Molecular identification of encephalitozoon hellem in an ostrich

Microsporidia are obligate, intracellular, eukaryotic parasites found in a wide variety of vertebrate and invertebrate hosts. Scientific literature contains a small number of reports of these parasites in psittacine hosts, and recently microsporidiosis was reported in the first nonpsittacine host, an ostrich. DNA was extracted from formalin-fixed, paraffin-embedded ostrich tissues, and a portion of the small subunit ribosomal RNA gene was sequenced to identify the microsporidian species. The organisms were identified as Encephalitozoon hellem, a parasite species that was first described in immunocompromised humans and recently reported in three psittacine species.     

Wound management in nonpsittacine birds.

Although nonpsittacine avian species comprise many different groups of birds, basic medical and surgical principles common to wound management in many vertebrate species are still applicable. This article will delve into examination and wound assessment along with therapeutic stabilization of wounded nonpsittacine birds. An overview of common case presentations that lead to a necessity for wound care are included, and may focus on one particular avian group, but the information can be used on a variety of avian species.     

Avian polyomavirus infection and disease in a green aracaris (Pteroglossus viridis).

Avian polyomavirus (APV) is one of the most significant pathogens of domestically raised psittacine birds (parrots). One or more APVs are suspected to infect nonpsittacine cage birds, but the relationship of these viruses to the APV infecting parrots remains unclear. In this report, for the first time, we fully document an APV infection in a nonpsittacine cage bird, a green aracaris (Pteroglossus viridis). Grossly, this bird evidenced generalized hemorrhage. Histologically, there was severe hepatic necrosis, splenic necrosis, and the presence of lightly basophilic to clear pannuclear inclusion bodies and karyomegaly in splenocytes and renal mesangeal cells, all characteristic lesions of APV infection in parrots. APV DNA was amplified directly from the liver by polymerase chain reaction and sequenced. The virus differed from the original APV sequence by only 24 base pairs (0.48% of the genome), demonstrating that it is a variant of the APV. A serologic survey of the remaining birds in the aviary demonstrated anti-APV antibody in two cockatoos, two cockatiels, a laughing kookaburra, a Lady Ross turaco, and five zebra finches. The remaining green aracaris was seronegative. The sequence and serologic data suggest that the APV that infected the green aracaris originated in a parrot and was capable of infecting birds from at least four orders.     

A universal polymerase chain reaction for the detection of psittacine beak and feather disease virus.

A universal PCR assay was designed that consistently detected psittacine beak and feather disease virus (BFDV) in psittacine birds affected with psittacine beak and feather disease (PBFD) from different geographic regions across Australia. Primers within open reading frame 1 (ORF1) of the BFDV genome consistently amplified a 717 bp product from blood and/or feathers of 32 birds with PBFD lesions. The PCR did not amplify a product from the feathers or blood from 7 clinically normal psittacine birds. Primers based on regions outside of ORF1 did not consistently produce a PCR product, suggesting there was some genomic variation outside ORF1. The amplified ORF1 PCR products of 10 BFDV isolates, from different psittacine species and from various regions around Australia, were cloned and comparative DNA sequence analysis demonstrated 88-99% of the ORF1 fragments. The derived amino acid sequences of the amplified ORF1 fragments demonstrated similar identity between all 10 isolates. Within ORF1, there was complete conservation of the putative nucleotide binding site and marked conservation of 2 other motifs previously identified as essential components of the replication-associated proteins of other circoviruses and geminiviruses.     

Investigation of parrot papillomavirus in cloacal and oral papillomas of psittacine birds

Cloacal and oral papillomas from 27 psittacine birds of various species were examined for the presence of parrot papillomavirus by DNA in situ hybridization, DNA in situ polymerase chain reaction, and nested polymerase chain reaction. Parrot papillomavirus was detected in one oral papilloma from an African grey parrot by all three techniques. In addition, rare basophilic intranuclear inclusions were observed by light microscopy in tissue sections of the oral papilloma from this parrot. The remaining lesions were negative for parrot papillomavirus DNA. This study suggests that parrot papillomavirus may be involved in the development of papillomas in African grey parrots, but apparently is not responsible for development of similar lesions in unrelated species of psittacine birds.     

The sensitivities of various erythrocytes in a haemagglutination assay for the detection of psittacine beak and feather disease virus

The erythrocytes of various species were tested in psittacine beak and feather disease (PBFD) virus haemagglutination (HA) and haemagglutination inhibition assays to determine which are suitable for use in these assays. HA activity was observed for erythrocytes of the salmon-crested cockatoo, the sulphur-crested cockatoo, the umbrella cockatoo, the goffin's cockatoo and the cockatiel, with differences amongst individuals within species, but not for erythrocytes of humans, the pig, the guinea pig, the chicken, the goose, the rose-ringed parakeet or the budgerigar. Anti-PBFD virus rabbit sera inhibited the virus-induced agglutination of erythrocytes, confirming the specificity of HA activity. This suggests that selection of suitable psittacine species as well as suitable individuals within a species is necessary when obtaining erythrocytes for the PBFD virus HA assay.     

Protein electrophoresis of psittacine plasma

BACKGROUND: Although protein electrophoresis (EPH) has been widely applied in human and veterinary medicine, it has only recently been implemented in the analysis of avian samples. OBJECTIVE: The purpose of this study was to examine the application of protein EPH to the analysis of psittacine plasma samples. Our goals were to describe protein fraction mobility, establish reference intervals for some common species, determine the coefficient of variation (CV) of the chosen method, and examine the effects of sample handling and sample condition. METHODS: Heparinized plasma samples from several common psittacine species (minimum sample size 50 each) were examined using the Beckman Paragon system and SPEP-II gels. Total protein was measured by refractometry. Reference intervals (95%) were calculated by the rank methods. RESULTS: Fraction migration patterns were found to vary among common psittacine species. Day-to-day CV for the EPH fractions ranged from 2.2% to 10.5%; within-run CV ranged from 4.8% to 10.8%; and total CV ranged from 3.2% to 14.8%. The highest CV was noted for the poorly defined alpha-globulin fraction. Prolonged refrigeration, repeated freeze-thawing, hemolysis, and lipemia altered the results. CONCLUSIONS: Protein fractions from psittacine species were variable in terms of migration pattern and protein concentration, which necessitates the use of species-specific reference intervals. Avian protein electrophoretic patterns and values should be interpreted based on knowledge of the CV associated with the technique as well as on the effects of sample handling and condition.     

Psittacine beak and feather disease virus in budgerigars and ring-neck parakeets in South Africa

Psittacine beak and feather disease (PBFD) is a common disease of the psittacine species and is caused by the psittacine beak and feather disease virus (PBFDV). In this study the occurrence of the disease in ring-neck parakeets and budgerigars in South Africa suffering from feathering problems, using polymerase chain reaction as a diagnostic test was investigated. The genetic variation between viral isolates was also studied. Results indicate that PBFDV can be attributed to being the cause of feathering problems in some of the ring-neck parakeets and budgerigars in South Africa. Genetic variation of isolates occurs between species and individuals. A cheap and easy to use method of blood sample collection on filter paper for diagnostic purposes was also evaluated. It proved to be less stressful to the birds and did not inhibit further processes.     

Species-related differences in the incidence of gram-negative bacteria isolated from the cloaca of clinically normal psittacine birds

Cloacal swabs from 506 clinically normal psittacine birds of 22 species were aerobically cultured for bacteria and yeasts. In 45 (9%) samples, no microbial organisms were recovered. Gram-positive bacteria were recovered from 474 (91%) samples. The incidences of gram-negative bacteria and yeasts were: Escherichia coli 157 (31%), Enterobacter sp. 21 (4%), Klebsiella sp. 3 (0.6%), Pseudomonas sp. 4 (0.8%), and yeasts 26 (5%). Differences were noted in the recovery rate of E. coli among the various species of birds cultured. Escherichia coli was recovered from 101 of 168 cockatoos (60%) of the genus Cacatua but from only 18% of 338 non-Cacatua species. As all birds were housed in the same facility under similar conditions, this difference in the incidence rate of E. coli cannot be explained on the basis of differences in husbandry or diet alone.     

Psittacine beak and feather disease syndrome in a cockatoo

Psittacine beak and feather disease syndrome was diagnosed in an adult sulfur-crested cockatoo with a history of chronic, progressive feather loss and beak necrosis. A definitive diagnosis was made on the basis of clinical signs and the observation of intracytoplasmic and intranuclear inclusions in involved feather follicular epithelium. Psittacine beak and feather disease syndrome develops in a variety of psittacine species and usually has a progressive and irreversible clinical course. Symmetric feather loss with replacement by severely dystrophic plumage is the salient clinical finding. Beak elongation and breakage also may be found. Treatment of diseased birds remains palliative and consists of a controlled environment, balanced nutrition, antibiotics, and autogenous vaccines. Avian practitioners should include psittacine beak and feather disease syndrome as a potential cause for pathologic feather loss in caged birds.     

Newcastle disease.

Since 1926, there have been three epizootics of ND. The latter two have been directly linked with psittacine species and Racing Pigeons. The modern poultry industry is extremely vulnerable to the effects of NDV, once it gains entry to any facet of the industry. Consequently considerable expense and effort are expended to keep the virus at bay. The main threat continues to come from psittacine species and racing pigeons. The considerable international trade in these birds, together with rapid air transport, can allow virulent NDV to gain entry to a country while exotic birds are incubating the disease. It is hoped that quarantine barriers and requirements will prevent the virus from entering a country, but smuggling continues and constitutes the biggest risk. Domestic avian pets are also vulnerable to the virus. It is hoped that new in vitro testing procedures, such as monoclonal antibody and oligonucleotide fingerprinting techniques, may be used to identify rapidly and characterize emergent virulent strains, so that appropriate measures may be taken to prevent infection of commercial poultry and domestic pets.     

Papillomavirus infection in greenfinches (Carduelis chloris).

The present report describes transmissible papillomatous digital lesions observed in two greenfinches (Carduelis chloris) living in a private aviary. The disease appeared in the male bird and successively in the female but did not affect other passerine and psittacine species living with the sick birds. Negative contrast electron microscopy revealed the presence of 52.6 nm virus particles similar to papillomavirus. Immunoelectronmicroscopy confirmed the presence of Papillomavirus genus specific structural antigens in the virus observed.     

First detection and molecular characterization of avian polyomavirus in young parrots in Pakistan

Veterinary Research Communications - Avian polyomavirus (APV) infection, also called as budgerigar fledgling disease (BFD) causes various health problems in many psittacine species which may cause...     

Serological evaluation of some psittaciformes for budgerigar fledgling disease virus

Breeding psittaciform birds (psittacines) from three geographically separated aviaries experiencing fledgling mortality were monitored during 1983 and 1984 for specific serum antibody to budgerigar fledgling disease virus (BFDV) using a fluorescent-antibody virus-neutralization test. Neither the time nor the extent of exposure to the virus was known. Serological titers were positive in 45% of birds sampled from Aviary 1, 25% from Aviary 2, and 11% from Aviary 3. Several species of psittacine birds within each aviary were serologically positive for BFDV. The results indicated that a papovavirus similar to BFDV appears to infect a wide range of captive adult psittacine birds. Macaws (Ara sp. and Anodorhynchus sp.) were evaluated for distribution of infection. Each species within these two genera showed positive serological titers to BFDV. Three groups of birds showed a decrease in serum antibody titer to BFDV at 1 and 2.5 months after the first sampling. Positive titers decreased from 66 to 20% for one group and from 60 to 50% for a second group in 1 month, and they decreased from 42 to 17% for a third group in 2.5 months.     

Detection and sequence analysis of avian polyomavirus and psittacine beak and feather disease virus from psittacine birds in Taiwan

Avian polyomavirus (APV) and psittacine beak and feather disease virus (PBFDV) are the most common viral diseases of psittacine birds. In Taiwan, however, the existence of these viruses in psittacine birds has not been established. Polymerase chain reaction (PCR) methodology was therefore employed to ascertain whether APV and PBFDV genomes were present in isolates from psittacine birds of Taiwan. A total of 165 psittacine birds belonging to 22 genera were examined between 2002 and 2005. Findings revealed an APV-positive rate of 15.2%, a PBFDV-positive rate of 41.2%, and an APV/PBFDV dual infection rate of 10.3%. After cloning and sequencing, sequences of the PCR products were compared with sequences obtained from GenBank. For APV, the nucleotide identity among VP1 and t/T antigen coding regions ranged from 97.5% to 100% and 97.6% to 100%, respectively. For PBFDV, the nucleotide identity of ORF V1 and ORF C1 sequences ranged from 92.2% to 100% and 83.3% to 100%, respectively. The derived amino acid sequence alignment for PBFDV ORF V1 fragments revealed the conservation of two replication motifs and of the nucleotide binding site motif. In PBFDV, six of 42 deduced positions in the ORF C1 amino acid sequence were considered hypervariable. The established phylogenetic trees based on the four genome fragments examined in this study did not allow the assignment of particular APV or PBFDV nucleotide sequences to distinct avian species.     

Anseriform and galliform therapeutics.

This article provides the reader with an overview of the therapeutic options for members of the orders Anseriformes and Galliformes. These orders make up a large variety of nonpsittacine birds that are seen in veterinary practice or in zoos and private collections. Standard therapeutics are discussed as well as recently developed protocols. Order-specific idiosyncrasies are addressed. A formulary for each order is provided by drug category.     

A survey to detect subclinical polyomavirus infections of captive psittacine birds in Germany

Infections of avian polyomavirus (APV) are known to cause fatal disease in a wide range of psittacine and non-psittacine birds. Here, we present a survey to investigate the existence of subpopulation of persistent or subclinically infected parrots inside the population of captive psittacine birds in Germany. DNA was isolated from feathers of 85 symptom-free birds from 20 different genera (all psittaciformes) taken from 30 different breeders from all over Germany. The presence of APV was analysed by performing polymerase chain reaction assays (PCR). APV was detected in none of the samples, indicating that the existence of a subpopulation of captive psittacine birds having a persistent APV infection in Germany seems to be relatively low.     

Comparative efficiency and accuracy of surgical and cytogenetic sexing in psittacines

Otoscopic surgical sexing and chromosome analysis through lymphocyte culture were undertaken in 22 psittacine birds of eight species for the purpose of establishing their sex. Comparison of the techniques involved considering success rate, quality of determination, cost, efficiency, and risk. Surgical endoscopy appears to be preferable to chromosome analysis in all categories except risk.     

A novel DNA virus associated with feather inclusions in psittacine beak and feather disease

The nature of feather inclusions was characterized in 32 psittacine birds (30 cockatoos, one peach-faced lovebird (Agapornis roseicollis), and one red-lored Amazon parrot (Amazona autumnalis autumnalis] with naturally-acquired psittacine beak and feather disease. Intranuclear inclusions within feather epithelial cells and intracytoplasmic inclusions within macrophages in the feather epithelium and pulp cavity contained psittacine beak and feather disease viral antigen when stained by the avidin-biotin complex immunoperoxidase technique. Ultrastructurally, inclusions were observed primarily within macrophages and to a lesser extent within epithelial cell nuclei. Macrophage inclusions appeared as paracrystalline arrays of viral particles. Intranuclear inclusions were less well defined, although scattered viral particles were present. Intracytoplasmic and intranuclear particles in ultrastructural preparations were identified by colloidal gold labeling as psittacine beak and feather disease virus. Feather epithelium was more frequently and severely involved in the disease process than was adjacent follicular epithelium. Plucked feathers with an intact epidermal collar and feather epithelium were preferred to follicular biopsies for histopathologic examination.