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1.
Acta Trop ; 257: 107286, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38876165

ABSTRACT

Forest regeneration is becoming a powerful tool to combat land conversion which covers 30 % of the Neotropical territory. However, little is known about the effect of forest regeneration on vector-borne diseases. Here, we describe the haemosporidian lineage composition across a successional gradient within an Atlantic Forest bird community. We test whether forest successional stages, in addition to host life history traits affect haemosporidian infection probability. We sampled birds at 16 sampling units with different successional stages between 2017 and 2018 within a forest remnant located in Antonina, Paraná, Brazil. We captured bird individuals using mist-nets, identified them to the species level, and collected blood samples to detect and identify Plasmodium and Haemoproteus lineages based on molecular analysis. We used a Bayesian phylogenetic linear model with a Bernoulli distribution to test whether the haemosporidian infection probability is affected by nest type, foraging stratum, and forest successional stage. We captured 322 bird individuals belonging to 52 species and 21 families. We found 31 parasite lineages and an overall haemosporidian prevalence of 23.9 %, with most infections being caused by Plasmodium (21.7 % of prevalence). The Plasmodium probability of infection was associated with forest successional stage and bird foraging stratum. Birds from the secondary forest in an intermediate stage of succession are more likely to be infected by the parasites than birds from the primary forests (ß = 1.21, 95 % CI = 0.11 - 2.43), birds from upper strata exhibit a lower probability of infection than birds from lower foraging strata (ß = -1.81, 95 % CI = -3.80 - -0.08). Nest type did not affect the Plasmodium probability of infection. Our results highlight the relevance of forest succession on haemosporidian infection dynamics, which is particularly relevant in a world where natural regeneration is the main tool used in forest restoration.


Subject(s)
Bird Diseases , Birds , Forests , Haemosporida , Animals , Birds/parasitology , Haemosporida/isolation & purification , Haemosporida/genetics , Brazil/epidemiology , Prevalence , Bird Diseases/parasitology , Bird Diseases/epidemiology , Plasmodium/isolation & purification , Plasmodium/classification , Phylogeny , Protozoan Infections, Animal/epidemiology , Protozoan Infections, Animal/parasitology , Bayes Theorem
2.
Parasitol Res ; 123(6): 252, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38922536

ABSTRACT

Avian haemosporidians of the genera Plasmodium and Haemoproteus are a group of widely distributed blood parasites that can negatively affect the fitness of their hosts. Colombia contains the greatest diversity of birds on the planet, but knowledge about the associations between haemosporidian and its avifauna is scarce and fragmented. We collected blood samples from 255 birds (203 residents and 52 neotropical migrants) belonging to 27 families and 108 species. The study was conducted in six localities in the inter-Andean valleys of the Cauca and Magdalena rivers. Parasites of the genera Plasmodium and Haemoproteus were identified in the samples by morphological and molecular analysis of a fragment of the mitochondrial gene cyt b. Among the samples, 9.3% (n = 24) were positive for Plasmodium or Haemoproteus. Co-infection with Plasmodium and Haemoproteus was found in Red-eyed Vireo. Seventeen haemosporidian lineages were identified, five of which were reported for the first time in resident birds (Common Ground Dove, Checker-throated Stipplethroat, Tropical Kingbird, Pale-breasted Thrush, and Ruddy-breasted Seedeater) and one in the Summer Tanager (neotropical migrant). The research results confirm the wide diversity of haemosporidian present in tropical lowlands and the possible role of neotropical migratory birds in dissemination on haemosporidian along their migratory routes.


Subject(s)
Bird Diseases , Birds , Haemosporida , Plasmodium , Protozoan Infections, Animal , Animals , Colombia/epidemiology , Haemosporida/classification , Haemosporida/isolation & purification , Haemosporida/genetics , Birds/parasitology , Bird Diseases/parasitology , Bird Diseases/epidemiology , Plasmodium/classification , Plasmodium/isolation & purification , Plasmodium/genetics , Protozoan Infections, Animal/parasitology , Protozoan Infections, Animal/epidemiology , Cytochromes b/genetics , Animal Migration , Phylogeny , Coinfection/parasitology , Coinfection/veterinary , Coinfection/epidemiology
3.
Proc Biol Sci ; 291(2018): 20232705, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38444334

ABSTRACT

The correct identification of variables affecting parasite diversity and assemblage composition at different spatial scales is crucial for understanding how pathogen distribution responds to anthropogenic disturbance and climate change. Here, we used a database of avian haemosporidian parasites to test how the taxonomic and phylogenetic diversity and phylogenetic structure of the genera Plasmodium, Haemoproteus and Leucocytozoon from three zoogeographic regions are related to surrogate variables of Earth's energy input, habitat heterogeneity (climatic diversity, landscape heterogeneity, host richness and human disturbance) and ecological interactions (resource use), which was measured by a novel assemblage-level metric related to parasite niche overlap (degree of generalism). We found that different components of energy input explained variation in richness for each genus. We found that human disturbance influences the phylogenetic structure of Haemoproteus while the degree of generalism explained richness and phylogenetic structure of Plasmodium and Leucocytozoon genera. Furthermore, landscape attributes related to human disturbance (human footprint) can filter Haemoproteus assemblages by their phylogenetic relatedness. Finally, assembly processes related to resource use within parasite assemblages modify species richness and phylogenetic structure of Plasmodium and Leucocytozoon assemblages. Overall, our study highlighted the genus-specific patterns with the different components of Earth's energy budget, human disturbances and degree of generalism.


Subject(s)
Haemosporida , Host Specificity , Humans , Animals , Phylogeny , Anthropogenic Effects , Birds
4.
Parasitol Res ; 122(9): 2065-2077, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37391644

ABSTRACT

The Brazilian Amazon supports an extremely diverse avifauna and serves as the diversification center for avian malaria parasites in South America. Construction of hydroelectric dams can drive biodiversity loss by creating islands incapable of sustaining the bird communities found in intact forest sites. Besides anthropogenic actions, the presence of parasites can also influence the dynamics and structure of bird communities. Avian malaria (Plasmodium) and related haemosporidian parasites (Haemoproteus and Leucocytozoon) are a globally distributed group of protozoan parasites recovered from all major bird groups. However, no study to date has analyzed the presence of avian haemosporidian parasites in fragmented areas such as land bridge islands formed during artificial flooding following the construction of hydroelectric dams. The aim of this study is to assess the prevalence and molecular diversity of haemosporidians in bird communities inhabiting artificial islands in the area of the Balbina Hydroelectric Dam. The reservoir area covers 443,700 ha with 3546 islands on the left bank of the Uatumã River known to contain more than 400 bird species. We surveyed haemosporidian infections in blood samples collected from 445 understory birds, belonging to 53 species, 24 families, and 8 orders. Passeriformes represented 95.5% of all analyzed samples. We found a low overall Plasmodium prevalence (2.9%), with 13 positive samples (two Plasmodium elongatum and 11 Plasmodium sp.) belonging to eight lineages. Six of these lineages were previously recorded in the Amazon, whereas two of them are new. Hypocnemis cantator, the Guianan Warbling Antbird, represented 38.5% of all infected individuals, even though it represents only 5.6% of the sampled individuals. Since comparison with Plasmodium prevalence data prior to construction of Balbina is not possible, other studies in artificially flooded areas are imperative to test if anthropogenic flooding may disrupt vector-parasite relationships leading to low Plasmodium prevalence.


Subject(s)
Bird Diseases , Haemosporida , Malaria, Avian , Parasites , Passeriformes , Plasmodium , Humans , Animals , Parasites/genetics , Malaria, Avian/parasitology , Islands , Brazil/epidemiology , Prevalence , Bird Diseases/epidemiology , Bird Diseases/parasitology , Plasmodium/genetics , Haemosporida/genetics , Genetic Variation
5.
Parasitology ; 150(14): 1277-1285, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37246557

ABSTRACT

The relationships between host phylogenetics, functional traits and parasites in wildlife remain poorly understood in the Neotropics, especially in habitats with marked seasonal variation. Here, we examined the effect of seasonality and host functional traits on the prevalence of avian haemosporidians (Plasmodium and Haemoproteus) in the Brazilian Caatinga, a seasonally dry tropical forest. 933 birds were evaluated for haemosporidian infections. We found a high parasitism prevalence (51.2%), which was correlated with phylogenetic relatedness among avian species. Prevalence varied drastically among the 20 well-sampled species, ranging from 0 to 70%. Seasonality was the main factor associated with infections, but how this abiotic condition influenced parasite prevalence varied according to the host-parasite system. Plasmodium prevalence increased during the rainy season and, after excluding the large sample size of Columbiformes (n = 462/933), Plasmodium infection rate was maintained high in the wet season and showed a negative association with host body mass. No association was found between non-Columbiform bird prevalence and seasonality or body mass when evaluating both Plasmodium and Haemoproteus or only Haemoproteus infections. Parasite community was composed of 32 lineages including 7 new lineages. We evidenced that even dry domains can harbour a high prevalence and diversity of vector-borne parasites and pointed out seasonality as a ruling factor.


Subject(s)
Bird Diseases , Haemosporida , Parasites , Plasmodium , Protozoan Infections, Animal , Animals , Phylogeny , Prevalence , Brazil/epidemiology , Plasmodium/genetics , Birds/parasitology , Haemosporida/genetics , Forests , Bird Diseases/epidemiology , Bird Diseases/parasitology , Protozoan Infections, Animal/epidemiology , Protozoan Infections, Animal/parasitology
6.
Biosci. j. (Online) ; 39: e39071, 2023.
Article in English | LILACS-Express | LILACS | ID: biblio-1566087

ABSTRACT

Haemosporidian parasites can cause pathogenic infections, leading to death or a reduction in the physical and reproductive abilities of the host. Several studies have identified haemosporidian infections in neotropical bird communities, but few have been conducted in populations, relating the infection to the biological attributes of the species. To determine haemosporidian prevalence in a population of Antilophia galeata and to assess factors that may be associated with parasitaemia, we analysed blood smears of 62 individuals from a Cerrado forest fragment. For each individual, the body mass, length of tarsus, sex, presence/absence of brood patch and feather moult were recorded. In total, 33 (53.2%) individuals were infected with haemosporidian parasites, 32 (51.6%) were infected with Plasmodium spp. and one (1.61%) was infected with Haemoproteus sp. Parasitaemia was not related to seasons, sex, reproduction, moulting or body condition but correlated positively with total leucocyte count, suggesting that individuals may be effective in infection control. This population may be tolerant to haemosporidian parasites because, despite the high prevalence, parasitaemia was low and constant; this is a potentially chronic infection that showed no adverse effects on the parameters analysed in this population.

7.
Parasitology ; : 1-14, 2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36345570

ABSTRACT

Haemosporidian genera Plasmodium, Haemoproteus and Leucocytozoon, responsible for avian malarial infections, are highly diverse and have a wide range of health effects and predictors, depending on the host and its environmental context. Here, we present, for the first time, detailed information on the identity, prevalence and parasitaemia of haemosporidians and other haemoparasites that infect the ash-breasted Sierra finch, Geospizopsis plebejus, in an Andean dry forest. We study the consequences of infection in the host body and health conditions and explore the environmental and intrinsic factors that influence infection status and parasitaemia. We conducted diagnoses by cytochrome b (cytb) sequencing and morphological identification, and estimated the levels of parasitaemia based on microscopy. We identified 6 cytb lineages infecting G. plebejus. Two of them were new lineages: Haemoproteus sp. GEPLE01 and GEPLE02. We also detected Haemoproteus sp. ZOCAP08, Haemoproteus sp. AMAVIR01, Plasmodium homopolare BAEBIC02 and Plasmodium cathemerium ZONCAP15. By microscopy, we detected Haemoproteus coatneyi, Haemoproteus erythrogravidus, P. homopolare and other unidentified species of Haemoproteus, Plasmodium, Babesia sp. and 1 microfilaria. We found no evidence of Leucocytozoon. Additionally, we detected several coinfections by sequencing and microscopy. The prevalence of haemosporidian infections was high (87.7%), and the mean parasitaemia was 61.65 infected cells per 10 000 erythrocytes examined. Prevalence and parasitaemia were higher for Haemoproteus than for Plasmodium. Haemoproteus sp. AMAVIR01 showed the highest prevalence (43.1%) and mean parasitaemia (94.39/10 000 erythrocytes) and might be associated with H. coatneyi. Immature individuals showed a lower prevalence than adults, supporting previous findings.

9.
Parasitology ; 149(13): 1760-1768, 2022 11.
Article in English | MEDLINE | ID: mdl-36165282

ABSTRACT

Migratory birds are implicated in dispersing haemosporidian parasites over great geographic distances. However, their role in sharing these vector-transmitted blood parasites with resident avian host species along their migration flyway is not well understood. We studied avian haemosporidian parasites in 10 localities where Chilean Elaenia, a long-distance Neotropical austral migrant species, spends part of its annual cycle to determine local parasite transmission among resident sympatric host species in the elaenia's distributional range across South America. We sampled 371 Chilean Elaenias and 1,818 birds representing 243 additional sympatric species from Brazilian wintering grounds to Argentinian breeding grounds. The 23 haemosporidian lineages found in Chilean Elaenias exhibited considerable variation in distribution, specialization, and turnover across the 10 avian communities in South America. Parasite lineage dissimilarity increased with geographic distance, and infection probability by Parahaemoproteus decreased in localities harbouring a more diverse haemosporidian fauna. Furthermore, blood smears from migrating Chilean Elaenias and local resident avian host species did not contain infective stages of Leucocytozoon, suggesting that transmission did not take place in the Brazilian stopover site. Our analyses confirm that this Neotropical austral migrant connects avian host communities and transports haemosporidian parasites along its distributional range in South America. However, the lack of transmissive stages at stopover site and the infrequent parasite lineage sharing between migratory host populations and residents at breeding and wintering grounds suggest that Chilean Elaenias do not play a significant role in dispersing haemosporidian parasites, nor do they influence local transmission across South America.


Subject(s)
Bird Diseases , Haemosporida , Parasites , Passeriformes , Plasmodium , Animals , Prevalence , Chile/epidemiology , Bird Diseases/epidemiology , Bird Diseases/parasitology , Haemosporida/genetics , Phylogeny
10.
Parasitology ; 149(8): 1129-1144, 2022 07.
Article in English | MEDLINE | ID: mdl-35535473

ABSTRACT

Long-term, inter-annual and seasonal variation in temperature and precipitation influence the distribution and prevalence of intraerythrocytic haemosporidian parasites. We characterized the climatic niche behind the prevalence of the three main haemosporidian genera (Haemoproteus, Plasmodium and Leucocytozoon) in central-eastern Mexico, to understand their main climate drivers. Then, we projected the influence of climate change over prevalence distribution in the region. Using the MaxEnt modelling algorithm, we assessed the relative contribution of bioclimatic predictor variables to identify those most influential to haemosporidian prevalence in different avian communities within the region. Two contrasting climate change scenarios for 2070 were used to create distribution models to explain spatial turnover in prevalence caused by climate change. We assigned our study sites into polygonal operational climatic units (OCUs) and used the general haemosporidian prevalence for each OCU to indirectly measure environmental suitability for these parasites. A high statistical association between global prevalence and the bioclimatic variables 'mean diurnal temperature range' and 'annual temperature range' was found. Climate change projections for 2070 showed a significant modification of the current distribution of suitable climate areas for haemosporidians in the study region.


Subject(s)
Bird Diseases , Haemosporida , Parasites , Plasmodium , Animals , Bird Diseases/epidemiology , Bird Diseases/parasitology , Climate Change , Mexico/epidemiology , Phylogeny , Prevalence
11.
PeerJ ; 10: e13485, 2022.
Article in English | MEDLINE | ID: mdl-35611171

ABSTRACT

South America has different biomes with a high richness of wild bird species and Diptera vectors, representing an ideal place to study the influence of habitat on vector-borne parasites. In order to better understand how different types of habitats do or do not influence the prevalence of haemosporidians, we performed a new analysis of two published datasets comprising wild birds from the Brazilian Savanna (Cerrado) as well as wild birds from the Venezuelan Arid Zone. We investigated the prevalence and genetic diversity of haemosporidian parasites belonging to two genera: Plasmodium and Haemoproteus. We evaluated data from 676 wild birds from the Cerrado and observed an overall prevalence of 49%, whereas, in the Venezuelan Arid Zone, we analyzed data from 527 birds and found a similar overall prevalence of 43%. We recovered 44 lineages, finding Plasmodium parasites more prevalent in the Cerrado (15 Plasmodium and 12 Haemoproteus lineages) and Haemoproteus in the Venezuelan Arid Zone (seven Plasmodium and 10 Haemoproteus lineages). No difference was observed on parasite richness between the two biomes. We observed seven out of 44 haemosporidian lineages that are shared between these two distinct South American biomes. This pattern of parasite composition and prevalence may be a consequence of multiple factors, such as host diversity and particular environmental conditions, especially precipitation that modulate the vector's dynamics. The relationship of blood parasites with the community of hosts in large and distinct ecosystems can provide more information about what factors are responsible for the variation in the prevalence and diversity of these parasites in an environment.


Subject(s)
Bird Diseases , Haemosporida , Malaria , Parasites , Plasmodium , Animals , Parasites/genetics , Ecosystem , Prevalence , Bird Diseases/epidemiology , Plasmodium/genetics , Haemosporida/genetics , Malaria/epidemiology , Brazil/epidemiology , Birds/parasitology
12.
Parasitol Res ; 121(6): 1775-1787, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35435509

ABSTRACT

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.


Subject(s)
Bird Diseases , Haemosporida , Parasites , Plasmodium , Protozoan Infections, Animal , Animals , Animals, Wild , Bird Diseases/epidemiology , Bird Diseases/parasitology , Birds/parasitology , Colombia/epidemiology , Ecosystem , Haemosporida/genetics , Humans , Phylogeny , Plasmodium/genetics , Prevalence , Protozoan Infections, Animal/epidemiology , Protozoan Infections, Animal/parasitology
13.
Curr Zool ; 68(1): 27-40, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35169627

ABSTRACT

Characterizing the diversity and structure of host-parasite communities is crucial to understanding their eco-evolutionary dynamics. Malaria and related haemosporidian parasites are responsible for fitness loss and mortality in bird species worldwide. However, despite exhibiting the greatest ornithological biodiversity, avian haemosporidians from Neotropical regions are quite unexplored. Here, we analyze the genetic diversity of bird haemosporidian parasites (Plasmodium and Haemoproteus) in 1,336 individuals belonging to 206 bird species to explore for differences in diversity of parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions. We detected 70 different haemosporidian lineages infecting 74 bird species. We showed that 25 out of the 70 haplotypes had not been previously recorded. Moreover, we also identified 81 new host-parasite interactions representing new host records for these haemosporidian parasites. Our outcomes revealed that the effective diversity (as well as the richness, abundance, and Shannon-Weaver index) for both birds and parasite lineages was higher in Amazon basin ecoregions. Furthermore, we also showed that ecoregions with greater diversity of bird species also had high parasite richness, hence suggesting that host community is crucial in explaining parasite richness. Generalist parasites were found in ecoregions with lower bird diversity, implying that the abundance and richness of hosts may shape the exploitation strategy followed by haemosporidian parasites. These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidian lineages. Further studies analyzing host distribution and specificity of these parasites in the tropics will provide important knowledge about phylogenetic relationships, phylogeography, and patterns of evolution and distribution of haemosporidian parasites.

14.
Parasitol Res ; 121(5): 1407-1417, 2022 May.
Article in English | MEDLINE | ID: mdl-35106653

ABSTRACT

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.


Subject(s)
Bird Diseases , Haemosporida , Parasites , Plasmodium , Protozoan Infections, Animal , Animals , Bird Diseases/epidemiology , Bird Diseases/parasitology , Birds/parasitology , Phylogeny , Plasmodium/genetics , Prevalence , Protozoan Infections, Animal/epidemiology
15.
PeerJ ; 9: e11555, 2021.
Article in English | MEDLINE | ID: mdl-34221715

ABSTRACT

Avian haemosporidians are parasites with great capacity to spread to new environments and new hosts, being considered a good model to host-parasite interactions studies. Here, we examine avian haemosporidian parasites in a protected area covered by Restinga vegetation in northeastern Brazil, to test the hypothesis that haemosporidian prevalence is related to individual-level traits (age and breeding season), species-specific traits (diet, foraging strata, period of activity, species body weight, migratory status, and nest shape), and climate factors (temperature and rainfall). We screened DNA from 1,466 birds of 70 species captured monthly from April 2013 to March 2015. We detected an overall prevalence (Plasmodium/Haemoproteus infection) of 22% (44 host species) and parasite's lineages were identified by mitochondrial cyt b gene. Our results showed that migration can be an important factor predicting the prevalence of Haemoproteus (Parahaemoproteus), but not Plasmodium, in hosts. Besides, the temperature, but not rainfall, seems to predict the prevalence of Plasmodium in this bird community. Neither individual-level traits analyzed nor the other species-specific traits tested were related to the probability of a bird becoming infected by haemosporidians. Our results point the importance of conducting local studies in particular environments to understand the degree of generality of factors impacting parasite prevalence in bird communities. Despite our attempts to find patterns of infection in this bird community, we should be aware that an avian haemosporidian community organization is highly complex and this complexity can be attributed to an intricate net of factors, some of which were not observed in this study and should be evaluated in future studies. We evidence the importance of looking to host-parasite relationships in a more close scale, to assure that some effects may not be obfuscated by differences in host life-history.

16.
Vet World ; 14(4): 889-896, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34083937

ABSTRACT

BACKGROUND AND AIM: Avian malaria is a tropical disease caused by protozoans of the genera Plasmodium and Haemoproteus. As a nonlethal disease, avian malaria can affect the lifespan and reproductive rate of birds. If there is a differential effect depending on bird species, then this disease might have a significant effect on avian biodiversity. The current study aimed to determine the incidence of Plasmodium in hummingbirds in humid premontane forest areas. MATERIALS AND METHODS: Blood samples (n=60) were collected from hummingbirds from two areas (Santuario de Aves Milpe and Hacienda Puyucunapi) of Pichincha Province, Ecuador. Prevalence and parasitemia were determined by microscopic examination of blood smears stained with Giemsa reagent. Both study sites are part of a 1000 m elevational gradient; hence, elevation was used as a predictor variable for prevalence and parasitemia levels in a Mann-Whitney U-test. This test was also used to test for a sex bias. RESULTS: This study reports on a total of 12 bird species that inhabit both study sites. At Milpe, the lower elevation site, a prevalence of 100% was recorded, whereas at Puyucunapi, the prevalence was 96%. The combined prevalence was 97%. Elevation and sex did not influence prevalence nor parasitemia in hummingbirds. CONCLUSION: This study does not suggest a significant elevation or sex bias on prevalence and parasitemia in hummingbirds.

17.
Int J Parasitol ; 51(11): 899-911, 2021 10.
Article in English | MEDLINE | ID: mdl-34044005

ABSTRACT

The specialist versus generalist strategies of hemoparasites in relation to their avian host, as well as environmental factors, can influence their prevalence, diversity and distribution. In this paper we investigated the influence of avian host species, as well as the environmental and geographical factors, on the strategies of Haemoproteus and Plasmodium hemoparasites. We determined prevalence and diversity by targeting their cytochrome b (Cytb) in a total of 2,590 passerine samples from 138 localities of Central and South America, and analysed biogeographic patterns and host-parasite relationships. We found a total prevalence of 23.2%. Haemoproteus presented a higher prevalence (15.3%) than Plasmodium (4.3%), as well as a higher diversity and host specificity. We determined that Plasmodium and Haemoproteus prevalences correlated positively with host diversity (Shannon index) and were significantly influenced by bird diversity, demonstrating a possible "amplification effect". We found an effect of locality and the avian family for prevalences of Haemoproteus and Plasmodium. These results suggest that Haemoproteus is more specialist than Plasmodium and could be mostly influenced by its avian host and the Andes Mountains.


Subject(s)
Bird Diseases , Haemosporida , Malaria, Avian , Parasites , Plasmodium , Protozoan Infections, Animal , Animals , Bird Diseases/epidemiology , Haemosporida/genetics , Malaria, Avian/epidemiology , Phylogeny , Plasmodium/genetics , Prevalence
18.
Vet Parasitol Reg Stud Reports ; 23: 100521, 2021 01.
Article in English | MEDLINE | ID: mdl-33678376

ABSTRACT

The order Haemosporida is widely distributed parasitizing members of the Aves class. In birds of prey, infection with Plasmodium spp. parasites varies from an apathogenic form to a clinical syndrome. However, studies on Haemosporida in raptors from the neotropical region are scarce. The aim of this study was to investigate natural infection by Plasmodium spp., Haemoproteus spp. and Leucocytozoon spp. in free-ranging wild raptors from southern Brazil. For this, we sampled 206 individuals of 21 species: 94 live-trapped Southern Caracaras (Caracara plancus) and 112 raptors from other species that were brought to rehabilitation centers. The presence of infection was investigated using a nested-PCR for Haemosporida performed on blood samples. Overall, 56 out of 206 birds were positive for Plasmodium spp./Haemoproteus spp. Twenty-two percent (21/94) of the C. plancus samples were positive. Of the 112 wild raptors rescued, 31% (35/112) of those belonging to 15 other species tested positive. No sample was positive for Leucocytozoon spp. Herein, we demonstrated nine lineages of Haemosporidian parasites (eight Plasmodium sp. and one Haemoproteus sp.) in free-living species of Brazilian birds of prey, being six of them potential novel lineages. It suggests that information currently available on South-American haemosporidian from these birds greatly underestimate the potential lineage diversity in this region.


Subject(s)
Haemosporida , Phylogeny , Raptors , Animals , Brazil/epidemiology , Haemosporida/classification , Raptors/parasitology
19.
Pathogens ; 10(2)2021 Jan 21.
Article in English | MEDLINE | ID: mdl-33494428

ABSTRACT

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

20.
Parasitol Res ; 120(2): 605-613, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33415388

ABSTRACT

Studies contrasting parasite prevalence and host-parasite community structure between pristine and disturbed environments will improve our understanding of how deforestation affects disease transmission and parasite extinction. To determine how infection rates of a common and diverse group of avian blood parasites (Plasmodium and Haemoproteus) respond to changes in avian host composition after mining, we surveyed 25 bird communities from pristine forests (two forest types: plateau and hillside) and reforested sites in Northeast Amazonia. Infection rates and both parasite and avian host community structure exhibited considerable variation across the deforestation gradient. In opposition to the emerging pattern of lower avian haemosporidian prevalence in disturbed tropical forests in Africa, we show that secondary forests had higher haemosporidian prevalence in one of the largest mining areas of Amazonia. The dissimilarity displayed by bird communities may explain, in part, the higher prevalence of Haemoproteus in reforested areas owing to the tolerance of some bird species to open-canopy forest habitat. On the other hand, deforestation may cause local extinction of Plasmodium parasites due to the loss of their avian hosts that depend on closed-canopy primary forest habitats. Our results demonstrate that forest loss induced by anthropogenic changes can affect a host-parasite system and disturb both parasite transmission and diversity.


Subject(s)
Apicomplexa/isolation & purification , Bird Diseases/epidemiology , Host-Parasite Interactions , Animals , Apicomplexa/genetics , Biodiversity , Bird Diseases/parasitology , Bird Diseases/transmission , Birds , Brazil/epidemiology , DNA Barcoding, Taxonomic/veterinary , Ecosystem , Forests , Geography , Haemosporida/genetics , Haemosporida/isolation & purification , Mining , Plasmodium/genetics , Plasmodium/isolation & purification , Prevalence
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