Detection and molecular characterization of Trichomonas gallinae recovered from domestic pigeons in Egypt.

Trichomonas gallinae is a protozoan parasite that causes canker in pigeons. Squabs (young pigeons) are frequently infected with T. gallinae and can die because of the infection, while adult pigeons can act as carriers showing no clinical signs. In the present study, 50 squabs, up to 1-month-old, were purchased from pigeon markets in different regions of the Giza governorate, Egypt. Direct wet mount preparations of the oral excretions of the squabs (mouth wash) and Giemsa staining revealed that 64% (32/50) were positive for T. gallinae. Experimental infection of ten squabs with 103 T. gallinae trophozoites/ml resulted in oral lesions on the mouth, tongue, and soft palate, with the presence of yellowish-white nodules (cheese-like) in the oral cavity on the sixth day post-infection in all squabs. A subset of five samples were cultured in modified Diamond's media, their DNA was extracted, and a portion of the ribosomal internal transcribed spacer region (ITS1/5.8S/ITS2) was amplified by polymerase chain reaction (PCR) followed by sequencing. Phylogenetic analysis of the five isolates revealed 64-91% homology with some reference isolates circulating in Egypt and related countries.

Three new species of Clinostomum Leidy, 1856 (Trematoda) from Middle American fish-eating birds.

We recently engaged in a two-part study of Clinostomum Leidy, 1856 across a geographic range comprising central Mexico southwards to Costa Rica, in Central America. In the first study, we investigated the species boundaries by using DNA sequences of mitochondrial and nuclear molecular markers, implementing several analytical tools and species delimitation methods. The result of that approach revealed five highly divergent genetic lineages that were interpreted as independent evolutionary units, or species. Here, we present the second part of the study, where we describe three of the five species for which we have sexually mature adult specimens obtained from the mouth cavity of fish-eating birds. Additionally, we characterise morphologically the metacercariae of the other two species, collected from freshwater fishes; these species cannot be formally described since no adults were found in their definitive hosts. We further discuss the characters that are more reliable for species identification within Clinostomum, such as the cirrus sac shape and relative position with respect to testes and ovary, the shape of the reproductive organs, and the diverticulated condition of the caeca.

DNA barcodes reveal female dimorphism in syringophilid mites (Actinotrichida: Prostigmata: Cheyletoidea): Stibarokris phoeniconaias and Ciconichenophilus phoeniconaias are conspecific.

Here we present the first evidence of female dimorphism in ectoparasitic quill mites of the family Syringophilidae (Actinotrichida: Prostigmata: Cheyletoidea). Stibarokris phoeniconaias Skoracki et OConnor, 2010 and Ciconichenophilus phoeniconaias Skoracki et OConnor, 2010 so far have been treated as two distinct species cohabiting inside the quills of feathers of the lesser flamingo Phoeniconaias minor (Geoffroy Saint-Hilaire) and the American flamingo Phoenicopterus ruber Linnaeus. Although females of these species differ morphologically by the extent of body sclerotisation, presence/absence of lateral hypostomal teeth, and shape of dorsal setae, their important common features are the lack of leg setae vs II, and both stylophore and peritremes shape. Here, we apply the DNA barcode markers to test whether the differences between S. phoeniconaias and C. phoeniconaias have a genetic basis, indicating that they really are distinct taxa, or whether they just represent two morphs of a single species. All analysed sequences (616 bp for COI and 1159 bp for 28S rDNA) obtained for specimens representing females of both studied taxa as well as male, tritonymph, protonymph and larva of S. phoeniconaias were identical, which indicates that S. phoeniconaias and C. phoeniconaias are conspecific. The formal taxonomic consequence of our results is denial of the genus status of Ciconichenophilus Skoracki et OConnor, 2010 and species status of C. phoeniconaias, and recommendation that they should be treated as junior synonyms of Stibarokris Kethley, 1970 and S. phoeniconaias, respectively.

INFLUENCE OF GROOMING ON PERMANENT ARTHROPOD ASSOCIATES OF BIRDS: CATTLE EGRETS, LICE, AND MITES.

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.

Finding a needle in a haystack: DNA Haemoproteus columbae enrichment using percoll density gradient and flow cytometry.

Isolation of genomic DNA of blood parasites in birds, reptiles, amphibians, and fishes is a challenging task, given that their red blood cells are nucleated; for that reason, parasite genomic DNA is only a fraction of the total extracted DNA, and it is challenging to obtain concentrated high-quality genetic material. Percoll Density Gradient (PDG) and flow cytometry are tools for separating and analyzing cell populations or even a single cell, and both represent potent approaches for isolating avian haemosporidians parasites. Our experimental design included several steps seeking to concentrate the parasite´s DNA. We used blood samples from a Rock pigeon infected with Haemoproteus columbae. After inducing parasite exflagellation and gametogenesis in vitro, we subjected the samples to a Percoll Density Gradient to separate the parasites from the rest of the blood cells. Following centrifugation, the layer containing extracellular parasites underwent a flow cytometry and cell sorting process, during which we selected two different subpopulations of cells for analysis. Based on qPCR analyses, we demonstrate parasite DNA enrichment in Percoll Density Gradient and flow cytometry samples; simultaneously, these samples showed the lowest concentration of Columba livia DNA. However, the concentration of parasite DNA was higher in the PDG than in the cell sorting sample. This study reports the concentration of the Haemoproteus parasite by flow cytometry without DNA-intercalating dyes, and this methodology can serve as a technique for DNA enrichment of blood parasites infecting nucleated red blood cells to improve techniques that allow obtaining complete genomes.

Trichomonosis in free-ranging Eurasian collared doves (Streptopelia decaocto) and African collared dove hybrids (Streptopelia risoria) in the Caribbean and description of ITS-1 region genotypes.

We report the first documented occurrence of an outbreak of trichomonosis in a free-ranging small flock of Eurasian collared doves (Streptopelia decaocto) and African collared dove hybrids (Streptopelia risoria) in the Caribbean. In total, 18 birds were examined, including six African collared dove x Eurasian collared dove hybrids and 12 Eurasian collared doves. The affected age class consisted of adults. Sex distribution was equal. With a flock population size of 200 birds, mortality rate for the outbreak was estimated at 15-20%. Living birds were weak, showing evidence of mucus-stained beaks and open-mouth breathing. Caseous ulcerative yellow lesions were restricted to the upper gastrointestinal tract, with the exception of one bird, which had lesions in the upper gastrointestinal tract and in the liver. Ninety-four percent (17/18) of the affected birds had multiple extensive lesions. Lesions located on the roof of the oral cavity extended in 33% (6/18) into the orbit and in 11% (2/18) into the braincase. Using wet-mount microscopy, we were able to confirm Trichomonas gallinae in 22% (4/18) of the sampled animals. Fifteen samples submitted for PCR analysis tested positive. Sequence analysis of the internal transcribed spacer 1 (ITS-1) region of the ribosomal RNA (rRNA) revealed two distinct genotypes of Trichomonas. One sequence had 100% identity to the prototype T. gallinae isolate, whereas the other sequences had 98-100% identity to recently described Trichomonas-like parabasalid. On the basis of gross and histologic findings, along with the sequence results from the columbids in this report, it is likely that this Trichomonas-like parabasalid is pathogenic.

Effects of a neem seed extract (MiteStop®) on mallophages (featherlings) of chicken: in vivo and in vitro studies.

Mallophages of birds (featherlings) are mostly very tiny and can even as adults better be recognized by their movements than by their elongate body shape when using just the naked eye. Since some species (e.g., the "shaft louse" Menopon gallinae, the elongate feather louse Lipeurus caponis, or Columbicola sp.) may pierce the pulp of feathers or the skin by their biting or scratching mandibles and thus lick the excreted blood, they may be extremely dangerous especially to young birds, even if they only feed by nibbling along the feather surface and/or eat epidermal debris. The present paper reports on the successful treatment of different races of fowls being severely infested with both above cited species. This in vivo treatment was done either by a short dipping of the whole fowl into the 1:33 dilution (with tap water) of a neem seed extract (MiteStop®) or by spraying them with the freshly diluted product. It was seen that the dead mallophages dropped down from the feathers as soon as they were dry again. As a precaution, a second treatment was done by some owners 1 week after the first one in order to eliminate all stages, which eventually might have hatched from untouched nits during the time interval between the two treatments. When controlling the treated fowls 4 weeks after the treatment, in no case (treated once or twice), living motile stages were diagnosed indicating the high efficacy of this nontoxic neem seed extract. When treating in vitro cutoff feathers contaminated with L. caponis, it was seen under the stereomicroscope, that the mallophages tried to run away from the 1:33 water-diluted active compound indicating that there is also a repellent effect. Treated L. caponis stopped leg movements within 3 min and died on their feathers within 1-20 min. Then, the last slight trembling movements of their legs and convulsions of their intestine stopped finally.

Biodiversity and prevalence of parasites of domestic pigeons (Columba livia domestica) in a selected semiarid zone of South Khorasan, Iran.

Five species of nematodes and cestodes were collected from alimentary canals of pigeons: the nematodes were two species: Ascaridia colombae (16.66%) and Hadjelia truncata (1.96%), while the cestodes were Cotugnia digonopora (13.79%), Raillietina magninumida (18.62%) and Raillietina achinobothridia (32.35%); fecal examination revealed: Eimeria spp. (40.19%) and Cryptosporidium oocysts (2.94%); and blood smears showed: Haemoproteus cloumbae (47/05%); in mouth, throat and larynx: Trichomonans gallinae (57.84%); four species of ectoparasites were collected from feathers and subcutaneous nodules as follows: feathers: Pseudolynchia canariensis (63.72%), Columbicola columbae (79.41%), Menopen gallinea (44.11%); subcutaneous nodules: Laminosioptes cysticola (1.96%). From the parasitic fauna identified in this study, it is imperative to institute an integrated parasitic control through constant changing of litter, regular use of antihelminthics, anticoccidials and dusting of birds with pesticides.

Health assessment of captive tinamids (Aves, Tinamiformes) in Brazil.

Ninety-five (95) captive tinamids (Aves, Tinamiformes) of species Crypturellus obsoletus (brown tinamou), Crypturellus parvirostris (small-billed tinamou), Crypturellus tataupa (Tataupa tinamou), Crypturellus undulatus (undulated tinamou), Rhynchotus rufescens (red-winged tinamou), and Tinamus solitarius (solitary tinamou) were evaluated for diseases of mandatory control in the Brazilian Poultry Health Program (PNSA). Antibodies were detected by serum agglutination test (SAT) in 4 birds for Mycoplasma gallisepticum (MG) and in 27 birds for Salmonella Pullorum (SP) and Salmonella Gallinarum (SG). However, by hemagglutination inhibition (HI), sera were negative to MG and Mycoplasma synoviae (MS). Bacteriology was negative for SP and SG. No antibody was detected by HI to avian paramyxovirus type 1. However, antibodies to infectious bursal disease virus were detected in 9.4% (9/95) by ELISA. Fecal parasitology and necropsy revealed Capillaria spp. in 44.2% (42/95), Eimeria rhynchoti in 42.1% (40/95), Strongyloides spp. in 100% (20/20), Ascaridia spp., and unknown sporozoa in small-billed tinamou. Ectoparasites were detected in 42.1% (40/95) by inspection, and collected for identification. The louse Strongylocotes lipogonus (Insecta: Phthiraptera) was found on all Rhynchotus rufescens. An additional four lice species were found on 14 individuals. Traumatic lesions included four individual R. rufescens (4/40, 10%) with rhinotheca fracture, one with mandible fracture and three with posttraumatic ocular lesions (3/40, 7.5%). One C. parvirostris had phalangeal loss, another had tibiotarsal joint ankylosis and another had an open wound on the foot. Results suggest that major poultry infections/ diseases may not be relevant in tinamids, and that this group of birds, as maintained within distances for biosecurity purposes, may not represent a risk to commercial poultry. Ecto- and endoparasites were common, disseminated, and varied; regular monitoring of flocks is recommended for best performance.

Change in beak overhangs of cliff swallows over 40 years: Partly a response to parasites?

Some birds exhibit a maxillary overhang, in which the tip of the upper beak projects beyond the lower mandible and may curve downward. The overhang is thought to help control ectoparasites on the feathers. Little is known about the extent to which the maxillary overhang varies spatially or temporally within populations of the same species. The colonial cliff swallow (Petrochelidon pyrrhonota) has relatively recently shifted to almost exclusive use of artificial structures such as bridges and highway culverts for nesting and consequently has been exposed to higher levels of parasitism than on its ancestral cliff nesting sites. We examined whether increased ectoparasitism may have favored recent changes in the extent of the maxillary overhang. Using a specimen collection of cliff swallows from western Nebraska, USA, spanning 40 years and field data on live birds, we found that the extent of the maxillary overhang increased across years in a nonlinear way, peaking in the late 2000's, and varied inversely with cliff swallow colony size for unknown reasons. The number of fleas on nestling cliff swallows declined in general over this period. Those birds with perceptible overhangs had fewer swallow bugs on the outside of their nest, but they did not have higher nesting success than birds with no overhangs. The intraspecific variation in the maxillary overhang in cliff swallows was partly consistent with it having a functional role in combatting ectoparasites. The temporal increase in the extent of the overhang may be a response by cliff swallows to their relatively recent increased exposure to parasitism. Our results demonstrate that this avian morphological trait can change rapidly over time.

Oral trichomonosis: Description and severity of lesions in birds in Spain.

Avian trichomonosis is a parasitic disease caused by the flagellated protozoan Trichomonas gallinae. Columbiformes are the reservoir host of the parasite, with high levels of infection, but also other domestic and wild birds from a variety of orders are susceptible to the infection and development of gross lesions. In this paper we describe the type and severity of lesions in wild birds in four avian orders (Accipitriformes, Falconiformes, Strigiformes and Columbiformes). A total of 94 clinical cases diagnosed of trichomonosis were selected for the categorization of their lesions in the upper digestive tract. The affected birds were classified into three different categories (mild, moderate and severe) based on size (in relation to the tracheal opening), depth and location of the lesions. Mild cases are those with small and superficial lesions far from the oropharyngeal opening; moderate cases possess larger and deeper lesions, and severe cases very large and deep lesions that impede swallowing or affect the skull. Mild lesions were found in 10.6 % of cases; moderate lesions were observed in 18.1 % of the birds and severe lesions in 71.3 %. Treatment outcomes in birds with either mild or moderate lesions were favorable, while severe lesions were related to poor body score, leading to death or euthanasia in most cases. A relationship between severe lesions and avian order was found, with a higher percentage of birds with this type in Falconiformes, Columbiformes and Strigiformes. Multifocal lesions were more frequent in Columbiformes and Falconiformes. In Strigiformes, 93.3 % of birds showed lesions in the upper jaw. This study seeks to further understanding of avian trichomonosis and to provide information that will be useful to veterinarians and related professionals for assessment, prognosis and treatment choice for these birds.

Morphological and Molecular Characteristics of the Gastro-Intestinal Nematode Parasite Ascaridia columbae Infecting the Domestic Pigeon Columba livia domestica in Saudi Arabia.

BACKGROUND: Parasitism is a complex problem that is often ignored in companion animals, including birds, unless it develops into a severe clinical disorder. The present study was, therefore, aimed to investigate the presence of the gastrointestinal nematode infecting the domestic pigeon and provide a complete morphological description and clarify its taxonomic position through phylogenetic analysis of the ITS1-5.8s-ITS2 rDNA gene region. MATERIALS AND METHODS: During the current study, a total of twenty-six domestic pigeons, Columba livia domestica, were collected and internal organs examined for helminth detection. Using light and scanning electron microscopy, the recovered parasite species are studied. In addition, the selected gene region was obtained and sequenced using appropriate primers that aid in the formation of the phylogenetic dendrogram for the recovered parasite species with others retrieved from GenBank. RESULTS: Morphological examination showed that this nematode parasite belongs to the Ascaridiidae family within the genus Ascaridia. The material was assigned to the previously described Ascaridia columbae by providing all the characteristic features as the presence of a mouth opening surrounded by three tri-lobed lips; each lip has two triangular teeth with a spoon-like structure, cephalic papillae and amphidal pores on lips surface, presence of lateral cuticular alae and pre-cloacal sucker, 10 pairs of caudal papillae, and two equal spicules in male worms. The morphological investigations of this species were supplemented by molecular analysis of ITS1-5.8s-ITS2 rDNA gene region. The data showed that the present A. coulmbae is deeply embedded in the Ascaridia genus with a 74-99% sequence similarity to other species in the Chromadorea class. Ascaridiidae appears as monophyly and represented as a sister group to Heterakidae. The ascaridiid species examined belong to the Ascaridia genus and displaced a close relationship with the previously described A. coulmbae (gb| KF147909.1, gb| AJ001509.1, gb| KC905082.1, gb| JQ995321.1, gb| JX624729.1) as putative sister taxa. CONCLUSION: The present study revealed that the species Ascaridia is the first account of this genus as an endoparasite from the domestic pigeon inhabiting Saudi Arabia. Therefore, the combination of morphological and molecular studies helps to identify this species correctly and identified as Ascaridia columbae.

Redescription of Porrocaecum semiteres (Zeder, 1800) (Nematoda: Ascaridida) from the Song Thrush Turdus philomelos (Passeriformes: Turdidae).

INTRODUCTION: Porrocaecum semiteres (Zeder, 1800) (Ascaridida: Ascaridoidea) occurs frequently in various birds in Europe. However, the knowledge of the morphology of this species remains insufficient. METHODS: Light and scanning electron microscopy were used to study the detailed morphology of adults of P. semiteres based on newly collected specimens from Turdus philomelos in the Czech Republic. RESULTS: Some previously unreported morphological features were revealed, including the presence of a medio-apical notch, 70-80 small conical denticles and one pair of submedial pores on each lip, the absence of caudal alae, the presence of four pairs of postcloacal papillae, and a single, medio-ventral precloacal papilla.

Mixed infection by Libyostrongylus douglassii and L. dentatus (Nematoda: Trichostrongylidae) in Struthio camelus (Ratites: Struthioniformes) from Brazil with further morphological characterization of adults.

The genus Libyostrongylus includes three species, L. douglassii, L. dentatus and L. magnus that occur as parasites in the proventriculus of Struthio camelus. We confirmed a mixed infection by L. douglassii and L. dentatus in farmed ostriches from the southeast of Brazil for the first time, and provided new information on some morphological characters that differentiate these species. Adult nematodes collected from the proventriculus of ostriches were observed by light and scanning electron microscopy. Morphologic characterization and morphometric analysis of the nematodes enabled the distinction of both species and corroborated results of prior studies. Specimens of L. dentatus have a buccal capsule with a prominent esophageal tooth. Furthermore, males and females of L. dentatus were larger (4954 and 9347 microm) than those of L. douglassii (3411 and 4229 microm), but measurements for most characters in both species were smaller then those previously reported. Besides, the cephalic structure based on scanning electron microscopy differs, and L. dentatus has thick lips with round papillae, whereas L. douglassii has fine lips with lengthened papillae. The confirmation of both species in South America strongly suggests that the mixed infection may be common in farmed ostriches.

Link Between the Adult and the Metacercaria of Clinostomum heluans Braun, 1899 (Trematoda: Clinostomidae) Through DNA Sequences, and its Phylogenetic Position Within the Genus Clinostomum Leidy, 1856.

The phylogenetic position of Clinostomum heluans Braun, 1899 within the genus Clinostomum Leidy, 1856 is reported in this study based on sequences of the barcoding region of the mitochondrial cytochrome c oxidase subunit 1 gene ( COX1). Additionally, molecular data are used to link the adult and the metacercariae of the species. The metacercariae of C. heluans were found encysted infecting the cichlid fish Australoheros sp. in Minas Gerais, Brazil, whereas the adults were obtained from the mouth cavity of the Great White Egret, Ardea alba, in Campeche, Mexico. The COX1 sequences obtained for the Mexican clinostomes and the Brazilian metacercaria were almost identical (0.2% molecular divergence), indicating conspecificity. Similar molecular divergence (0.2-0.4%) was found between sequences of C. heluans reported here and Clinostomum sp. 6 previously obtained from a metacercaria recovered from the cichlid Cichlasoma boliviense in Santa Cruz, Bolivia. Both maximum likelihood and Bayesian inference analyses unequivocally showed the conspecificity between C. heluans and Clinostomum sp. 6, which form a monophyletic clade with high nodal support and very low genetic divergence. Moreover, tree topology reveals that C. heluans occupies a basal position with respect to New World species of Clinostomum, although a denser taxon sampling of species within the genus is further required. The metacercaria of C. heluans seems to be specific to cichlid fish because both samples from South America were recovered from species of this fish family, although not closely related.

A new genus and species of acuarioid nematode (Acuariidae: Seuratiinae) in petrels Pterodroma externa and P. neglecta from the Juan Fernández Islands, Chile.

A new genus and species of Seuratiinae is described based on adults recovered from the Juan Fernández and Kermedec Petrels (Pterodroma externa and P. neglecta) from the Juan Fernández Islands of Chile (south Pacific). Navonia pterodromae n. gen., n. sp. is distinguished from the other genera and species in Seuratiinae by the combination of the following characters: (1) cordons arising from commissures of buccal lips originating a finely denticulate collarette divided into 2 lateral lobes, and detached from underlying cuticle; (2) inconspicuous simple to bicuspid deirids; (3) presence of area rugosa; and (4) presence of a large left spicule in the male. It is also distinguished from some genera and species in this subfamily by the presence of a lateral furrow. Seuratia shipleyi was also recorded from P. externa. These are the first records of helminths in these 2 hosts and the first records of Seuratiinae from Chile.

Nematode parasites of the Chilean Flamingo, Phoenicopterus chilensis (Phoenicopteridae) from Central Argentina, with a description of a new species of Tetrameres (Tetrameridae).

During the summer of 2013, several specimens of Phoenicopterus chilensis (Phoenicopteridae) were found dead from unknown causes, in lakes from the endorheic system "Encadenadas del Oeste", Buenos Aires Province, Argentina. Two species of Nematoda were recovered from the proventriculus, one of them new for science. The tetramerid Tetrameres (Tetrameres) salina n. sp. is mainly characterized by having reduced pseudolabia, lips absent, six bifid teeth, males with lateral alae, four rows of somatic spines and length ratio of spicules 1:12-32, and large females with eggs lacking polar filaments. The acuariid, Echinuria skrjabinensis is described and illustrated, this finding represent the second report of this nematode in Argentina and the first record in flamingos. This is the first record of helminths parasitizing wild Chilean Flamingos, but it is not possible to ensure that they accomplish their life cycle in this system of lakes, because the migratory movements of the population of flamingos studied are unknown.

Ecomorphology of parasite attachment: experiments with feather lice.

The host specificity of some parasites can be reinforced by morphological specialization for attachment to mobile hosts. For example, ectoparasites with adaptations for attaching to hosts of a particular size might not be able to remain attached to larger or smaller hosts. This hypothesis is suggested by the positive correlation documented between the body sizes of many parasites and their hosts. We adopted an ecomorphological approach to test the attachment hypothesis. We tested the ability of host-specific feather lice (Phthiraptera: Ischnocera) to attach to 6 novel species of pigeons and doves that vary in size by nearly 2 orders of magnitude. Surprisingly, Rock Pigeon lice (Columbicola columbae) remained attached equally well to all 6 novel host species. We tested the relative importance of 3 factors that could facilitate louse attachment: whole-body insertion, tarsal claw use, and mandible use. Insertion, per se, was not necessary for attachment. However, insertion on coarse feathers of large hosts allowed lice to access feather barbules with their mandibles. Mandible use was a key component of attachment regardless of feather size. Attachment constraints do not appear to reinforce host specificity in this system.

Do mosquitoes transmit the avian malaria-like parasite Haemoproteus? An experimental test of vector competence using mosquito saliva.

BACKGROUND: The life-cycle of many vector-borne pathogens includes an asexual replication phase in the vertebrate host and sexual reproduction in the insect vector. However, as only a small array of parasites can successfully develop infective phases inside an insect, few insect species are competent vectors for these pathogens. Molecular approaches have identified the potential insect vectors of blood parasites under natural conditions. However, the effectiveness of this methodology for verifying mosquito competence in the transmission of avian malaria parasites and related haemosporidians is still under debate. This is mainly because positive amplifications of parasite DNA in mosquitoes can be obtained not only from sporozoites, the infective phase of the malaria parasites that migrate to salivary glands, but also from different non-infective parasite forms in the body of the vector. Here, we assessed the vectorial capacity of the common mosquito Culex pipiens in the transmission of two parasite genera. METHODS: A total of 1,560 mosquitoes were allowed to feed on five house sparrows Passer domesticus naturally infected by Haemoproteus or co-infected by Haemoproteus/Plasmodium. A saliva sample of the mosquitoes that survived after 13 days post-exposure was taken to determine the presence of parasite DNA by PCR. RESULTS: Overall, 31.2% mosquito's head-thorax and 5.8% saliva samples analysed showed positive amplifications for avian malaria parasites. In contrast to Haemoproteus DNA, which was not found in either the body parts or the saliva, Plasmodium DNA was detected in both the head-thorax and the saliva of mosquitoes. Parasites isolated from mosquitoes feeding on the same bird corresponded to the same Plasmodium lineage. CONCLUSIONS: Our experiment provides good evidence for the competence of Cx. pipiens in the transmission of Plasmodium but not of Haemoproteus. Molecular analyses of saliva are an effective method for testing the vector competence of mosquitoes and other insects in the transmission of vector-borne pathogens.

Renal trematodiasis in captive double-toothed barbets (Lybius bidentatus).

Two double-toothed barbets (Lybius bidentatus) were swallowed and regurgitated by a snake within a free-flight aviary. Trematodes were observed histopatholgically within the renal pelvises and proximal ureters with associated mucosal hyperplasia and mild heterohistiocytic inflammation in both birds. Trematodes were identified as Tanaisia (Tamerlania) zarudnyi, which have a life cycle involving terrestrial snails. Trematodes have been reported within kidneys in several orders of birds, including the Columbiformes, Passeriformes, Stercorariidae, Anseriformes, Galliformes, and Piciformes. Snails were not uncommon within the barbets' aviary and may have been the source of exposure. Renal trematodiasis is probably an incidental finding in these birds because there were no clinical signs and the birds lacked pronounced histologic lesions in the kidney that would be associated with ureteral or pelvic obstruction.