian ecological traits. Prevalence was heterogenous across avian hosts. Bird species that forage near the ground were less likely to be infected by Haemoproteus, whereas birds that build open cup nests were more likely infected by Haemoproteus. Furthermore, birds foraging in multiple strata were more likely to be infected by Plasmodium. Two other ecological traits, often related to host resistance (body mass and migratory behavior), did not predict infection probability among birds sampled in the Pantanal. Our results suggest that avian host traits are less important determinants of haemosporidian diversity in Pantanal than in other regions, but reinforces that host attributes, related to vector exposure, are to some extent important in modulating infection probability within an avian host assemblage.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Infecções Protozoárias em Animais , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Filogenia , Plasmodium/genética , Prevalência , Infecções Protozoárias em Animais/epidemiologia
15.
Sci Rep ; 12(1): 2325, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149738

RESUMO

Many parasites of seasonally available hosts must persist through times of the year when hosts are unavailable. In tropical environments, host availability is often linked to rainfall, and adaptations of parasites to dry periods remain understudied. The bird-parasitic fly Philornis downsi has invaded the Galapagos Islands and is causing high mortality of Darwin's finches and other bird species, and the mechanisms by which it was able to invade the islands are of great interest to conservationists. In the dry lowlands, this fly persists over a seven-month cool season when availability of hosts is very limited. We tested the hypothesis that adult flies could survive from one bird-breeding season until the next by using a pterin-based age-grading method to estimate the age of P. downsi captured during and between bird-breeding seasons. This study showed that significantly older flies were present towards the end of the cool season, with ~ 5% of captured females exhibiting estimated ages greater than seven months. However, younger flies also occurred during the cool season suggesting that some fly reproduction occurs when host availability is low. We discuss the possible ecological mechanisms that could allow for such a mixed strategy.


Assuntos
Aves/parasitologia , Cruzamento , Interações Hospedeiro-Parasita , Muscidae/fisiologia , Envelhecimento , Animais , Aves/fisiologia , Diapausa/fisiologia , Equador , Feminino , Estágios do Ciclo de Vida , Masculino , Pupa , Estações do Ano
16.
Int J Parasitol ; 52(1): 87-96, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34450133

RESUMO

Tropical forest degradation affects host-parasite interactions, determining the probability of animals acquiring an infection. The activation of an immune response to fight off infections requires energy and other resources such as antioxidants which may be redirected from growth and reproduction. A key question is how selective logging-the most common form of tropical forest degradation-impacts the prevalence of avian haemosporidian infection and its correlated physiological responses (nutritional and oxidative status markers). We investigated the prevalence of Plasmodium, Haemoproteus, and Leucocytozoon parasites in 14 understorey bird species in lowland, logged and unlogged, old-growth forests of Borneo. Prevalences of infections were similar between selectively logged and unlogged forests. To explore nutritional and oxidative status effects of haemosporidian infections, we examined associations between infections and plasma proteins, plasma triglycerides, and multiple blood-based markers of oxidative status, testing for an impact of selective logging on those markers. Birds infected with Plasmodium showed higher levels of plasma proteins and non-enzymatic antioxidant capacity, and lower levels of plasma triglycerides and glutathione, compared with haemosporidian-free individuals. Conversely, birds infected with Haemoproteus showed no changes in nutritional or physiological markers compared with uninfected individuals. These results indicate higher metabolic and physiological costs of controlling Plasmodium infection, compared with Haemoproteus, possibly due to higher pathogenicity of Plasmodium. Selectively logged forests had no effect on the responses of birds to infection, suggesting that the environmental conditions of degraded forests do not appear to induce any appreciable physiological demands in parasitised birds.


Assuntos
Doenças das Aves , Haemosporida , Plasmodium , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Prevalência , Triglicerídeos
17.
Parasitology ; 149(4): 469-481, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34814964

RESUMO

Many parasites spend part of their life cycle as infectious forms released from an infected host in the external environment, where they may encounter and infect new hosts. The emergence of infectious life stages often occurs once a day to minimize mortality in adverse environments. In bird hosts, intestinal parasites such as coccidia are generally released with feces in the late afternoon. This dynamic is adaptive since it allows avoiding desiccation and ultraviolet (UV) radiation, thus reducing mortality of oocysts in the environment until transmission to the next host. If this circadian rhythm is the result of natural selection to increase oocyst survival, we may hypothesize that oocysts will appear in feces at different times depending on the environment where hosts live. Particularly, in an environment where UV radiation and desiccation are very low, we may expect oocyst circadian release to disappear since the main selective pressure would be relaxed. We sampled different species of birds in tropical and temperate forests in spring and investigated coccidian oocyst output. A strong circadian variation in the prevalence of hosts shedding coccidian oocyst was detected for species caught in the temperate forest with an increase in prevalence in the late afternoon, whereas prevalence of birds shedding oocysts was constant over the course of the day for most species sampled in the tropical rain forest. These results are consistent with the hypothesis that oocysts' circadian output is maintained by natural selection to increase oocyst survival. We discuss the adaptive significance of diurnal periodicity in parasite output.


Assuntos
Coccídios , Coccidiose , Parasitos , Animais , Aves/parasitologia , Coccidiose/parasitologia , Coccidiose/veterinária , Fezes/parasitologia , Oocistos
18.
Vet Parasitol Reg Stud Reports ; 26: 100622, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34879934

RESUMO

Netta peposaca is an anatid endemic to the South American continent and Rhinonyssus rhinolethrum is a rhinonissid mite of wide geographical distribution parasitizing several species of anatids. The association between these organisms has been reported in Argentina; however, the number of birds examined and the parasite indices have not been reported. Thus, the objective of this study was to know the diversity of nasal mites associated with N. peposaca in southern of Brazil and the parasitological indices. The nasal cavities of 30 birds from two locations in Rio Grande do Sul, Brazil, were examined to collect mites. Rhinonyssus rhinolethrum occurred in 16.67% of the birds with an infection intensity of 3-24 mites/host. Infections in male and female hosts showed no significant differences. This study records for the first time R. rhinolethrum and its infection indices in N. peposaca in the southern of Brazil.


Assuntos
Anseriformes , Ácaros , Animais , Aves/parasitologia , Brasil , Patos , Feminino , Masculino
19.
Korean J Parasitol ; 59(5): 537-542, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34724776

RESUMO

This study intended to record a species of feather mite, Neopteronyssus bilineatus Mironov, 2003, (Arachnida: Pteronyssidae), from a grey-capped pygmy woodpecker, Yungipicus canicapillus (Blyth, 1845), in the Republic of Korea. Mite samples were collected from the flight feathers of a woodpecker, preserved directly in 95% ethyl alcohol, and then observed by a light microscope after specimen preparation. Morphology of Neopteronyssus bilineatus is distinguished from other pici group species by opisthosoma part with 2 longitudinal bends, tarsal seta rIII 3 times longer than tarsus III in males, and 2 elongated hysteronotal plates extending beyond the level of setae e2 in females. In the present study, a species of feather mite, N. bilineatus, was newly recorded from Y. canicapillus in Korean fauna.


Assuntos
Aves/parasitologia , Infestações por Ácaros , Ácaros , Animais , Feminino , Masculino , Microscopia , Infestações por Ácaros/veterinária , República da Coreia
20.
Proc Biol Sci ; 288(1961): 20211137, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34702076

RESUMO

Movement of the embryo is essential for musculoskeletal development in vertebrates, yet little is known about whether, and why, species vary. Avian brood parasites exhibit feats of strength in early life as adaptations to exploit the hosts that rear them. We hypothesized that an increase in embryonic movement could allow brood parasites to develop the required musculature for these demands. We measured embryo movement across incubation for multiple brood-parasitic and non-parasitic bird species. Using a phylogenetically controlled analysis, we found that brood parasites exhibited significantly increased muscular movement during incubation compared to non-parasites. This suggests that increased embryo movement may facilitate the development of the stronger musculoskeletal system required for the demanding tasks undertaken by young brood parasites.


Assuntos
Parasitos , Adaptação Fisiológica , Animais , Evolução Biológica , Aves/parasitologia , Interações Hospedeiro-Parasita , Comportamento de Nidação , Reprodução
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