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This study was conducted to investigate the Isosporoid protozoan infections in finch types. Fecal samples were collected from marketed domestic Java sparrows (Lonchura oryzivora), colored and white Zebra finch (Taeniopygia guttata), and European goldfinch (Carduelis carduelis) in southern Iran. The coccidial oocysts were recovered and investigated according to the morphological features and the ribosomal gene markers. Additionally, a challenge infection was conducted with 5 × 104 and 5 × 103 sporulated oocysts in four java sparrows to estimate the clinical manifestations. Based on the morphology, the oocysts of Isospora lunaris were identified in all sampled bird types; however, the molecular method revealed the isolates had considerable similarities with some of Isospora and systemic Isospora-like organisms named as Atoxoplasma. Phylogenetic data also constructed an Atoxoplasma/Isospora clade with high sequence identities. High dose of the challenge with the parasite led to severe depression and sudden death, but it did not coincide with remarkable lesions and parasitic invasion in visceral organs. Contrary to molecular results, this feature is consistent with the common Isospora infections in passerines and differs from those described for Atoxoplasma species. Because of the prevalence, possibility of transmission, and clinical consequences, preventive measures are necessary to avoid outbreaks of isosporoid infections among finch type birds.

The present study was conducted to investigate the prevalence and identification of most common parasitic infections of quails and to determine their seasonal variation. One hundred diseased quails (60 quails in summer and 40 quails in winter) were obtained from quail farms in different localities of Assiut and El-menia Governorates and were examined for the presence of ectoparasites, endoparasites, intestinal protozoa, blood protozoa and parasites of other organs (lungs, brain and liver). Results revealed that neither ectoparasites nor macroscopic parasites were observed in the examined quails. Mainly, the encountered parasites were intestinal protozoa (44%), blood protozoa (25%) and parasites of other organs (28%). The overall parasitic infection rate in the examined quails was higher in cold season (57%) than warm season (53%). The intestinal protozoa were identified including Eimeria spp. (30%), Cryptosporidium spp. (19%), Tetratrichomonas galinarum (15%), Cyclospora spp. (4%), Isospora spp. (3%) and Microsporidia spp. (3%). The prevalence rate of intestinal protozoal infection was higher in warm season 46.6% (28 out of 60 examined birds) than cold seasons 40% (16 out of 40 examined birds). The incidence rate of mixed intestinal protozoal infection was higher (24.8%) than the single infection (18.8%). The blood protozoa were reported including Leucocytozoon spp. (9%), Babesiosoma spp. (8%), Aegyptianella spp. (7%), Plasmodium gallinaceum (4%), Haemoproteus spp. (4%), Atoxoplasma spp. (1%) and Ehrlichia spp. (1%). The prevalence of parasitic infection in other organs showed that respiratory tract (trachea and lung) infection with Cryptosporidium spp. (24%), hepatic histomoniasis (3%) and brain toxoplasmosis (7%).

Between 1996 and 2013, 71 blue-crowned laughingthrush (Dryonastes courtoisi) chicks, a small passerine bird endemic to China, were born at Mulhouse Zoo in northeast France. None of them survived past 1 yr, and 82% died between 0 and 6 days old of an unidentified cause and despite an attempt to establish an artificial breeding protocol. Atoxoplasma spp., causing a disease known as systemic isosporosis, is a coccidian parasite that can infect several species of birds. Mulhouse's adult birds were suspected to be infected with Atoxoplasma spp. and to transmit this parasite to their offspring. A treatment with toltrazuril (Baycox® 2.5%) was implemented in the four adult birds. Coprologic examinations were performed before, during, and after the treatment to quantify the parasite load in feces. Polymerase chain reaction (PCR) assays were used to test blood samples from the adult and liver, lung, gizzard, and kidney samples from 10 chicks to detect Atoxoplasma spp. Five of the 10 chicks had some tissue samples positive for Atoxoplasma spp. in at least one of the three repeats of the atoxoplasmosis PCR. An average of 181 Isospora spp. oocysts per gram of feces were found in the group of adults before treatment. This number was reduced to zero 1 wk after the beginning of the toltrazuril treatment. The PCR results suggest a transovarian transmission of Atoxoplasma spp., but further investigation is needed for confirmation. The treatment with toltrazuril appears to allow a significant reduction of the parasite excretion.

Populations of green-winged saltators, Saltator similis, are decreasing especially because of illegal trade and infectious diseases. We describe natural cases of an extraintestinal isosporoid coccidian in caged S. similis, and suggest the need of preventive measures in handling these birds. Nonspecific clinical signs were seen in all of them, however, intracytoplasmic Atoxoplasma sp. was found in peripheral blood, reinforcing the idea of systemic isosporosis. Leukocytosis with high number of heterophils and monocytes suggested that atoxoplasmosis in green-winged saltators can progress as an acute disease. The birds showed clinical improvement after treatment. Handling recommendations were proposed to upgrade hygienic conditions of the facilities. We concluded that nonspecific symptoms and an acute inflammatory process can be associated with atoxoplasmosis in young S. similis. We emphasize the importance of blood smear to detect merozoites. RESUMO: As populações de trinca-ferro, Saltator similis, estão declinando especialmente em função do comércio illegal e das doenças infecciosas. Descrevem-se casos naturais de coccidiose extraintestinal em S. similis de cativeiro, sugerindo a necessidade de medidas preventivas no manejo desses animais. Sinais clínicos inespecíficos foram observados em todos os animais, contudo, formas intracitoplasmáticas de Atoxoplasma sp. foram vistas no sangue periférico, reforçando a ideia de isosporose sistêmica. Leucocitose com aumento de heterófilos e monócitos sugeriram que a atoxoplasmose em trinca-ferro pode progredir como uma doença aguda. As aves apresentaram melhora clínica após tratamento. Recomendações de manejo foram propostas a fim de melhorar as condições higiênicas das instalações das aves. Concluiu-se que sinais inespecíficos e processo inflamatório agudo podem ser associados com a atoxoplasmose em S. similis jovens. Enfatizamos a importância da avaliação do esfregaço sanguíneo para detector os merozoítos.

Based on a review of species mortalities, systemic Isospora species was identified as the primary cause of death in 22% (19 of 87) of blue-crowned laughing thrushes (BCLTs; Garrulax courtoisi) at the Jersey Zoo between 1997 and 2016. Fifty-eight percent of the affected birds were between 1 and 2 years old, and in 89% of cases, death occurred between August and December. Abnormal clinical findings in BCLTs with Isospora species infections included hepatomegaly and pectoral muscle myositis in 79% of the cases. The results of diagnostic blood testing in 90% of infected BCLTs 30 days before death were consistent with a severe leukocytosis with greater than 20% of mononuclear cells infected by merozoites. The most common lesions identified during gross necropsy examination were splenomegaly (100%), hepatomegaly (95%), and multifocal, raised, white foci in pectoral (84%) and heart (79%) muscle. Lymphohistiocytic inflammation was identified in the liver, heart, spleen, lung, striated muscle, and kidney tissue of birds with positive results for Isospora species. Merozoites were often observed in spleen, liver, pectoral muscle, and hearts of infected BCLTs. Polymerase chain reaction diagnostic testing that targeted the cytochrome c oxidase subunit, followed by Sanger sequencing, was used to confirm Isospora species in all 14 birds tested. Of samples tested, the highest genetic correlation was with GenBank accession number KT203397 (Isospora species JRB-2016 mitochondrion).

The parasite community associated with a population of eastern bluebirds (Sialia sialis) nesting in a grass- dominated habitat in northern Georgia, U.S.A., was surveyed by live examination of adults and nestlings; examination of feces, nesting materials, and blood smears; necropsy; and polymerase chain reaction techniques. During the course of 5 breeding seasons, we found 10 macroparasite species, which included 1 tick species (Ixodes brunneus), 1 louse species (Philopterus sialii), 1 species of hematophagous mite (Dermanyssus prognephilus), and 5 other species not previously reported from eastern bluebirds, including an acanthocephalan (Plagiorhynchus cylindraceus), a species of strongyloid nematode, a cestode (Hymenolepis sp.), a nestling bird fly (Carnus floridensis), and a nest mite (Campephilocoptes sp.); a description of feather mites associated with the population was not included in this report. Overall prevalence of macroparasites was 16.1%. We also detected 5 species of protistan parasites, including Haemoproteus fallisi, Plasmodium relictum, Trypanosoma avium, and 2 others, an Atoxoplasma sp. and a Sarcocystis sp., which represent new host-parasite records. One bird tested positive for West Nile virus and for St. Louis encephalitis virus. More than 50% of the birds examined were infected with 1 or more microparasites. Prevalence of microparasites varied by examination method employed. An updated list of known parasites of eastern bluebirds gathered from published literature and database searches is provided.

Summary A survey was carried out on the prevalence of blood parasites in birds in the Mascarene Islands. Smears from 357 birds of 25 species in 12 families were examined, of which 150 (42%) were found to harbour blood parasites. The most common parasites were Leucocytozoon; a new species, L. zosteropis, is described from the Grey White-eye Zosterops borbonica mauritiana. This parasite was observed in smears from 68 birds of three species: Z. borbonica, Z. chloronothos and Z. olivacea. Other species of Leucocytozoon identified were L. fringillinarum from fodies, sparrows and a bulbul and L. marchouxi from two doves. Haemoproteus was found only in domestic pigeons Columba livia and identified as H. columbae. Plasmodium relictum, P. vaughani and an unidentified species with elongate gametocytes were found in Zosterops, and Plasmodium sp. of low infection observed in other hosts. Trypanosoma mayae is redescribed from the House Sparrow Passer domesticus and the Mauritius Fody Foudia rubra, and considered to be a valid species. A new species of trypanosome, Trypanosoma phedinae, is described from the Malagasy Swallow Phedina b. borbonica. Other birds were found to harbour low infections of unidentified species of trypanosomes. A small number of birds were infected with Atoxoplasma, haemogregarines and Rickettsia-like organisms. An unidentified organism with a predilection for eosinophils was observed in several Mascarene Swiftlets Collocalia francica. The results are discussed in relation to the possible effects of the parasites on the birds of the Mascarene Islands and comparisons made with the results of similar surveys on other Indian Ocean Islands.

Prevalence and disease caused by isosporoid coccidia in passerine birds are well recognized, but confusion about the life cycles of the parasites has led to taxonomic inconsistencies. In this study, we characterized segments of the chromosomal small and large-subunit ribosomal RNA (rRNA) genes of coccidial parasites from 23 species of passerine birds, as well as heat shock protein 70, apicoplast rRNA, and chromosomal 5.8s rRNA genes from a subgroup of these animals, and we correlated genetic data with morphologic findings for different parasite developmental stages, host phylogeny, and overall taxonomic relations within the phylum Apicomplexa. Our findings indicate that isosporoid coccidia of passerine birds are monophyletic but exhibit substantial diversity, with most avian species having one or several unique parasite lineages that underwent synchronous speciation with their hosts, interrupted by sporadic episodes of lateral transmission across species and families. Molecular analyses support a homoxenous life cycle, with sexual forms occurring chiefly in the intestines and asexual merozoites present systemically. Rarely, extraintestinal sexual stages can occur. The passerine coccidia are genetically most closely related to species of Eimeria rather than Isospora. We suggest that these parasites, whether identified from blood merozoite stages or fecal oocysts, be provisionally grouped as a homogeneous clade of individual species in a single taxon and formally named when reliable criteria allowing reclassification of related genera in the suborder Eimeriina are clarified.

The intracellular hematozoa of vertebrates are apicomplexan parasites with a life cycle consisting of 3 major phases: schizogony (asexual), gametogony (sexual), and sporogony (asexual). Most members have heteroxenous life cycles, wherein gametogony and sporogony occur in an arthropod vector and schizogony occurs in the vertebrate host. Leucocytozoon toddi occurs in Falconiformes and Leucocytozoon ziemanni in Strigiformes. Considered nonpathogenic in adult raptors, Leucocytozoon can cause mortality in nestlings. Haemoproteus is generally considered nonpathogenic in raptors; however, there are recent reports of fatalities in owls. Plasmodium is the true malarial parasite of birds and mammals. One species, Plasmodium relictum, is considered pathogenic for raptors. Atoxoplasma (previously Lankesterella) is an avian coccidian with both blood and intestinal stages. Babesia has been reported in raptors and might cause anemia and blindness in young falcons. In this article, advances in hematozoon diagnos...

One-hundred 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 overall prevalence of infection was 47.8%. Prevalences of Haemoproteus spp. (27.2%), Plasmodium spp. (25.0%), Leucocytozoon spp. (8.9%), Atoxoplasma spp. (4.4%), Trypanosoma spp. (1.1%), and microfilariae (0.6%) were recorded. No differences were discernible in parasite fauna or intensities of infection between males and females or between different subspecies. However, prevalence of infection of Haemoproteus, Leucocytozoon, and Plasmodium spp. was different in different host subspecies. These differences can be explained by differences in geographical location of breeding areas of these birds.

A new species of isosporan (Apicomplexa: Eimeriidae) is reported from the Bali mynah Leucopsar rothschildi (Passeriformes: Sturnidae). Oöcysts of Isospora rothschildi n. sp. are spherical to subspherical, 22.3 x 21.6 (20-26 x 19-23) microm, with a shape index (length/width) of 1.03 (1.00-1.15). A micropyle and oöcyst residuum are absent, but one to many polar granules are present. Sporocysts are ovoidal, 15.9 x 10.6 (15-18 x 9.5-11) microm, with Stieda and substieda bodies and a shape index of 1.50 (1.39-1.65). Each sporocyst contains an ellipsoidal sporocyst residuum, 8.0 x 5.8 (6-11 x 5-8), and each sporozoite contains two refractile bodies. No correlation was found between the presence of coccidian oöcysts in the faeces of some of the birds and Atoxoplasma in blood smears.

The provision of supplementary food for wild birds in gardens during the winter months is common in the UK, but it is possible that it may precipitate infectious diseases in the birds. This paper describes the results of postmortem examinations of 116 wild finches carried out over a period of four years. The two commonest causes of death in areas where high mortality had been reported were infections with the bacteria Salmonella typhimurium DT4o and Escherichia coli O86. Coccidia of the genera Atoxoplasma or Isospora were found in several of the birds but were considered to be incidental. Megabacteria were also identified in some of the birds, for the first time in flocks of wild birds in the UK, but they were not considered to be significant.

Coccidian parasites are protozoans in the subphylum Apicomplexa , class Sporozoa , which have a characteristic apical complex of organelles in the infective stages that enable the parasites to enter host cells. These intracellular organisms cause a myriad of diseases in avian species by destroying the cells they invade. For the clinician, some of these parasites can present an antemortem diagnostic challenge owing to the variety of bird species and organ systems affected; therefore, instituting an effective treatment regimen can be an additional hurdle. This article reviews the following coccidian parasites of nondomestic avian species: Eimeria, Isospora, Caryospora, Cryptosporidium, Atoxoplasma, Sarcocystis , and Toxoplasma . Life cycles, clinical signs, diagnostic tests, prevention, and treatment are discussed.

The major hemoprotozoa of caged and aviary birds, primarily psittacines and passerines, are reviewed: Plasmodium, Hemoproteus, Leucocytozoon, Atoxoplasma, Trypanosoma, Aegyptianella, Babesia , and Akiba . The occurrence, life cycles, species affected, vectors involved, methods of diagnosis of infection, and some suggested treatment and preventative measures are presented.

A young goldfinch submitted for necropsy was found to have pale yellow enlarged liver diffusely spotted by petechial haemorrhages. Histologically, hepatitis associated with the presence of karyomegalic cells was the main finding observed. Electron microscopy revealed the presence of papovavirus-like particles in the karyomegalic nuclei. Moreover, numerous atoxoplasma were observed by electron microscopy in the cytoplasm of mononuclear cells infiltrating the liver.

House sparrows (Passer domesticus biblicus Hartert, 1904) caught in the Jordan valley, the coastal plain, and the desert region in Southern Israel were found massively infected with extraintestinal proliferative stages of Isospora, previously named Atoxoplasma. Infection coincided with Isospora spp. infections in the digestive tract. Prevalence of infection reached 70% among sparrows of all three regions; however, only in the Jordan valley did the severity of the sparrows compromised their survival. Healthy appearing captured birds showed symptoms of "going light" syndrome -- diarrhea, emaciation, and death. Birds succumbed within 48 h to 15 days after confinement to cages. Merozoites accumulated predominantly in the spleen but were rarely found in the peripheral blood. The parasite stages in the visceral leukocytes propagated by merogony and yielded single large waiting-stage merozoites. Visceral infections resulted in multifocal necrosis. Proliferative visceral Isospora infection (atoxoplasmosis) is one of the more severe causes of mortality among captive birds, free-ranging birds appear to coexist with the infection but succumb under capture stress.

Clinical signs, histopathological and ultrastructural findings associated with Atoxoplasma spp. natural infection in captive canaries (Serinus canaria) are described. Intracytoplasmic Atoxoplasma-like protozoa were found in the liver and lung. In the liver, protozoa were found in hepatocytes and Kupffer's cells and were associated with granulomatous hepatitis and a marked bile duct hyperplasia. An usual finding was the presence of infected mononuclear cells adhered to the endothelium of the blood vessels in lung. The diagnosis was confirmed by ultrastructural examination of reprocessed paraffin-embedded tissues.

Atoxoplasma spp. (extraintestinal Isospora spp.) are coccidian parasites that infect a variety of passerine species. Atoxoplasmosis has been difficult to diagnose using buffy coat and organ impression smear examinations or histopathologic examination of tissues at necropsy. The prevalence of this parasite was studied in the tanager collection of a zoological park after the death of several tanagers from confirmed and suspected infections. A polymerase chain reaction assay was used to test blood, feces, or tissue samples (or all) from 88 individuals representing 18 species. Twenty-three of 60 (38.3%) blood samples from clinically healthy birds tested positive for Atoxoplasma, and one of six fecal samples was positive. Nineteen of 32 (59.4%) tissue samples from deceased tanagers tested positive. A total of 57 other institutions were also queried regarding the presence of Atoxoplasma. The high number of Atoxoplasma-positive clinically healthy birds suggests that the parasite is prevalent subclinically within tanager collections, with young birds and stressed adults being the most likely to develop clinical disease. Thorough disinfection of enclosures, consideration of enclosure designs, and preventing fecal contamination of food and water are important methods of decreasing transmission. Selective breeding programs and regular screening of breeding pairs may be recommended to decrease transmission to susceptible offspring. Care should also be taken when housing tanagers in mixed species or in outdoor enclosures because the transmission risks between species have not been well established.

A hybrid passerine (Serinus canarius xCarduelis cannabina) in poor bodily condition was presented for consultation but died during clinical examination. Examination of the faeces revealed the presence of oocysts that were assigned to those of Isospora serini species. The sexual stages of the parasite were found in the intestinal tract. Also, merozoites of an Atoxoplasma (Syn. Lankesterella)-like parasite were detected in mononuclear cells in cardiac blood. These findings indicate a coccidiosis pattern consistent with atoxoplasmosis.

Birds from three National Parks (Bwindi Impenetrable, Kibale, and Queen Elizabeth) in western Uganda were surveyed during the dry season in July 2003 and investigated for hematozoa by microscopic examination of stained blood films. Of 307 birds examined, representing 68 species of 15 families and four orders, 61.9% were found to be infected with blood parasites. Species of Haemoproteus (15.3% prevalence), Plasmodium (20.5%), Leucocytozoon (40.1%), Trypanosoma (11.4%), Hepatozoon (2.6%), Atoxoplasma (0.3%), and microfilariae (3.9%) were recorded. Except for Haemoproteus spp. infections, the overall prevalence of hematozoa belonging to all genera was significantly higher in this study than was previously reported in Uganda. Thirty-six species of birds were examined for blood parasites for the first time and 112 new host-parasite associations were identified. Eighty-one were at the generic and 31 at the specific level of the hematozoa. Hepatozoon and Atoxoplasma spp. were detected for the first time in Uganda.

Molecular and morphological data permit a rational subdivision of the paraphyletic Isospora into 2 apparently monophyletic groups of parasites, i.e., Isospora and Cystoisospora. Atoxoplasma was determined to be a junior objective synonym for Isospora. Tetrasporozoic, diplosporocystic oocysts possessing Stieda bodies in their sporocysts belong to Isospora (Eimeriidae) and have been described principally from the feces of birds. Tetrasporozoic, diplosporocystic oocysts without Stieda bodies in their sporocysts belong to Cystoisospora (Sarcocystidae).

In June 1993 an unusual coccidian parasite was identified in lung tissue from a northern cardinal (Cardinalis cardinalis), collected near Tucson, Arizona (USA), which died in respiratory distress. Histologically, there was evidence of severe, generalized interstitial pneumonia, associated with the parasite. Both asexual and sexual stages were seen. Schizonts, gamonts, and sporulated oocysts were seen in lung tissue. The parasite most closely resembled coccidia of the genus Lankesterella. This is the first report of such a coccidian parasite in the alveolar tissue of a cardinal.

Summary Staphylococcus aureus was isolated from six cases of bacterial infection in canaries, Staphylococcus hyicus from three and Staphylococcus intermedius from one case. Staphylococcus aureus was most often involved in outbreaks of septicaemia, with or without ‘Megabacterium’ proventriculitis. The other coccal species were mainly complicating disease caused by Atoxoplasma (Lankesterella), Chlamydia psittaci and canary pox.

Transmural lymphocytic enteritis was diagnosed in thirteen Nashville warblers (Vermivora ruficapilla) during an epornitic with high mortality. In the intestinal lesions, asexual stages of coccidia were present within lymphocytes and asexual and sexual stages of coccidia were present within intestinal villar epithelium. Ultrastructurally, the infiltrating lymphocytes resembled granular ("intraepithelial") lymphocytes, a cell known to be important in the life cycle of some avian coccidia. Gross and histopathologic features of this enteritis resemble intestinal changes described for Isospora/Atoxoplasma spp. in other passeriformes and lymphoproliferative disease in gold-finches.

Introduced avian diseases pose a significant threat to forest birds on isolated island archipelagos, especially where most passerines are endemic and many groups of blood-sucking arthropods are either absent or only recently introduced. We conducted a blood parasite survey of forest birds from the main islands of American Samoa to obtain baseline information about the identity, distribution and prevalence of hematozoan parasites in this island group. We examined Giemsa-stained blood smears from 857 individual birds representing 20 species on Tutuila, Ofu, Olosega, and Ta'u islands. Four hematozoan parasites were identified ? Plasmodium circumflexum (1%, 12/857), Trypanosoma avium (4%,32/857), microfilaria (9%, 76/857), and an Atoxoplasma sp. {

There is little published information on the pathogens present in New Zealand passerines. We report here on a preliminary survey of selected pathogens and haematology profiles for seven species in the Auckland region. Avian translocations are commonly used for the recovery of threatened species. Translocations may increase the risk of spreading disease to immunologically na�ve populations. It is therefore important to take every opportuntty to gather baseline disease data and test hypotheses associated with disease. Blood, cloacal and faecal samples were collected from Fernbird Bowdleria punctata, Tui Prosthemadera novaeseelandiae, Bellbird Anthornis melanura, Tomtit Petroica macrocephala, New Zealand Robin Petroica australis, Whitehead Mohua albicilla and Starling Sturnus vulgaris during four translocations to and from Tiritiri Matangi Island. Birds (n = 137) were also examined for external lesions typical of avian pox. Blood samples (n = 40) were screened by microscopy for Plasmodium spp., Atoxoplasma spp. and other blood parasites and a differential white blood cell count was made. Cloacal swabs (n = 38) were cultured for Yersinia spp., Salmonella spp. and Campyobaeter spp. Faecal samples were screened for coccidia spp. (n = 28). An unidentified coccidian sp. and a Haemoproteus sp. were detected in one Fembird and one robin respectively. No other organisms with the potential to cause disease were detected. Despite the effort required to complete disease screening, we argue that disease samples and baseline haematology normal values should be collected at an opportunities. We make recommendations for future disease screening, and discuss the importance and potential significance of disease to the conservation of New Zealand's biodiversity.

Extract Juvenile hihi or stitchbirds (Notiomystis cincta) and saddlebacks (Philestumus carunculatus) are particularly prone to systemic protozoal infections when kept in high density populations. Granu-lomatous lesions in the intestine, liver and spleen are associated with proliferating intracellular schizonts. Affected birds become anorexic and lose weight or die suddenly without clinical signs. The protozoan in hihi appears most likely to be Atoxoplasma spp whereas that in saddlebacks is more like Plasmodium spp.

Merozoites of an Atoxoplasma species were present within parasitophorous vacuoles in the cytoplasm of leucocytes in the blood vessels in the small intestine of the greenfinch (Carduelis chloris). The merozoites indented the nucleus of the leucocytes. Merozoites, macrogametes, and microgamonts were present in the epithelial cells of the intestines. No merogony was observed. Experiments provided circumstantial evidence linking disporocystid-octozoic oocysts with the blood and intestinal infections.

A total of 641 birds representing 135 species of 25 families from Noel Kempff Mercado National Park in west-central Bolivia was examined for hematozoa; only 33 (5.1%) harbored blood parasites. Microfilariae were the most commonly encountered hematozoans, followed, in numerical sequence, by species of Haemoproteus and Plasmodium; Trypanosoma, Atoxoplasma, and Hepatozoon were seen infrequently. The survey included 13 new host-parasite records, and 58 species of birds were examined for blood parasites for the first time; 43 were parasite-free. The low prevalence of parasitism recorded in this survey is compared to other areas in the Neotropical region and to prevalence of blood parasites in the avifauna of other major land masses.

SYNOPSIS. Oocysts of Isospora serini and Isospora canaria. from the canary Serinus canarius. were broken. added to a cell suspension, fixed in Karnovsky's fluid, and studied in the electron microscope. The oocyst wall of each species had an electron_ lucent inner layer, a more osmiophilic middle layer and an outer layer of electron-lucent (I. serini) or electron-dense material interspersed with some electron-lucent material (1. canaria). A few, relatively large lipid-like bodies were present in the outer or middle layer of the oocyst wall of I. canaria. As many as 9 membranes were present in the oocyst wall of I. canaria and 3 in that of I. serini. When exposed to a trypsin-sodium taurocholate fluid, sporozoites of I. serini excysted from 5-month-old sporocysts in vitro, but not from sporocysts stored for more than 6 months. No excystation occurred in l5-month-old I. canaria sporocysts. Similarities and differences in excystation between I. serini and other Isospora, Eimeria, and Sarcocystis species are discussed. R ECENTL Y, Box (1) dt'scrihed the exogenous stages of Iso­ s para serini (Aragao, 1933), which may be synonymous with Atoxoplasma, and Isospora canaria Box, 1975, from canaries, Serinus canarius Linnaeus. When examined in the light micro­ scope the sporulated oocysts of these species are very similar structurally and differ only slightly in size. Our electron-micro­ scopic findings with regard to the similarities and differences of the oocyst walls of I. serini and I. canaria, as well as light­ microscopic observations on excystation of I. serini, are described herein.

Summary A survey of the literature published between 1890–1978 on the avian haematozoa of Western Europe has shown that 15 000 birds representing 225 species, 132 genera and 44 families were examined. 4356 birds were infected with one or more parasites of the genera Haemoproteus, Leucocytozoon, Plasmodium, Trypanosoma, Toxoplasma, Atoxoplasma (Lankesterella), Hepatozoon and Babesia. An annotated host-parasite check-list is presented which shows the regional distribution of the parasites recorded for each species of bird. Tables are given indicating the total numbers of birds for each species examined, those infected with each parasite genus and the overall totals for individual countries. These are discussed in relation to regional differences in numbers of birds examined and prevalence of individual parasite groups. Brief mention is made of the relationship between trans-Saharan migrants and their parasites.

A total of 8170 birds of 153 species, representing 41 families, from Maryland and New Jersey, were examined for blood parasites. Eighty-eight species were sampled in New Jersey and 128 in Maryland; 63 species were common to both areas. Ten percent (833) of the birds harbored one or more parasite species of the following genera: Haemoproteus (4.3%), Leucocytozoon (3.9%), Plasmodium (1.9%), Trypanosoma (0.3%), Lankesterella (=Atoxoplasma) (0.04%), and unidentified microfilariae (0.3%). Prevalences from both areas were similar, but were markedly lower than previously recorded. The coefficient of community, an ecological measure of similarity, was applied to both bird and parasite faunas within the two study areas, and indicated that because of the high degree of specificity of parasites to their hosts only birds shared by the two samples had the same parasites. This measure also revealed the absolute necessity of using only similar taxa in any comparison of hematozoan prevalence in different avifaunas in different geographic regions.The Maryland sample was unique in that it allowed a comparison of prevalences over a 30-year period, revealing that years with larger samples generally exhibited a uniform geographic prevalence. The New Jersey sample was obtained from different topographic regions; the results confirm the concept that prevalence of hematozoa is correlated with regional topography, even in areas closely juxtaposed.

Summary The results of a four year study of haematozoa in Palaearctic migrants, particularly Phylloscopus trochilus, at Tring are reported. Of 379 P. trochilus examined 11·3% were infected. Haemoproteus and Leucotytozoon were observed in adult birds returning in the spring and Atoxoplasma was the only parasite occurring in juvenile birds. Observations on re-trapped birds showed that patency quickly diminished into a latent phase and emphasized further the importance of migration in acquiring most haematozoan parasites.

SYNOPSIS. All of 99 adult English house-sparrows, examined in the St. Albans area of Hertfordshire, England, were found to be infected with the organism previously defined by Garnham (1950) as Atoxoplasma. Young birds were found to become infected while still in the nests and as early as 6 days after hatching; there was no evidence to suggest that the parasite was transmitted through the egg. Within a few weeks of leaving the nests, all of 150 fledgling sparrows examined were heavily infected and several trapped birds died from massive infections. All stages of schizogony were found in the lymphoid-macrophage cells of the spleen, bone marrow and liver of these birds; later, as the schizogonic cycle abated, gametocytes developed in similar cells of the liver, lungs and kidney. These gametocytes are of the Eimeria type: the zygote nucleus divides to produce an asporous and polyzoic oocyst containing a large number of sporozoites, and after the rupture of the oocyst these sporozoites invade the lymphocytes and monocytes of the peripheral blood. Transmission of the parasite in the sparrow is thought to take place after the ingestion of infected mites (Dermanyssus gallinae) by the young birds in the nests: unchanged sporozoites were found in smears of these mites that had been fed on infected sparrows. Transmission experiments were impossible due to the complete lack of clean sparrows. The taxonomic status of Atoxoplasma is discussed. The type of life cycle and the production of asporous, polyzoic oocysts indicate inclusion of this parasite in the Order Coccidiida, Family Eimeriidae, Sub-Family Cryptosporidiinae Hoare, 1933. After comparison of the two genera, the author concludes that Atoxoplasma must be regarded as a synonym for Lankesterella. Some previously described species of Atoxoplasma are, therefore, transferred to the genus Lankesterella. The name Lankesterella garnhami nov. sp., is proposed for the parasite in the English sparrow (Passer domesticus domesticus), and Lankesterella serini nov. sp., for that in the canary (Serinus canarius).

During 1966–69 mortality attributed to Lankesterella infections occurred among evening grosbeaks (Hesperiphona vespertina) in Algonquin Park, Ontario. Peak mortality was recorded between mid-June and mid-July in all four years, being highest in 1967. The parasite was subsequently discovered in wild rose-breasted grosbeaks (Pheucticus ludovicianus) and was artificially transmitted to other passerines (though not to a duck) by inoculating infected tissues. Mites from two infected grosbeaks failed to initiate infections when fed to uninfected birds, Isospora oocysts from the feces of grosbeaks were not infective to canaries. The ultrastructure of the parasite in grosbeaks is similar to other eimeriid coccidia. The generic nature of this parasite is discussed in light of recent reports that the species of Lankesterella (= Atoxoplasma) in house sparrows might really be referable to Isospora.

1. The following new species were encountered in this investigation:Haemogregarina hamata in Lacerta jacksoni;Hepatozoon minchini in Crotaphopeltis degeniPirhaemocyton granosa in Agama colonorumAtoxoplasma argyae n.gen. n.sp. in Argya rubi-ginosaSpirochaeta harveyi in Cercopithecus aethiops.2. Further information is given in regard to the following known species, including new host records:Plasmodium pitmani in Mabuia striata and M. maculilabrisTrypanosoma martini in Mabuia maculilabrisPlasmodium vaughani in Othyphantes reichenowiPlasmodium relictum in Othyphantes reichenowi and Passer iagoensisHaemoproteus wenyoni in Passer griseusLeucocytozoon sp. in nine species of birdsHepatocystes epomophori in Epomophorus labiatusHepatocystes kochi in Cercopithecus, etc.Babesia pitheci in Cercopithecus mitis.3. Exo-erythrocytic schizogony is described in Plasmodium pitmani of the skink (from spleen and heart preparations).

SYNOPSIS Coccidia-free and mite-free domestic canaries Serinus canarius given sporulated Isospora oocysts of canary origin and autopsied at intervals thereafter had numerous organisms in cells of the macrophage system structurally similar to organisms called Atoxoplasma. Judging from the sequence of intensity of infection, the mucosa of the upper intestine was parasitized first and the organisms spread from there down the intestine and to the internal organs. The prepatent period of 10 days for the Isospora infection could be started in one bird by oocyst administration and completed by transfer of infected liver cells from this bird to a 2nd bird. Isospara oocysts from sparrows were not infective for a canary.

Toxoplasma-like avian parasites inhabiting mononuclear phagocytes have been called Haemogregarina, Toxoplasma. avian Toxoplasma, Atoxoplasma, and Lankesterella by various authors. My attempts to transmit the parasites by bloodsucking mites or by transfer of blood and tissues of infected sparrows and canaries were unsuccessful. However, it was noted that the infection was exacerbated under conditions that favored transmission of coccidiosis: crowding and lack of cleanliness. Oral inoculation of sporulated oocysts of Isospora resulted in death from overwhelming macrophage infection with Toxoplasma-like organisms. Experiments using sparrows and canaries showed that the Isospora species involved was not cross infectious. Further investigations using canaries demonstrated that after oral oocyst inoculation, infection of macrophages spread from the submucosa of the duodenum to the liver. spleen, and lungs. After several generations in the internal organs, asexual multiplication, occured in the intestinal epithelium of the small intestinc. Fecal oocysts first appeared at the end of 9–10 days. Oocysts continued to be passed in the feces for months after infection. This chronicity may be explained by the relatively long life of the macrophages that serve as host cells for the asexual stages as compared to the intestinal epithelium which is the cell type parasitized by conventional coccidia.

SYNOPSIS. Large numbers of birds, until recently, were brought into the United States each year. Countries of origin were varied, and included those of Australasia, Africa, South America, and the Caribbean Islands, as well as other places. With them of course come their parasites, some of which may be potential pathogens to domestic avifauna. In part for this reason, a survey was undertaken of blood parasites of birds from pet shops and importers. So far a total of 1234 birds belonging to 186 species has been examined. Several new species and subspecies of avian Plasmodium have been found in the course of this study, including P. octamerium Manwell, 1968 in a Pintail Whydah, Vidua macoura, from Africa; P. paranucleophilum Manwell & Sessler, 1971 in a South American tanager, Tachyphonus sp.; and P. nucleophilum toucani Manwell & Sessler 1971 in a Swainson's Toucan, Ramphastos s. swainsonii. Plasmodium huffi Muniz, Soares & Battista is undoubtedly a synonym pro parte for the last. Plasmodium tenue Laveran & Marullaz, long thought to be a synonym of Plasmodium vaughani Novy & MacNeal, was rediscovered and found to be a valid species. Plasmodium nucleophilum, infrequently seen in the New World, occurred in many Asian and African birds, and especially in starlings. Infections with other species of Plasmodium were common. Haemoproteus was the commonest blood parasite; Leucocytozoon was very rare as was Atoxoplasma (Lankesterella). The 2 families of birds best represented were the Fringillidae and the Psittacidae, but no blood parasites were seen in the latter. It is clear that imported birds are often infected with blood protozoa, some of which are unknown from native birds.

Progress in the understanding of the sporozoa stemmed from new concepts and new measurements, often using refined techniques. New concepts developed from linking knowledge about the cyst-related transmission of Toxoplasma to oocyst-related transmission of the coccidia. It is now apparent that both oocyst and tissue cyst transmission occur in Toxoplasma, Sarcocystis, Hammondia n.g., Isospora and perhaps Atoxoplasma. It is likely that we know the complete cycles of Toxoplasma and Sarcocystis and some progress has been made towards understanding those of Besnoitia and Frenkelia. Our present knowledge is sufficient to propose a new classification of some of the higher coccidia (Table 5), and to devise keys for the determination of cysts and oocysts (Tables 2, 4). Additional terminology is listed (Table 1).