blood parasites of some waterfowl from victoria, australia.a total of 316 anatids (5 species) from serendip wildlife research station, lara, victoria, were examined for blood parasites. twenty-two of the ducks (all five species) harbored haemoproteus nettionis and one also harbored plasmodium relictum. none of 12 dusky moorhens (gallinula tenebrosa) were infected. there was no significant difference in the prevalence of h. nettionis between species or age groups of ducks. no evidence of infection with leucocytozoon, trypanosoma or microfilaria was obtai ...1977405511
avian malaria in african black-footed penguins.ten captive-reared african black-footed penguins (spheniscus demersus) from a large outdoor colony were monitored for avian malaria, using several diagnostic tests. one treatment regimen was evaluated. thin smear blood evaluation enabled detection of seven parasitemias involving plasmodium relictum and plasmodium elongatum in the penguins. leukocytosis (relative lymphocytosis) was characteristic of infected birds. parasitemia was detected as early as 21 days prior to onset of clinical signs (dep ...1979521378
use of amino acids by plasmodium relictum oocysts in vitro. 19761253879
plasmodium relictum as a cause of avian malaria in wild-caught magellanic penguins (spheniscus magellanicus).avian malaria (plasmodium relictum) caused significant mortality in wild-caught magellanic penguins (spheniscus magellanicus) in 1986 at the blank park zoo in des moines, iowa (usa). in early winter, wild birds were captured off the southern coast of chile and flown to detroit, michigan for a 38 day quarantine. after quarantine, 18 birds were dispersed to lansing, michigan, six to a facility in maine, and 46 to des moines, iowa. upon arrival in des moines, several penguins became weak and inacti ...19883193555
effects of plasmodium relictum on the metabolic rate and body temperature in canaries (serinus canarius). 19873625437
the cultivation of plasmodium relictum in mosquito cell lines. 19714396509
spring relapse of plasmodium relictum infections in an experimental field population of english sparrows (passer domesticus). 19715138979
cross immunity between plasmodium relictum and plasmodium lophurae in chickens. 19695349499
cross immunity between plasmodium relictum and plasmodium lophurae in chickens. 19695389917
extraction of haemoproteus columbae (haemosporina: haemoproteidae) antigen from rock dove pigeons (columba livia) and its use in an antibody elisa.erythrocytic stages of haemoproteus columbae were extracted from the cytoplasm of nucleated red blood cells (rbc) of rock dove pigeons (columba livia) using cationic detergent (n,n',n'-polyoxyethylene(10)-n-tallow-1,3-diaminopropane [edta-20]) and discontinuous percoll gradient density. crude rbc extract (crbce) antigen was prepared. parasitized rbcs were more resistant to edta-20 action than unparasitized cells. an enzyme-linked immunosorbent assay (elisa) was developed for detection of anti-h. ...19947931906
subclinical avian malaria infections in african black-footed penguins (spheniscus demersus) and induction of parasite recrudescence.the subclinical and clinical plasmodium elongatum and plasmodium relictum infections of captive-reared african black-footed penguins (spheniscus demersus) were evaluated in nine adult and 29 juvenile penguins in the baltimore zoo (maryland, usa) during summer 1988 and winter 1989. two diagnostic methods were used: giemsa-stained thin blood films, and subinoculation of penguin blood into 1-day-old peking ducklings. chloroquine and primaquine treatment was applied to all parasitemic juvenile pengu ...19947933280
elisa method for detecting anti-plasmodium relictum and anti-plasmodium elongatum antibody in infected duckling sera using plasmodium falciparum enzyme-linked immunosorbent assay (elisa) with 3 plasmodium falciparum nf-54 antigens, r32tet32, p.f.r27, and crude red blood cell extract (crbce), was tested for detection of anti-plasmodium relictum and anti-plasmodium elongatum antibodies in sera from experimentally infected ducklings. whole blood, serum, and dried blood on filter paper gave similar results. the latter was selected for convenience. all birds infected by experimental blood challenge, but not exposed to sporozoites, had dete ...19938277381
wildlife disease and conservation in hawaii: pathogenicity of avian malaria (plasmodium relictum) in experimentally infected iiwi (vestiaria coccinea). 19958632925
hematozoa in two populations of the threatened red-billed chough in spain.the prevalence of hematozoa in two populations of red-billed choughs (pyrrhocorax pyrrhocorax) was sampled in 1992 and 1994 in spain. two blood parasites infected red-billed choughs. a species of plasmodium, possibly plasmodium relictum, and the piroplasm babesia frugilegica, are described for the first time from this host. low prevalence (1/178, < 1%) of hematozoa in these populations, was evidence for a lack of effects of blood parasites on the life history and conservation of this threatened ...19979249715
serological responses and immunity to superinfection with avian malaria in experimentally-infected hawaii amakihi.six of seven hawaii amakihi (hemignathus virens) with chronic malarial infections had no increases in peripheral parasitemia, declines in food consumption, or loss of body weight when rechallenged with the homologous isolate of plasmodium relictum 61 to 62 days after initial infection. five uninfected control amakihi exposed at the same time to infective mosquito bites developed acute infections with high parasitemias. reductions in food consumption and loss of body weight occurred in all contro ...200111272498
a comparison of the blood parasites in three subspecies of the yellow wagtail motacilla and eighty yellow wagtails motacilla flava belonging to 3 subspecies (motacilla flava feldegg, motacilla flava flava, motacilla flava thunbergi) were caught during the spring migration in south kazakhstan and investigated by microscopic examination of stained blood smears. haemoproteus anthi, haemoproteus motacillae, leucocytozoon fringillinarum, leucocytozoon majoris, plasmodium relictum, plasmodium polare, atoxoplasma sp., trypanosoma sp., and microfilariae were identified. the ove ...200111534666
comparative development of plasmodium relictum oocysts in anopheles quadrimaculatus, a. albimanus, and culex pipiens. 195313035579
[relation of nyctohemeral rhythm of birds to mass cycle of plasmodium relictum]. 195313063055
[studies on blood parasites. iv. behavior of a strain of plasmodium relictum in pigeons]. 195313112728
susceptibility of culex (culex) bitaeniorhynchus giles, 1901, to plasmodium relictum but not to plasmodium gallinaceum and plasmodium falciparum. 195513262831
experimental studies of concurrent infection of canaries and of the mosquito culex tarsalis with plasmodium relictum and western equine encephalitis virus. 195613292656
[tissue stages of plasmodium relictum s strain]. 195613321386
changes in infectivity of plasmodium relictum for avian hosts. 195613375680
development in vitro of isolated oocysts of plasmodium relictum. 195713463685
[action of combined primaquine-pyrimethamine. i. experimental study on pigeons (columba livia) infected with plasmodium relictum]. 195713474136
a new host record for plasmodium relictum: the silver gull (larus novae-hollandiae stephens). 196113759689
in vitro development of the mosquito phase of plasmodium relictum. 196013796224
[contribution to the study of the influence of the nyctohemeral environment of the host on the multiplication of plasmodium relictum]. 195913815825
infectivity to canaries of sporozoites of plasmodium relictum developing in vitro. 196113864409
the effect of low temperature on plasmodium relictum in culex tarsalis. 196213878142
temperature stresses on the mosquito phase of plasmodium relictum. 196414244806
[latent infection and premunition in malaria in sparrows due to plasmodium relictum]. 196014445035
acquired resistance to chloroguanide in the pigeon strain of plasmodium relictum (grassi and feletti, 1891). 195014795203
observations on the pre-erythrocytic stages of plasmodium relictum, plasmodium cathemerium, and plasmodium gallinaceum in various birds. 195114803745
transmission of plasmodium relictum grassi & feletti by anopheles freeborni aitken. 195114828372
comparative susceptibility of four anopheline mosquitoes to plasmodium relictum. 195114880901
[remarks on the association of plasmodium relictum and plasmodium rouxi malaria in the same birds]. 195214944294
measuring the effects of an ever-changing environment on malaria control.the effectiveness of malaria control measures depends not only on the potency of the control measures themselves but also upon the influence of variables associated with the environment. environmental variables have the capacity either to enhance or to impair the desired outcome. an optimal outcome in the field, which is ultimately the real goal of vaccine research, will result from prior knowledge of both the potency of the control measures and the role of environmental variables. here we descr ...200415039349
pathogenic subspecies of plasmodium relictum found in african birds. 200515786929
malaria in a captively-produced f1 gyrfalcon and in two f. peregrine falco rusticolus and two of 24 falco peregrinus were positive for plasmodium relictum. sixteen percent of the erythrocytes (rbc) of the gyrfalcon were parasitized. following treatment with chloroquine the parasite burden was dramatically reduced (to less than 0.01%). infection in peregrine falcons was low (0.01-0.4% rbcs were parasitized). this is the second report of plasmodium in the gyrfalcon and the first report in the peregrine falcon.197616502699
mechanism of spring relapse in avian malaria: effect of gonadotropin and corticosterone.previous work demonstrated that corticosterone induces relapse of avian malaria, and that this effect varies markedly from winter to spring. in the present study, english sparrows with latent plasmodium relictum infections were treated in winter with corticosterone, gonadotropin, corticosterone + gonadotropin, or a control regimen consisting of the oil vehicle. gonadotropin neither induced relapse nor potentiated the induction of relapse by corticosterone. these data cast doubt on the hypothesis ...197016512154
dynamics of parasitemia of malaria parasites in a naturally and experimentally infected migratory songbird, the great reed warbler acrocephalus arundinaceus.little is known about the development of infection of malaria parasites of the genus plasmodium in wild birds. we used qpcr, targeting specific mitochondrial lineages of plasmodium ashfordi (grw2) and plasmodium relictum (grw4), to monitor changes in intensities of parasitemia in captive great reed warblers acrocephalus arundinaceus from summer to spring. the study involved both naturally infected adults and experimentally infected juveniles. the experiment demonstrated that p. ashfordi and p. r ...200818280472
blood parasites of house finches (carpodacus mexicanus) from georgia and new york.this study investigated the ecology of hematozoan parasites in two eastern populations of house finch (carpodacus mexicanus). blood smears were obtained from birds captured in georgia during 2001-2003 (n = 757) and new york during 2001 (n = 282) and evaluated for the presence of hematozoans. low-density infections of haemoproteus fringillae and plasmodium relictum were confirmed at each location. infections were observed year-round in georgia, but primarily between june and november in new york. ...200818436682
genetic characterization of hawaiian isolates of plasmodium relictum reveals mixed-genotype infections.the relatively recent introduction of a highly efficient mosquito vector and an avian pathogen (plasmodium relictum) to an isolated island ecosystem with naïve, highly susceptible avian hosts provides a unique opportunity to investigate evolution of virulence in a natural system. mixed infections can significantly contribute to the uncertainty in host-pathogen dynamics with direct impacts on virulence. toward further understanding of how host-parasite and parasite-parasite relationships may impa ...200818578879
concurrent infection with clostridium and plasmodium in a captive king penguin aptenodytes patagonicus.concurrent infection with plasmodium relictum and clostridium perfringens type b was diagnosed in a king penguin (aptenodytes patagonicus) that died in the national zoological gardens, pretoria. macro- and microscopic pathological changes were mainly due to c. perfringens. the relative significance of the two pathogens is discussed.199418671104
plasmodium relictum (lineage p-sgs1): effects on experimentally infected passerine birds.we evaluated the effects of plasmodium relictum (lineage p-sgs1), which is a host generalist, to five species of passerine birds. light infection of p. relictum was isolated from a naturally infected adult reed warbler acrocephalus scirpaceus. the parasites were inoculated to naive juveniles of the chaffinch fringilla coelebs, common crossbill loxia curvirostra, house sparrow passer domesticus, siskin spinus spinus and starling sturnus vulgaris. susceptibility of these birds to the infection of ...200818809402
natural immunity and susceptibility of doves and pigeons to pre-erythrocytic and erythrocytic stages of plasmodium relictum. 194818872918
extended persistence of plasmodium relictum in culture. 194818889623
a nucleotide-constrained single base extension method for improved detection of minority alleles in genetically mixed plasmodium infections, minority alleles may have a significant role in drug resistance and other responses to selective pressures. many available methods to detect single nucleotide polymorphisms representing minority alleles either are not sensitive enough to detect these rare alleles or are limited in the number of loci to be screened in a single reaction. in order to achieve highly sensitive, multiplex snp genotyping, we have developed a nucleotide-constrained method base ...200919026693
experimental infection of hawai'i 'amakihi (hemignathus virens) with west nile virus and competence of a co-occurring vector, culex quinquefasciatus: potential impacts on endemic hawaiian avifauna.introduced mosquito-borne avian disease is a major limiting factor in the recovery and restoration of native hawaiian forest birds. annual epizootics of avian pox (avipoxvirus) and avian malaria (plasmodium relictum) likely led to the extinction of some species and continue to impact populations of susceptible hawaiian honeycreepers (drepanidinae). the introduction of a novel pathogen, such as west nile virus (wnv), could result in further population declines and extinctions. during september an ...200919395735
bloodmeal identification and detection of avian malaria parasite from mosquitoes (diptera: culicidae) inhabiting coastal areas of tokyo bay, japan.bloodmeal identification and the detection of avian malaria parasite from mosquitoes (diptera: culicidae) were carried out by polymerase chain reaction-based methods for field samples collected in coastal areas of tokyo bay, japan, from april to october 2007. the following seven mosquito species were collected: aedes albopictus (skuse), culex pipiens pallens coquillett, culex pipiens form molestus forskal, culex tritaeniorhynchus giles, culex inatomii kamimura & wada, culex bitaeniorhynchus gile ...200919769059
thermal constraints to the sporogonic development and altitudinal distribution of avian malaria plasmodium relictum in hawai'i.more than half of the hawaiian honeycreepers (drepanidinae) known from historical records are now extinct. introduced mosquito-borne disease, in particular the avian malaria plasmodium relictum , has been incriminated as a leading cause of extinction during the 20th century and a major limiting factor in the recovery of remaining species populations. today, most native hawaiian bird species reach their highest densities and diversity in high elevation (>1,800 m above sea level) forests. we deter ...201020001096
the response of blood-inoculated and sporozoite-induced infections of plasmodium relictum to drugs. 194720255202
extended persistence of oocysts of plasmodium relictum in culture. 194720271937
growth of protozoa in tissue culture; plasmodium relictum, exoerythrocytic forms. 194620275229
the morphology of cryptozoites and metacryptozoites of plasmodium relictum and the relationship of these stages to parasitemia in canaries and pigeons. 194720292843
[extraerythrocytic form of plasmodium relictum]. 194620341110
prevalence and distribution of pox-like lesions, avian malaria, and mosquito vectors in kipahulu valley, haleakala national park, hawai'i, usa.we determined prevalence and altitudinal distribution of introduced avian malarial infections (plasmodium relictum) and pox-like lesions (avipoxvirus) in forest birds from kipahulu valley, haleakalā national park, on the island of maui, and we identified primary larval habitat for the mosquito vector of this disease. this intensively managed wilderness area and scientific reserve is one of the most pristine areas of native forest remaining in the state of hawai'i, and it will become increasingly ...200717984251
genetic structure and evolved malaria resistance in hawaiian honeycreepers.infectious diseases now threaten wildlife populations worldwide but population recovery following local extinction has rarely been observed. in such a case, do resistant individuals recolonize from a central remnant population, or do they spread from small, perhaps overlooked, populations of resistant individuals? introduced avian malaria (plasmodium relictum) has devastated low-elevation populations of native birds in hawaii, but at least one species (hawaii amakihi, hemignathus virens) that wa ...200717944845
hemosporidian blood parasites in seabirds--a comparative genetic study of species from antarctic to tropical habitats.whereas some bird species are heavily affected by blood parasites in the wild, others reportedly are not. seabirds, in particular, are often free from blood parasites, even in the presence of potential vectors. by means of polymerase chain reaction, we amplified a dna fragment from the cytochrome b gene to detect parasites of the genera plasmodium, leucocytozoon, and haemoproteus in 14 seabird species, ranging from antarctica to the tropical indian ocean. we did not detect parasites in 11 of the ...201020652673
larval habitat for the avian malaria vector culex quinquefasciatus (diptera: culicidae) in altered mid-elevation mesic-dry forests in hawai'i.effective management of avian malaria (plasmodium relictum) in hawai'i's endemic honeycreepers (drepanidinae) requires the identification and subsequent reduction or treatment of larval habitat for the mosquito vector, culex quinquefasciatus (diptera: culicidae). we conducted ground surveys, treehole surveys, and helicopter aerial surveys from 2001-2003 to identify all potential larval mosquito habitat within two 100+ ha mesic-dry forest study sites in hawai'i volcanoes national park, hawai'i; ' ...200920836824
parasite diversity in an endemic region for avian malaria and identification of a parasite causing penguin mortality.understanding the population structure of plasmodium parasites is essential for malaria intervention. a survey of parasites in vectors and host infections was conducted in an area of intense mortality due to malaria in a captive penguin (spheniscus demersus) colony, using a novel method for identification of plasmodium species by amplification of ribosomal sequences in dna or rna. three phylogenetically distinct groups of avian plasmodium were detected in mosquitoes (culex) collected at the stud ...19968822810
the relation of natural and acquired immunity of various avian hosts to the cryptozoites and metacryptozoites of plasmodium gallinaceum and plasmodium relictum. 194621025253
plasmodium relictum (lineage sgs1) and plasmodium ashfordi (lineage grw2): the effects of the co-infection on experimentally infected passerine birds.the effects of avian malaria parasites of the genus plasmodium on their hosts are insufficiently understood. this is particularly true for malarial co-infections, which predominant in many bird populations. we investigated effects of primary co-infection of plasmodium relictum (lineage sgs1) and plasmodium ashfordi (grw2) on experimentally infected naive juveniles of siskin spinus spinus, crossbill loxia curvirostra and starling sturnus vulgaris. all siskins and crossbills were susceptible but s ...201021050849
characteristics of naturally acquired plasmodium relictum capistranoae infections in naive hawaiian crows (corvus hawaiiensis) in hawaii.indigenous to hawaii, the hawaiian crow (corvus hawaiiensis) is the world's most severely endangered species with only 3 reproductively active pairs remaining in the wild. seven captive-reared, avian malaria-naive c. hawaiiensis were exposed in an outdoor aviary and hematologically and serologically monitored for 9 wk. three birds showed plasmodium relictum capistranoae parasitemia (6.35%, 2.15%, and 0.60%). all birds were seroconverted for malaria on week 7 as determined by enzyme-linked immuno ...19968627494
an elisa for detecting anti-plasmodium spp. antibodies in african black-footed penguins (spheniscus demersus).an enzyme-linked immunosorbent assay (elisa) utilizing 3 plasmodium falciparum antigens, r32tet32, p.f.r27, and crude red blood cell extract, was developed for the detection of circulating anti-plasmodium relictum or anti-plasmodium elongatum antibodies in sera from naturally infected adult african black-footed penguins (spheniscus demersus) at the baltimore zoo, maryland. a concentration of 2.0 micrograms/ml of each antigen was optimal in terms of specificity, sensitivity, and test speed. it wa ...19948308660
hematologic characteristics of avian malaria cases in african black-footed penguins (spheniscus demersus) during the first outdoor exposure season.twenty-nine juvenile, captive-reared african black-footed penguins (spheniscus demersus) were hematologically monitored every 2 wk over the period of 24 wk during their first outdoor exposure. blood samples taken from the penguins were screened for 12 blood evaluation parameters. parasitemic penguins were medically treated. eighteen birds (62.1%) experienced naturally acquired malaria and 11 birds (37.9%) remained nonparasitemic. a total of 32 avian malaria episodes were noted; 25 (78.1%) were i ...19948158474
characteristics of naturally acquired avian malaria infections in naive juvenile african black-footed penguins (spheniscus demersus).antibody responses to naturally acquired plasmodium relictum and p. elongatum infections, blood parasitemia, and disease signs were investigated in 23 naive juvenile african black-footed penguins (spheniscus demersus). anti-plasmodium spp. immunoglobulins were detected by enzyme-linked immunosorbent assay (elisa) using p. falciparum antigens. all birds rapidly developed antibody to p. relictum and p. elongatum. five penguins showed detectable parasitemia and signs of the disease. parasitemia was ...19947886030
evaluation of serum chemistry values associated with avian malaria infections in african black-footed penguins (spheniscus demersus).the value profiles of 5 intracellular enzymes, 15 metabolites (with 2 associated ratios), and 3 electrolytes were monitored over time in 9 captive-reared african black-footed penguins (spheniscus demersus) with different avian malaria clinical status: uninfected, subclinically infected, and clinically infected with fatal outcome. fatal infections were caused by plasmodium relictum. numerous schizonts were visible in the lungs, liver, spleen, and interstitial tissue of the kidneys. the reference ...19957624290
comparative susceptibility of culex tarsalis, anopheles franciscanus, and culiseta inornata (diptera: culicidae) to plasmodium relictum (haemosporidia: plasmodiiae).repeated laboratory attempts failed to infect culiseta inornata (williston) and anopheles franciscanus mccracken with plasmodium relictum as efficiently as culex tarsalis coquillett controls. of 210 an. franciscanus that imbibed a replete meal from a parasitemic canary, two were found with oocysts and none with sporozoites. of 112 cs. inornata similarly fed, seven contained oocysts and one contained sporozoites. in contrast, of 94 cx. tarsalis tested, 80 (85%) were found with oocysts, thus confi ...19901967655
wolbachia increases susceptibility to plasmodium infection in a natural system.current views about the impact of wolbachia on plasmodium infections are almost entirely based on data regarding artificially transfected mosquitoes. this work has shown that wolbachia reduces the intensity of plasmodium infections in mosquitoes, raising the exciting possibility of using wolbachia to control or limit the spread of malaria. whether natural wolbachia infections have the same parasite-inhibiting properties is not yet clear. wolbachia-mosquito combinations with a long evolutionary h ...201424500167
parasite cultivation in relation to research on the chemotherapy of malaria.attempts to develop techniques for the continuous in vitro cultivation of the malaria parasite have not yet proved successful. it has not been possible to obtain the complete sporogonic development of the parasite in vitro although some progress was made with plasmodium relictum and p. berghei. exoerythrocytic stages of p. gallinaceum have been successfully cultivated in vitro in tissue explants and those of p. fallax have been grown in turkey primary embryo tissue cells. with the recent develop ...19761086733
transgenerational effect of infection in plasmodium-infected mosquitoes.transgenerational effects of infection have a huge potential to influence the prevalence and intensity of infections in vectors and, by extension, disease epidemiology. these transgenerational effects may increase the fitness of offspring through the transfer of protective immune factors. alternatively, however, infected mothers may transfer the costs of infection to their offspring. although transgenerational immune protection has been described in a dozen invertebrate species, we still lack a ...025762571
mosquito age and avian malaria infection.the immune system of many insects wanes dramatically with age, leading to the general prediction that older insects should be more susceptible to infection than their younger counterparts. this prediction is however challenged by numerous studies showing that older insects are more resistant to a range of pathogens. the effect of age on susceptibility to infections is particularly relevant for mosquitoes given their role as vectors of malaria and other diseases. despite this, the effect of mosqu ...201526424326
effect of repeated exposure to plasmodium relictum (lineage sgs1) on infection dynamics in domestic canaries.parasites are known to exert strong selection pressures on their hosts and, as such, favour the evolution of defence mechanisms. the negative impact of parasites on their host can have substantial consequences in terms of population persistence and the epidemiology of the infection. in natural populations, however, it is difficult to assess the cost of infection while controlling for other potentially confounding factors. for instance, individuals are repeatedly exposed to a variety of parasite ...201020570591
avian malaria: a new lease of life for an old experimental model to study the evolutionary ecology of plasmodium.avian malaria has historically played an important role as a model in the study of human malaria, being a stimulus for the development of medical parasitology. avian malaria has recently come back to the research scene as a unique animal model to understand the ecology and evolution of the disease, both in the field and in the laboratory. avian malaria is highly prevalent in birds and mosquitoes around the world and is amenable to laboratory experimentation at each stage of the parasite's life c ...026150666
comparative susceptibility of introduced forest-dwelling mosquitoes in hawai'i to avian malaria, plasmodium identify potential vectors of avian malaria in hawaiian native forests, the innate susceptibility of aedes albopictus, wyeomyia mitchellii, and culex quinquefasciatus from 3 geographical sites along an altitudinal gradient was evaluated using local isolates of plasmodium relictum. mosquitoes were dissected 5-8 and 9-13 days postinfective blood meal and microscopically examined for oocysts and salivary-gland sporozoites. sporogony was completed in all 3 species, but prevalence between species ...200517089752
taxonomic status and re-description of plasmodium relictum (grassi et feletti, 1891), plasmodium maior raffaele, 1931, and description of p. bigueti n. sp. in sparrows.the first accurate re-description of plasmodium relictum (grassi et feletti, 1891) in its type host was provided by raffaele in 1931, and the name relictum should thus refer to this work. in his article, raffaele noted the presence of an associated but distinct species, p. maior. the work of raffaele has since remained overlooked, and the taxon relictum has been applied rather loosely to parasites found in numerous birds of diverse geographic origin. examination of passer domesticus specimens co ...200315267099
erythrocyte sedimentation rate in pigeons infected with plasmodium relictum. 195114825027
further observations on sporogony cycle of plasmodium relictum in a ddt-resistant strain of culex fatigans. 196013771710
disease screening of three breeding populations of adult exhibition budgerigars (melopsittacus undulatus) in new zealand reveals a high prevalence of a novel polyomavirus and avian malaria infection.disease surveillance is vital to the management of new zealand's endemic and threatened avian species. three infectious agents that are potential threats to new zealand's endemic birds include avian polyomavirus (apv), beak and feather disease virus (bfdv), and avian malaria. all three agents have been reported in new zealand; however, possible reservoir populations have not been identified. in this communication, we report the first study of apv, bfdv, and avian malaria in introduced adult exhi ...201424758122
a model for the prediction of relative titres of avian malaria and aspergillus spp. igg in jackass penguin (spheniscus demersus) females based on maternal igg in egg-yolk.a model for the prediction of igg titres in females of the jackass penguin (spheniscus demersus) was developed, based on igg which was maternally transmitted to the yolk of unembryonated eggs produced by these females. however, prediction of the female titre based on the titre of embryonated eggs may be inadequate. blood samples from 10 s. demersus females and their corresponding embryonated (n = 10) and unembryonated (n = 49) eggs were analysed by indirect elisa for avian malaria (plasmodium re ...19968894766
dispersal of culex quinquefasciatus (diptera: culicidae) in a hawaiian rain forest.introduced mosquito-borne pathogens avian malaria (plasmodium relictum grassi and feletti) and avian pox virus (avipoxvirus) have been implicated in the past extinctions and declines of hawaiian avifauna and remain significant obstacles to the recovery and restoration of endemic hawaiian birds. effective management of avian disease will require extensive mosquito control efforts that are guided by the local ecology of the vector culex quinquefasciatus say (diptera: culicidae). during october and ...200818714858
immunity, resistance and tolerance in bird-parasite interactions.interacting pathogens and hosts have evolved reciprocal adaptations whose function is to allow host exploitation (from the pathogen stand point) or minimize the cost of infection (from the host stand point). once infected, two strategies are offered to the host: parasite clearing (resistance) and withstanding the infection while paying a low fitness cost (tolerance). in both cases, the immune system plays a central role. interestingly, whatever the defence strategy adopted by the host, this is l ...201323800152
plasmodium relictum infection and mhc diversity in the house sparrow (passer domesticus).antagonistic coevolution between hosts and parasites has been proposed as a mechanism maintaining genetic diversity in both host and parasite populations. in particular, the high level of genetic diversity usually observed at the major histocompatibility complex (mhc) is generally thought to be maintained by parasite-driven selection. among the possible ways through which parasites can maintain mhc diversity, diversifying selection has received relatively less attention. this hypothesis is based ...201020943698
molecular identification of the chitinase genes in plasmodium relictum.malaria parasites need to synthesize chitinase in order to go through the peritrophic membrane, which is created around the mosquito midgut, to complete its life cycle. in mammalian malaria species, the chitinase gene comprises either a large or a short copy. in the avian malaria parasites plasmodium gallinaceum both copies are present, suggesting that a gene duplication in the ancestor to these extant species preceded the loss of either the long or the short copy in plasmodium parasites of mamm ...201424943514
landscape factors influencing the spatial distribution and abundance of mosquito vector culex quinquefasciatus (diptera: culicidae) in a mixed residential-agricultural community in hawai'i.mosquito-borne avian diseases, principally avian malaria (plasmodium relictum grassi and feletti) and avian pox (avipoxvirus sp.) have been implicated as the key limiting factor associated with recent declines of endemic avifauna in the hawaiian island archipelago. we present data on the relative abundance, infection status, and spatial distribution of the primary mosquito vector culex quinquefasciatus say (diptera: culicidae) across a mixed, residential-agricultural community adjacent to hawai' ...200717915520
pathogenicity of avian malaria in experimentally-infected hawaii amakihi.the introduction of avian malaria (plasmodium relictum) and mosquitoes (culex quinquefasciatus) to the hawaiian islands (usa) is believed to have played a major role in the decline and extinction of native hawaiian honeycreepers (drepanidinae). this introduced disease is thought to be one of the primary factors limiting recovery of honeycreepers at elevations below 1,200 m where native forest habitats are still relatively intact. one of the few remaining species of honeycreepers with a wide elev ...200010813599
fitness effects of endemic malaria infections in a wild bird population: the importance of ecological structure.1. parasites can have important effects on host populations influencing either fecundity or mortality, but understanding the magnitude of these effects in endemic host-parasite systems is challenging and requires an understanding of ecological processes affecting both host and parasite. 2. avian blood parasites (haemoproteus and plasmodium) have been much studied, but the effects of these parasites on hosts in areas where they are endemic remains poorly known. 3. we used a multistate modelling f ...201121426343
does avian malaria infection affect feather stable isotope signatures?it is widely accepted that stable isotope ratios in inert tissues such as feather keratin reflect the dietary isotopic signature at the time of the tissue synthesis. however, some elements such as stable nitrogen isotopes can be affected by individual physiological state and nutritional stress. using malaria infection experiment protocols, we estimated the possible effect of malaria parasite infections on feather carbon (+¦(13)c) and nitrogen (+¦(15)n) isotope signatures in juvenile common cross ...201121671039
seasonal variation in plasmodium prevalence in a population of blue tits cyanistes caeruleus.1. seasonal variation in environmental conditions is ubiquitous and can affect the spread of infectious diseases. understanding seasonal patterns of disease incidence can help to identify mechanisms, such as the demography of hosts and vectors, which influence parasite transmission dynamics. 2. we examined seasonal variation in plasmodium infection in a blue tit cyanistes caeruleus population over 3 years using sensitive molecular diagnostic techniques, in light of beaudoin et al.'s (1971; journ ...200818312339
identification of plasmodium relictum causing mortality in penguins (spheniscus magellanicus) from são paulo zoo, brazil.this study reports avian malaria caused by plasmodium relictum in magellanic penguins (spheniscus magellanicus) from são paulo zoo. the disease was highly infective among the birds and was clinically characterized by its acute course and high mortality. the penguins of são paulo zoo were housed for at least 2 years without malaria; however, they had always been maintained in an enclosure protected from mosquito exposure during the night period. when they presented pododermatitis, they were freed ...201020638795
parasites affect song complexity and neural development in a songbird.there is now considerable evidence that female choice drives the evolution of song complexity in many songbird species. however, the underlying basis for such choice remains controversial. the developmental stress hypothesis suggests that early developmental conditions can mediate adult song complexity by perturbing investment in the underlying brain nuclei during their initial growth. here, we show that adult male canaries (serinus canaria), infected with malaria (plasmodium relictum) as juveni ...200516191614
insecticide resistance and malaria transmission: infection rate and oocyst burden in culex pipiens mosquitoes infected with plasmodium relictum.the control of most vectors of malaria is threatened by the spread of insecticide resistance. one factor that has been hitherto largely overlooked is the potential effects of insecticide resistance on the ability of mosquitoes to transmit malaria: are insecticide-resistant mosquitoes as good vectors of plasmodium as susceptible ones? the drastic physiological changes that accompany the evolution of insecticide resistance may indeed alter the ability of vectors to transmit diseases, a possibility ...201021194433
plasmodium infection brings forward mosquito oviposition.invertebrate hosts often bring forward their reproductive effort in response to a parasitic infection. this is widely interpreted as a host-driven response aimed at compensating for the expected losses in future fitness as a result of parasitism. here we report that mosquitoes bring forward their oviposition schedule when they are infected with plasmodium, a parasite known to severely curtail mosquito fecundity. this response could aim at compensating for a negative time-dependent effect of the ...025788485
history of the discovery of the malaria parasites and their vectors.abstract: malaria is caused by infection with protozoan parasites belonging to the genus plasmodium transmitted by female anopheles species mosquitoes. our understanding of the malaria parasites begins in 1880 with the discovery of the parasites in the blood of malaria patients by alphonse laveran. the sexual stages in the blood were discovered by william maccallum in birds infected with a related haematozoan, haemoproteus columbae, in 1897 and the whole of the transmission cycle in culicine mos ...201020205846
plasmodium spp.: an experimental study on vertebrate host susceptibility to avian malaria.the interest in experimental studies on avian malaria caused by plasmodium species has increased recently due to the need of direct information about host-parasite interactions. numerous important issues (host susceptibility, development of infection, the resistance and tolerance to avian malaria) can be answered using experimental infections. however, specificity of genetically different lineages of malaria parasites and their isolates is largely unknown. this study reviews recent experimental ...201525450775
plasmodium relictum (lineage p-sgs1): further observation of effects on experimentally infected passeriform birds, with remarks on treatment with malarone.plasmodium relictum (lineage p-sgs1) is a widespread malaria parasite that causes disease of different severity in different species of birds. however, experimental studies on the effects of this parasite on avian hosts are uncommon. we investigated development of this lineage in experimentally infected greenfinches carduelis chloris and compared the obtained data with the literature information about the virulence of the same parasite lineage for phylogenetically closely related bird species. w ...200919545566
identification and characterization of the merozoite surface protein 1 (msp1) gene in a host-generalist avian malaria parasite, plasmodium relictum (lineages sgs1 and grw4) with the use of blood transcriptome.the merozoite surface protein 1 (msp1) is one of the most studied vaccine candidate genes in mammalian plasmodium spp. to have been used for investigations of epidemiology, population structures, and immunity to infections. however methodological difficulties have impeded the use of nuclear markers such as msp1 in plasmodium parasites causing avian malaria. data from an infection transcriptome of the host generalist avian malaria parasite plasmodium relictum was used to identify and characterize ...201324172200
changing climate and the altitudinal range of avian malaria in the hawaiian islands - an ongoing conservation crisis on the island of kaua'i.transmission of avian malaria in the hawaiian islands varies across altitudinal gradients and is greatest at elevations below 1500 m where both temperature and moisture are favorable for the sole mosquito vector, culex quinquefasciatus, and extrinsic sporogonic development of the parasite, plasmodium relictum. potential consequences of global warming on this system have been recognized for over a decade with concerns that increases in mean temperatures could lead to expansion of malaria into hab ...201424446093
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