FREQUENCY OF AVIAN HAEMOSPORIDIAN PARASITES IN BIRDS FROM MARGARITA AND COCHE ISLANDS, VENEZUELA

By amplifying and sequencing a mitochondrial DNA barcode (cytb), we screened the frequency of haemosporidian parasites (Haemoproteus, Plasmodium, Leucocytozoon) in 366 birds (23 species) from Margarita and Coche islands, Venezuela. In Coche (N = 24), none of the birds were infected, while in Margarita (N = 342) 13 individuals were (3.8%). The frequency of these parasites in endemic bird subspecies was more than double than in non-endemic forms (endemics = 7.3% vs non-endemic = 3.1%, N = 342), but it was not statistically significant. We found eight parasite lineages, four of which are novel (COLPAS09, COLSQU03, COLSQU04, HYPRUF01). COLSQU03, recorded in a dove (Columbina squammata), falls within the Haemoproteus (Parahaemoproteus) subgenus. This was unexpected because a strong signal of co-speciation has been found between Columbidae and the Haemoproteus (Haemoproteus) subgenus, suggesting a host-switching event

Can the intake of antiparasitic secondary metabolites explain the low prevalence of hemoparasites among wild Psittaciformes?

Background: Parasites can exert selection pressure on their hosts through effects on survival, on reproductive success, on sexually selected ornament, with important ecological and evolutionary consequences, such as changes in population viability. Consequently, hemoparasites have become the focus of recent avian studies. Infection varies significantly among taxa. Various factors might explain the differences in infection among taxa, including habitat, climate, host density, the presence of vectors, life history and immune defence. Feeding behaviour can also be relevant both through increased exposure to vectors and consumption of secondary metabolites with preventative or therapeutic effects that can reduce parasite load. However, the latter has been little investigated. Psittaciformes (parrots and cockatoos) are a good model to investigate these topics, as they are known to use biological control against ectoparasites and to feed on toxic food. We investigated the presence of avian malaria parasites (Plasmodium), intracellular haemosporidians (Haemoproteus, Leucocytozoon), unicellular flagellate protozoans (Trypanosoma) and microfilariae in 19 Psittaciformes species from a range of habitats in the Indo-Malayan, Australasian and Neotropical regions. We gathered additional data on hemoparasites in wild Psittaciformes from the literature. We considered factors that may control the presence of hemoparasites in the Psittaciformes, compiling information on diet, habitat, and climate. Furthermore, we investigated the role of diet in providing antiparasitic secondary metabolites that could be used as self-medication to reduce parasite load. Results: We found hemoparasites in only two of 19 species sampled. Among them, all species that consume at least one food item known for its secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, were free from hemoparasites. In contrast, the infected parrots do not consume food items with antimalarial or even general antiparasitic properties. We found that the two infected species in this study consumed omnivorous diets. When we combined our data with data from studies previously investigating blood parasites in wild parrots, the positive relationship between omnivorous diets and hemoparasite infestation was confirmed. Individuals from open habitats were less infected than those from forests. Conclusions: The consumption of food items known for their secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, as well as the higher proportion of infected species among omnivorous parrots, could explain the low prevalence of hemoparasites reported in many vertebrates

Mitochondrial DNA suggests multiple colonizations of central Philippine islands (Boracay, Negros) by the sedentary Philippine bulbul Hypsipetes philippinus guimarasensis (Aves)

In this study, we have used fragments of three mitochondrial genes (Control Region, CR; transfer RNA for methionine, tRNA-Met; NADH dehydrogenase subunit 2, ND2 for a total of 1066 bp) to reconstruct the phylogeographic history of the endemic Philippine bulbul (Hypsipetes philippinus) at the scale of the central area of the Philippine archipelago. The study includes two of the five recognized subspecies (guimarasensis and mindorensis), 7 populations and 58 individuals. Multiple phylogenetic and network analyses support the existence of two reciprocally monophyletic maternal lineages corresponding to the two named subspecies. Molecular clock estimates indicate that the split between the two subspecies is consistent with the Pleistocene geological history of the archipelago. Patterns of relationships within guimarasensis are biogeographically less clear. Here, a combination of vicariance and dispersal needs to be invoked to reconcile the molecular data with the geographical origin of samples. In particular, the two islands Boracay and Negros host mitochondrial lineages that do not form monophyletic clusters. Our genetic data suggest multiple independent colonization events for these locations

Prevalence of avian haemosporidian parasites and their host fidelity in the central Philippine islands

We examined the prevalence and host fidelity of avian haemosporidian parasites belonging to the genera Haemoproteus, Leucocytozoon and Plasmodium in the central Philippine islands by sampling 23 bird families (42 species). Using species-specific PCR assays of the mitochondrial cytochrome b gene (471 base pairs, bp), we detected infections in 91 of the 215 screened individuals (42%). We also discriminated between single and multiple infections. Thirty-one infected individuals harbored a single Haemoproteus lineage (14%), 18 a single Leucocytozoon lineage (8%) and 12 a single Plasmodium lineage (6%). Of the 215 screened birds, 30 (14%) presented different types of multiple infections. Intrageneric mixed infections were generally more common (18 Haemoproteus/Haemoproteus, 3 Leucocytozoon/Leucocytozoon, and 1 Plasmodium/Plasmodium) than intergeneric mixed infections (7 Haemoproteus/Leucocytozoon and 1 Haemoproteus/Leucocytozoon/Plasmodium). We recovered 81 unique haemosporidian mitochondrial haplotypes. These clustered in three strongly supported monophyletic clades that correspond to the three haemosporidian genera. Related lineages of Haemoproteus and Leucocytozoon were more likely to derive from the same host family than predicted by chance; however, this was not the case for Plasmodium. These results indicate that switches between host families are more likely to occur in Plasmodium. We conclude that Haemoproteus has undergone a recent diversification across well-supported host-family specific clades, while Leucocytozoon shows a longer association with its host(s). This study supports previous evidence of a higher prevalence and stronger host-family specificity of Haemoproteus and Leucocytozoon compared to Plasmodium. (C) 2012 Elsevier Ireland Ltd. All rights reserved

Profound population structure in the Philippine Bulbul Hypsipetes philippinus (Pycnonotidae, Aves) is not reflected in its Haemoproteus haemosporidian parasite

In this study we used molecular markers to screen for the occurrence and prevalence of the three most common haemosporidian genera (Haemoproteus, Plasmodium, and Leucocytozoon) in blood samples of the Philippine Bulbul (Hypsipetes philippinus), a thrush-size passerine bird endemic to the Philippine Archipelago. We then used molecular data to ask whether the phylogeographic patterns in this insular host-parasite system might follow similar evolutionary trajectories or not. We took advantage of a previous study describing the pattern of genetic structuring in the Philippine Bulbul across the Central Philippine Archipelago (6 islands, 7 populations and 58 individuals; three mitochondrial DNA genes). The very same birds were here screened for the occurrence of parasites by species-specific PCR assays of the mitochondrial cytochrome b gene (471 base pairs). Twenty-eight out of the 58 analysed birds had Haemoproteus (48%) infections while just 2% of the birds were infected with either Leucocytozoon or Plasmodium. Sixteen of the 28 birds carrying Haemoproteus had multiple infections. The phylogeography of the Philippine Bulbul mostly reflects the geographical origin of samples and it is consistent with the occurrence of two different subspecies on (1) Semirara and (2) Carabao, Boracay, North Gigante, Panay, and Negros, respectively. Haemoproteus phylogeography shows very little geographical structure, suggesting extensive gene flow among locations. While movements of birds among islands seem very sporadic, we found co-occurring evolutionary divergent parasite lineages. We conclude that historical processes have played a major role in shaping the host phylogeography, while they have left no signature in that of the parasites. Here ongoing population processes, possibly multiple reinvasions mediated by other hosts, are predominant. (C) 2011 Elsevier B.V. All rights reserved

Parasitological and serological evaluation of hemotropic infections in white-tailed deers (Odocoileus virginianus) in Venezuela

El objetivo de este trabajo fue evaluar parasitológica y serológicamente la presencia de Anaplasma spp., Trypanosoma spp. y Babesia spp. en venados de cola blanca (Odocoileus virginianus) en una región del Edo. Apure, en la cual coexisten con bovinos (Bos taurus), equinos (Equus caballus) y chigüires (Hydrochoerus hydrochaeris) infectados con estos hemoparásitos. Para ello se capturaron cinco venados de cola blanca en el hato El Cedral y se determinó la infección por estos patógenos mediante frotis de sangre y por ensayos serológicos, empleando la prueba de inmunofluorescencia e inmunoblot (Western Blot) en la cual se utilizaron como antígenos, extracto soluble de Trypanosoma evansi y la proteína recombinante mayor de superficie MSP5 de Anaplasma margínale. Mediante observación de frotis sanguíneo, dos venados resultaron positivos a A. marginale y ninguno a Trypanosoma spp. o Babesia spp. Por otro lado, un venado resultó positivo serológicamente a A. marginale y dos a T. evansi. Estos resultados sugieren que Odocoileus virginianus podría estar participando en el ciclo natural de la rickettisa A. marginale y de T. evansi, en conjunto con otros hospedadores como Bos taurus, Equus caballus y Hydrochoerus hydrochaeris de esta región de Venezuela.37 - [email protected] objective of this research was the parasitology and serology evaluation of the presence of Anaplasma spp., Trypanosoma spp. y Babesia spp in white tail dear (Odocoileus virginianus) in a region of Apure State in which them coexist with infected bovines (Bos taurus), horses (Equus caballus) and capybaras (Hydrochoerus hydrochaeris). For that, five whitetailed deer were captured in the Cedral Ranch, and the infection by these parasites where explored through blood smear and serological assays by inmunofluorescen and inmunoblot (Western Blot) using as antigens the soluble sonicated of Trypanosoma evansi and the recombinant Mayor Surface Protein (MSP5) of Anaplasma marginale. Two deers were detected positive for Anaplasma marginale by stained blood smear and no positives for Trypanosoma spp. or Babesia spp. One deer was seropositive for A. marginale and two were seropositive for Trypanosoma evansi. The above results suggest that the Odocoileus virginianus could be participating in the natural hemotropic cycle of A. marginale and T. evansi, together with the extensive production of Bos taurus, Equus caballus and Hydrochoerus hydrochaeris in this region of Venezuela

Additional file 1: of Can the intake of antiparasitic secondary metabolites explain the low prevalence of hemoparasites among wild Psittaciformes?

Table S1. Hemoparasites in wild Psittaciformes. Malaria parasites (Plasmodium), related intracellular haemosporidians (Haemoproteus and Leucocytozoon), the unicellular parasitic flagellate protozoans (Trypanosoma), and microfilaria reported in wild populations of Psittaciformes. The probability of detection for adults is based on a simulation (see Additional file 4) of the probability that the parasites will actually be detected given the sample size and an expected true prevalence based on the prevalences observed in wild Psittaciformes. The habitat and climate classification follow the references in Table 1. (XLSX 34 kb

Additional file 2: of Can the intake of antiparasitic secondary metabolites explain the low prevalence of hemoparasites among wild Psittaciformes?

Figure S1. Locations of the sampled population at Rasa I., Palawan, Philippines, in the Indo-Malayan zoogeographical region. Figure S2. Locations of the sampled populations in New Caledonia, Australasian zoogeographical region. Figure S3. Locations of the sampled population in the Chatham Is., Australasian zoogeographical region. Figure S4. Locations of the sampled populations in New Zealand, Australasian zoogeographical region. Figure S5. Locations of the sampled populations in the Neotropical zoogeographical region. (PDF 1271 kb