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Protozoa of the genus Sarcocystis are obligatory heterogenous parasites with both definitive and intermediate hosts. Opossums (Didelphis aurita) can shed multiple species of Sarcocystis with birds as the intermediate host. The pathologies of Sarcocystis species in birds have not been thoroughly elucidated. Therefore, the aim of the present study to determine the main lesions that can occur in acute and chronic infections in intermediate hosts, when they ingest infective sporocysts that are shed in the opossum's feces, using budgerigars as a model. To this end, 12 budgerigars, Melopsittacus undulatus, were divided into two groups that received an inoculum with 60 and 120 sporocysts. Birds that died or were euthanized were necropsied, and the lung, tongue, liver, brain, heart, and skeletal striated muscles were collected and fixed in 10% formalin for histopathological analysis. The infectivity varied according to the sample and infective dose. Acute histopathological lesions were characterized by evidence of slightly degenerated hepatocyte cords that permeated the region of the blood vessel and hepatic sinusoids. Pulmonary tissue lesions were also observed in the parabronchial region with the presence of inflammatory infiltrates associated with areas of edema and atelectasis. In chronic infections, few mature cysts were observed in the chest, and many mature cysts in the thigh and tongue muscles. Thus, it was possible to conclude that lesions are highly characteristic in acute infection and, in chronic infections, cysts were present but without major lesions. In this case, the preferred organs of parasitism were the thigh and the tongue.

Outbreaks of avian trichomonosis are being reported worldwide; meanwhile, the genetic and virulence variations are under investigation. In this study, the occurrence and genetic variability of oral or faecal trichomonads among various avian species were investigated. Samples obtained from either the oropharyngeal cavity, crop/oesophagus, droppings/cloaca, or conjunctival swabs of avian species were inspected for flagellates. Phylogenetic analysis of partial ITS1-5.8s rRNA-ITS2 sequences from selected samples was performed to investigate the genetic diversity of the isolates. Investigation of 737 birds revealed an infection rate of 15.7% in the upper gastrointestinal tract, 7.3% in the faecal samples, and 0.7% involvement of the conjunctiva. Phylogenetic analysis of partial ITS1-5.8s rRNA-ITS2 sequences from selected samples, identified genotypes A and B of Trichomonas gallinae and genogroups A-C and E of Tetratrichomonas gallinarum . A novel ITS genotype of intestinal trichomonads was also detected in hooded crow ( Corvus cornix ) and common mynah ( Acridotheres tristis ). In the present study, in addition to Columbiformes and Falconiformes, trichomonads were detected in Passeriformes and Galliformes with the involvement of organs other than the gastrointestinal tract. Genotype A T. gallinae was detected in domestic pigeons ( Columba livia domestica ), a laughing dove ( Spilopelia senegalensis ), a common kestrel ( Falco tinnunculus ), a budgerigar ( Melopsittacus undulates ), and a canary ( Serinus canaria ). Distinct genotype B was detected in a common mynah and a budgerigar. Genogroups A-C of T. gallinarum were also demonstrated in Galliformes and Anseriformes. Furthermore, two novel trichomonad ITS genotypes were detected in hooded crows and a common mynah warranting detailed multi-locus molecular analysis. RESEARCH HIGHLIGHTS ITS diversity of trichomonads was shown in various avian species.Diversity of the parasites' target organ and clinical manifestations was demonstrated.Two novel ITS genotype trichomonads from common mynah and hooded crow were identified.

This study was conducted to identify the Sarcocystis species that infect the opossum Didelphis aurita in order to determine which sporocysts they are excreating in to the environment and help determine the role of D. aurita in the epidemiology of Sarcocystis. Sporocysts were obtained from intestinal tracts of 8 of 13 D. aurita trapped in Rio de Janeiro state, Brazil, and were orally inoculated into Melopsittacus undulatus and Balb/c nude Mus musculus. Portions of organs and muscles were processed for histology, immunohistochemistry, transmission electron microscopy (TEM), and PCR using primers JNB 33/54, and ITS. Amplification products were subjected to RFLP using DraI and HinfI. Some birds were euthanized 6, 7, 13, 16, and 24 days after inoculation (DAI). All other birds and all mice were euthanized 60 DAI. Schizonts were observed in the lungs using histology and immunostaining in birds examined prior to 60 DAI. Sarcocysts with a ~ 1.5-μm-thick wall were found in the breast, thigh, and tongue of some birds. Sarcocystis asexual stages were isolated in cell cultures inoculated with sporozoites. Parasite DNA isolated from bird tissues and cell cultures demonstrated that S. falcatula-like parasites were present in all samples derived from positive opossums. Asexual stages molecularly characterized as S. lindsayi-like were isolated in cell culture from one opossum with an apparent multiple infection. This study demonstrated that D. aurita is a definitive host for S. falcatula-like parasites and indicates that S. lindsayi-like parasites can be found in coinfections of this opossum species.

The morphological, biological, and molecular characteristics of Cryptosporidium avian genotype V are described, and the species name Cryptosporidium avium is proposed to reflect its specificity for birds under natural and experimental conditions. Oocysts of C. avium measured 5.30-6.90 μm (mean = 6.26 μm) × 4.30-5.50 μm (mean = 4.86 μm) with a length to width ratio of 1.29 (1.14-1.47). Oocysts of C. avium obtained from four naturally infected red-crowned parakeets (Cyanoramphus novaezealandiae) were infectious for 6-month-old budgerigars (Melopsittacus undulatus) and hens (Gallus gallus f. domestica). The prepatent periods in both susceptible bird species was 11 days postinfection (DPI). The infection intensity of C. avium in budgerigars and hens was low, with a maximum intensity of 5000 oocysts per gram of feces. Oocysts of C. avium were microscopically detected at only 12-16 DPI in hens and 12 DPI in budgerigars, while PCR analyses revealed the presence of specific DNA in fecal samples from 11 to 30 DPI (the conclusion of the experiment). Cryptosporidium avium was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus). Naturally or experimentally infected birds showed no clinical signs of cryptosporidiosis, and no pathology was detected. Developmental stages of C. avium were detected in the ileum and cecum using scanning electron microscopy. Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. avium is genetically distinct from previously described Cryptosporidium species.

Nine opossums, Didelphis aurita , were captured in the city of Seropédica, State of Rio de Janeiro, Brazil and examined for species of Sarcocystis. Sporocysts were observed in the mucosal scrapings of the small intestine from 3 opossums. Five budgerigars, Melopsittacus undulatus , were infected with sporocysts from each of these infected opossums and 5 budgerigars were used as controls. Of the 15 sporocyst-treated budgerigars, 5 birds that received sporocysts from 1 of the infected opossums developed tissue parasites. Meronts in the vascular endothelium of the lung venous capillaries and cysts in the skeletal and cardiac muscle cells were observed in histological sections stained with hematoxylin and eosin. The microscopic cysts, which were predominantly in the tongue and leg muscles, ranged from 65.3 to 118.1 μm in length and 14.0 to 29.4 μm in width and from 0.9 to 1.9 μm in thickness of the cystic wall. Sections examined by transmission electron microscopy revealed that the cyst wall contained numerous slender and jagged-shaped protrusions, each with a finger-like formation at the end. The morphology, especially of the cyst wall, and the morphometry of the tissue cysts indicate that the parasite is Sarcocystis lindsayi and, therefore, the opossum, D. aurita , is now considered a definitive host for this species in Brazil.

Trichomonas gallinae is a flagellated protozoon which parasitizes in the upper digestive tract of different birds, especially columbiformes (doves and pigeons) and falconiformes. The parasite is also a common inhabitant of the crop of psittacine birds and is frequently detected in budgerigars. The lesions associated with T. gallinae infection of the upper digestive tract range from mild inflammation of the mucosa to large caseous lesions that block the lumen of the oesophagus. Nitroimidazoles are considered to be the drugs of choice for the treatment of trichomonosis. However, only a few studies report the existence of resistant strains of T. gallinae to these drugs. Thus, in the present investigation cloned cultures of T. gallinae obtained from budgerigars and pigeons were analysed for the first time for their in vitro susceptibilities against four 5´-nitroimidazole derivates, including metronidazole, dimetridazole, ronidazole and ornidazole. Significantly different minimal lethal concentrations (MLCs) were observed for them against all four drugs. The lowest MLCs revealed the Trichomonas isolates obtained from two budgerigars, ranging from 2.0 ± 0.3 to 3.0 ± 0.7 μg/ml for metronidazole and dimetridazole, and from 2.0 ± 0.6 to 6.7 ± 1.7 μg/ml for ornidazole and ronidazole. Contrary to this, the highest MLCs were recorded for one Trichomonas isolate obtained from a pigeon, ranging from 83.3 ± 6.7 (for dimetridazole and ronidazole) to 103.3 ± 3.3 μg/ml (for metronidazole and ornidazole). The data obtained for the resistance testing were further compared with already available genetic data of the small subunit rRNA gene sequences and ITS-1, 5.8S rRNA and ITS-2 sequences, indicating a certain correlation between in vitro results and strain relationships., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Objective: This study was carried out to detect chewing-lice found on some birds in Turkey., Methods: For this aim, a Eurasian collared dove (Streptopelia decaocto), a budgerigar (Melopsittacus undulatus) and a marbled duck (Marmaronetta angustirostris) were examined for the louse., Results: Columbicola bacillus (Giebel, 1866) was found on a Eurasian collared dove (Streptopelia decaocto), Afrimenopon waar (Eichler, 1947) on a budgerigar (Melopsittacus undulatus) and Anatoecus icterodes (Nitzsch, 1818) on a marbled duck (Marmaronetta angustirostris)., Conclusion: All three louse species were recorded for the first time in Turkey. Anatoecus icterodes was reported for the first time from marbled duck in the worldwide. Therefore, marbled duck is a new host for Anatoecus icterodes.

The trophozoites of Trichomonas gallinae and Tetratrichomonas gallinarum were studied by means of light and electron microscopy after cloning and cultivating them axenically. T. gallinae trophozoites varied in shape reaching from ovoidal to pyriform and had a size of about 7-11 microm. They were provided with four free flagella and a fifth recurrent one, which did not become free at the posterior pole. The nucleus was ovoid, had a size of about 2.5-3 microm, and was situated closely below the basal bodies of the flagella. The axostyle consisted of a row of microtubules running from the region of the apical basal bodies to the posterior end of the cell. In addition to flagellated stages, which contained food vacuoles, hydrogenosomes, a costa-like structure, and glycogen granules besides lacunes of endoplasmic reticulum, spherical, nonflagellated, and cyst-like stages occurred. The trophozoites of T. gallinarum appeared mostly pear-shaped and ranged in size from 6 to 15 microm. They had also four free anterior flagella and a fifth recurrent one, which became free at the posterior pole in contrast to that of T. gallinae. Another clearly visible difference to T. gallinae was the occurrence of a sphere of lacunes of the endoplasmic reticulum surrounding in a regular distance the nucleus with its typical perinuclear membranes. Furthermore, the food vacuoles appeared very large. However, both species clearly differed from the trophozoites of Histomonas meleagridis.

Sporocysts of Sarcocystis were obtained from intestinal scrapings of three out of five opossums (Didelphis aurita) trapped in the southeastern region, of the State of Rio de Janeiro, Brazil. Fifteen caged budgerigars (Melopsittacus undulatus) received, orally, twenty-six sporocysts in 500 mL PBS, but only five belonging to one of the groups developed clinical signs, that consisted of anorexia, lethargy, ruffled feathers and dyspnoea, and parasitism in tissues. Two of the five budgerigars died on the 25th and 29th days after infection (DAI). The other three budgerigars were posted on the 30th DAI. In all the five infected birds were observed meronts in the capillaries of the lungs and cysts in muscles, mainly in the tongue and legs.

Chewing lice of the species Afrimenopon waar (Eichler) were collected from captive budgerigar Melopsittacus undulatus (Shaw) in Pakistan. This is the first record of amblyceran lice from this host. It is also the first record of the genus Afrimenopon from Pakistani region. The primary host species of Afrimenopon waar is the rosy-faced lovebird Agapornis roseicollis (Vieillot). The finding of A. waar on budgerigars is, most likely, a result of a contamination in captivity. Morphological variation and origin of these lice are discussed.

Background: The aim of this study was to determine a parasitic species composition, prevalence and intensity of infection in selected parrots., Material and Methods: The studies were carried out on faecal samples of budgerigars Melopsittacus undulatus (n = 36), cockatiels Nymphicus hollandicus (n = 21), grey parrots Psittacus erithacus (n = 18), eastern rosella Platycercus eximius (n = 10) and senegal parrots Poicephalus senegalus (n = 10) using the Willis-Schlaff and McMaster's methods., Results: Protozoans (Isosporidae and Eimeriidae) and nematodes (Ascarididae, Capillaridae and Heterakidae) were detected in the tested samples. Coccidian oocysts were detected in all examined parrots. Isospora and Eimeria oocysts were found in 52.9% Melopsittacus undulatus, 60% Poicephalus senegalus and 66.7% Psittacus erithacus. Mean number of oocysts per gram of feces (OPG) was high: from about 270 to 1500 depending on both parasite and host species. Three species of parrots were infected with the nematodes (Nymphicus hollandicus and Poicephalus senegalus were free from this infection), but only Ascaridia platycerci was present in these hosts, with the highest prevalence (20%) and highest mean number of eggs per gram of feces (EPG = 1242) in Platycercus eximinus. Heterakis gallinarum was observed only in Psittacus erithacus; 16.6% individuals were infected, and EPG was 212. The highest intensity of infection with nematodes of Ascarididae and Capillaridae was in Platycercus eximius. EPG in this species of parrots was 1242 and 2480, respectively. The obtained results show that introduction of parasitological prophylaxis programs is necessary, especially in the larger birds' farmings and zoological shops.