Australian Parakeets Research Articles

A pioneering study on cytotoxicity in Australian parakeets (Melopsittacus undulates) exposed to tannery effluent

Waste effluent from the tannery industry is a major source of environmental pollution. Considering that the bird intake of water contaminated with tannery effluent constitutes a potential genotoxic source, especially for birds inhabiting areas closest to tanning industries, the aim of this study is to assess the possible mutagenic effects that the intake may have on Melopsittacus undulatus (Australian parakeet). In order to do so, adult male and female M. undulatus were distributed in two experimental groups: control (drinking water) and TE (5%). After 60 days of exposure, the micronucleus test, as well as tests looking for other nuclear abnormalities in the peripheral blood of the birds were performed. The male and female birds exposed to the pollutant have presented the highest total number of nuclear abnormalities, as well as increased individual abnormalities such as nuclei with symmetrical constricted bi-lobed/bi-nucleated erythrocytes, indented nuclei and micro-lobed nuclei (top)/micro-nuclei (bottom). In addition, the exposure to TE has caused a nuclear variant increase rarely reported in the literature concerning poultry erythrocyte nuclei. The birds exposed to the pollutant have presented the highest frequency of displaced nuclei forming different rotation/displacement angles within the cells. Therefore, the current study confirmed the toxicological potential of TE and was pioneer in showing that male and female M. undulatus exposed to pollutant present the highest frequency of erythrocyte nuclear abnormalities, thus corroborating the initial hypothesis herein presented.

Can the same species of Platynosomum (Trematoda: Dicrocoeliidae) infect both mammalian and avian hosts?

The importance of platynosomiasis has increased in feline veterinary practice, but aspects related to the specificity of Platynosomum spp. in definitive hosts requires further study. Although morphological traits suggest that the same species, P. illiciens, may infect both birds and mammals, the synonymies previously proposed have not been widely accepted, likely because host specificity is assumed. In addition, the name P. fastosum has frequently been used for parasites recovered from mammals. In the present study, metacercariae (n=100/animal) of P. illiciens recovered from lizards (Hemidactylus mabouia) in Brazil were fed to Australian parakeets (Melopsittacus undulatus) and mice. Two parasites were recovered from the liver of one M. undulatus specimen during a necropsy that was performed 105 days after infection, and all mice were found to be infected with 37±12 (18-48) parasites. The morphology of the P. illiciens obtained from the parakeet was similar to that of parasites obtained from mice and those described previously from naturally infected birds and mammals. Non-specificity of P. illiciens in hosts is discussed briefly, based on the parasitological and morphological results obtained during the avian experimental platynosomiasis and the epidemiology and geographical distribution of this parasite.

High-coverage sequencing and annotated assemblies of the budgerigar genome.

BackgroundParrots belong to a group of behaviorally advanced vertebrates and have an advanced ability of vocal learning relative to other vocal-learning birds. They can imitate human speech, synchronize their body movements to a rhythmic beat, and understand complex concepts of referential meaning to sounds. However, little is known about the genetics of these traits. Elucidating the genetic bases would require whole genome sequencing and a robust assembly of a parrot genome.FindingsWe present a genomic resource for the budgerigar, an Australian Parakeet (Melopsittacus undulatus) -- the most widely studied parrot species in neuroscience and behavior. We present genomic sequence data that includes over 300× raw read coverage from multiple sequencing technologies and chromosome optical maps from a single male animal. The reads and optical maps were used to create three hybrid assemblies representing some of the largest genomic scaffolds to date for a bird; two of which were annotated based on similarities to reference sets of non-redundant human, zebra finch and chicken proteins, and budgerigar transcriptome sequence assemblies. The sequence reads for this project were in part generated and used for both the Assemblathon 2 competition and the first de novo assembly of a giga-scale vertebrate genome utilizing PacBio single-molecule sequencing.ConclusionsAcross several quality metrics, these budgerigar assemblies are comparable to or better than the chicken and zebra finch genome assemblies built from traditional Sanger sequencing reads, and are sufficient to analyze regions that are difficult to sequence and assemble, including those not yet assembled in prior bird genomes, and promoter regions of genes differentially regulated in vocal learning brain regions. This work provides valuable data and material for genome technology development and for investigating the genomics of complex behavioral traits.

Pathologic-anatomic and morphometric examinations on the heart in feral cockatoos

To evaluate the heart of free-living psittacine birds macroscopically and morphologically, and to compare the results to findings published for psittacine birds living in captivity to obtain information on the influence of bird keeping in a human environment on the psittacine heart. In total, 84 wild-living cockatoos were examined, including 50 sulphur-crested cockatoos (Cacatua galerita), 31 galahs (Eolophus roseicapilla) and three long-billed corellas (Cacatua tenuirostris). The birds were euthanized because of a local cockatoo control program in Australia, and were examined pathologically within 8 hours of euthanasia. A macroscopic necropsy was performed, and the heart was assessed morphologically. Furthermore, a histological organ screening was conducted. The birds demonstrated good body condition and excellent muscle condition. Except for some paleness of the heart muscle, none of the animals showed any pathological alteration of the heart or large vessels. The mean heart mass was 8.7 g for the sulphur-crested cockatoos, 5.3 g for the galahs and 8.6 g for the long-billed corellas. Independent of the species examined, a highly significant correlation was found between the heart and body masses (r = 0.91; p < 0.001), which was also confirmed as significant within the sulphur-crested cockatoo (r = 0.59; p < 0.001) and galah groups (r = 0.52; p = 0.003). This correlation can be used to calculate the expected heart mass based on the body mass, using the formula: heart mass (g) = 2.9 + 0.01 x body mass (g). In comparison to reports on Australian parakeets, the relative thickness of the heart muscle wall of the left ventricle found in this study was greater. In comparison to psittacine birds kept in captivity, wild-living cockatoos have good body condition and rarely suffer from macroscopically detectable diseases of the heart or large vessels. The cardiac fitness level is superior in comparison to that found in healthy appearing psittacine birds kept in captivity. The results can serve as a basis for the assessment of the heart in psittacine birds, because in contrast to earlier reports, the heart of healthy psittacine birds not previously exposed to any human influence could be assessed.

Histopathologic, immunohistochemical and ultrastructural features of a granular cell tumour in an Australian parakeet (Melopsittacus undulatus)

An adult male Australian parakeet (Melopsittacus undulatus) presented a firm nodular lesion in the lateral metacarpal region of the right wing. Microscopically, there were neoplastic cells, round and polyhedral in shape, with abundant, slightly eosinophilic granular cytoplasm; they were strongly periodic-acid Schiff-positive and resistant to diastase digestion. Some groups of neoplastic cells were immunopositive for smooth muscle actin and desmin. There was no immunopositivity for S-100 protein, CD68 and cytokeratin. Ultrastructurally, the neoplastic cells were round and polygonal in shape, and they were characterized by abundant cytoplasm with numerous homogeneous osmophilic bodies covered by an electron-dense membrane (lysosomes). The histopathologic, immunohistochemical and ultrastructural features of the neoplastic tissue are consistent with a granular cell tumour, which has been described in different animal species and anatomic locations; however, this seems to be an infrequent neoplasm in Australian parakeets. The immunopositivity of the neoplastic cells for smooth muscle actin and desmin, as well as slight positivity for muscle with Masson's trichrome, suggest that this is a tumour of myogenic origin.

Topografia e morfologia das vísceras do periquito-australiano (Melopsittacus undulatus, Shaw 1805)

The aim of this research was to study the topography and morphology of Australian parakeet (Melopsittacus undulatus) viscera. Ten Australian parakeet were used (5 males and 5 females). The animals were fixed in 10% formaldehyde solution, through perfusion in the musculature and visceral cavity. Macroscopically, the Australian parakeet viscera did not show expressive differences when compared to other domestic birds’ species. Microscopically, the main difference was the presence of mechanoreceptors (Corpuscles of Pacini) in the tongue, found for the first time in this psittaciform species. KEY WORDS: Melopsittacus undulatus, morphology, topography, viscera.

Common disorders of amazons, Australian Parakeets, and African Grey Parrots

Amazons, Australian Parakeets, and African Grey Parrots are more and more becoming popular pets. In order to provide better service to these species, the veterinary practitioner must become familiar with their common medical problems. In this article, we will discuss the common medical disorders seen in these species.

Parrot Evolution and Paleogeographical Events: Mitochondrial DNA Evidence

*Departamento de Biologia, Instituto de Biocieˆncias–Universidade de Sa˜o Paulo, Sa˜o Paulo, Brazil; and †Department ofZoology, University of Leicester, Leicester, EnglandWe sequenced 1,771 bp of three mitochondrial genes (12S rDNA, 16S rDNA, and cytochrome b) of nine NewWorld parrot genera (Amazona aestiva, Anodorhynchus hyacinthinus, Ara ararauna, Aratinga aurea, Cyanopsittaspixii, Deroptyus accipitrinus, Guaruba guarouba, Pionus menstruus, and Pyrrhura picta) and compared them withthe corresponding sequence of Australian parakeet (Melopsittacus undulatus). Phylogenetic analyses (maximumparsimony and maximum likelihood) showed that the Neotropical species we studied constitute two monophyleticgroups: the long-tailed and the short-tailed species. The separation within the long-tailed species could be assignedto the late Oligocene–early Miocene, when paleoenvironmental changes might have influenced this radiation. Thelong-tailed Neotropical and Australasian species diverged during the Cretaceous–Tertiary boundary, when SouthAmerica and Australia were moving away from Antarctica (Gondwanaland fission). We also compared our datawith the cytochrome b sequences of seven different genera of Australasian parrots obtained by other investigators,and these comparisons also support the independent evolution of the Neotropical and Australasian species. Analysesperformed with 567 bp of partial sequences of 12S rDNA and cytochrome b did not support or refute the hypothesisof monophyly of the Neotropical parrots with respect to an African species whose sequences were available.However, this analysis supported the view that the divergence between Neotropical short- and long-tailed taxa wasolder than the Oligocene–Miocene divergence among the long-tailed genera.

Studies on a virus isolated from the brain of a parakeet(Neophema sp)

Haemagglutinating viruses were isolated from Australian parakeets and from aviary birds of the order Passeriformes. In all cases the affected birds showed symptoms of disease of the nervous system. One of the isolates, 449, has the physico-chemical and biological properties of the paramyxoviruses. Comparative serological and animal-experimental investigations suggested that this isolate could be a deviating strain of Newcastle disease virus.

Cardiac zygomycosis in an Australian parakeet.

The histopathological findings in a case of cardiac zygomycosis in an Australian parakeet are reported.

Acarinose dos sacos aéreos de canários (Serinus canarius L.) e periquitos australianos (Melopsittacus undulatus, Shaw 1805) por Cytodites nudus (Vizioli, 1868)

In this paper the authors describes, in a group of canaries, a bronchitis caused by an infestation of the air sacs, by Cytodites nudus (Vizioli, 1868). They further described the observed symptoms, mainly those which are due to the disturbance of the breathing system (intense dyspnea, cough, sneezing, noisy breathing and congestion of the larynx) and those of exciting of the neural system (convulsions with tonic and clonic contractions). The more frequent lesions are: inflammation of the air sacs, with the presence of liquids, mucus and blood coagulum in the cavities. Pericarditis and adherences of the pericardium to the thorax walls. The treatment was based, on fluidifiers and expectorants of secretions, containing either potassium iodide or sodium benzoate. There were often found ectoparasites among the breedings, from which came our cases, for which treatment the Sodium fluoride was utilized. The clinics diagnosis was confirmed by necroscopy performed on the patients or on other birds of the same breedings, with similar symptoms. The authors also describes the incidence of Cytodites nudus in the air sacs of Australian Parakeets (Melopsittacus undulatus —Shaw, 1805).