Opportunistic sampling of wild native and invasive birds reveals a rich diversity of adenoviruses in Australia.

Little is known about the diversity of adenoviruses in wild birds and how they have evolved and are maintained in complex ecosystems. In this study, 409 samples were collected from woodland birds caught for banding (droppings), birds submitted to a wildlife hospital (droppings and tissues), silver gulls (droppings or tissues), and feral pigeons (Columbia livia; oral, cloacal swabs, or tissues) from the Greater Sydney area in NSW, Australia. Additional samples were from native pigeons and doves (swabs) presented to the Healesville Sanctuary, VIC, Australia. Samples were screened for adenovirus DNA using degenerate primers and polymerase chain reaction. Adenovirus sequences were detected in eighty-three samples representing thirty-five novel amino acid sequences. Fourteen novel sequences were atadenoviruses, seven were aviadenoviruses, twelve were siadenoviruses, and one was a mastadenovirus. Sequences from passerine birds were predominately found to form a single lineage within the atadenoviruses, a second lineage in the siadenoviruses, and a third smaller aviadenovirus lineage. These viruses appeared to have co-evolved with a diverse group of woodland birds that share similar habitat. Evidence for host/virus co-evolution in some viruses and a wide host range in others was observed. A high prevalence of adenovirus infection was found in rainbow lorikeets (Trichoglossus haematodus), galahs (Eolophus roseicapilla), and sulphur-crested cockatoos (Cacatua galerita). Sequences were either identical to or mapped to already established lineages in the Aviadenovirus, Siadenovirus, and Atadenovirus genera, suggesting a possible origin of the psittacine adenoviruses in ancestral Australian psittacine birds. The sequences of passerine and psittacine origin provided insight into diversity and structure of the Atadenovirus genus and demonstrated for the first-time viruses of passerine origin in the Aviadenovirus genus. Four unrelated adenovirus sequences were found in silver gull samples (Chroicocephalus novaehollandiae), including one of pigeon origin, suggesting environmental virus exposure. Three pigeon adenovirus types were detected in feral pigeons and infection prevalence was high. Evidence for host switching between invasive species and native species and native species and invasive species was documented. A variant of a murine adenovirus was detected in kidney tissue from two bird species suggesting mouse to bird transmission.

A survey of a mixed species aviary provides new insights into the pathogenicity, diversity, evolution, host range, and distribution of psittacine and passerine adenoviruses.

A Bourke's parrot (Neopsephotus bourkii) originating from an aviary in Australia, containing two species of parrots, five species of finch and a species of dove, was presented for necropsy. The Bourke's parrot died from gastritis caused by Macrorhabdus ornithogaster, but also had an interstitial nephritis and ureteritis with adenovirus-like inclusion bodies within collecting duct epithelial cells. The adenovirus causing the lesions was shown to be Psittacine adenovirus-2 (PsAdV-2) using a PCR assay specific for adenoviruses and sequencing of amplicons. A survey of droppings from other birds in the aviary using the same PCR assay with amplicon sequencing found a high prevalence of infection of PsAdV-2 in Bourke's and scarlet-chested parrots (Neophema splendida). PsAdV-2 was also present in droppings from a Namaqua dove (Oena capensis). Gouldian finches (Erythrura gouldiae), red-billed firefinches (Lagonosticta senegala), and red-throated parrot finches (Erythrura psittacea) were shedding Gouldian finch adenovirus-1 (GFAdV-1). Two novel adenoviruses, an atadenovirus and a siadenovirus, were detected in the droppings from long-tailed finches (Poephila acuticauda). Kidney tissue from three of four scarlet-chested parrots submitted for necropsy from a second aviary were also positive for PsAdv-2. These findings and previously reported findings of widespread PsAdv-2 infection in captive orange-bellied parrots (Neophemia chrysogaster) raise the possibility that PsAdV-2 is enzootic in Australian aviculture. This represents the first report of GFAdV-1 in Australia and first identification of infection in finch species other than the Gouldian finch. Identification of two novel adenoviruses in long-tailed finches suggests that other novel adenoviruses are circulating in other finch species. RESEARCH HIGHLIGHTS Psittacine adenovirus-2 was present in high prevalence in two Australian aviaries. Gouldian finch adenovirus-1 (GFAdV-1) was detected in Australia for the first time. The host range of GFAdV-1 host range was expanded to other finch species. Novel atadenovirus and siadenovirus were detected in Estrildid finches.

Hematologic and biochemical reference intervals of free-living Red-Tailed Amazon parrot (Amazona brasiliensis) nestlings on Rasa Island, Paraná, Brazil.

BACKGROUND: The Red-Tailed Amazon parrot (Amazona brasiliensis) is an endangered species of the Psittaciformes. There is little information about hematologic and biochemical variables of this species. OBJECTIVES: The purpose of this study was to determine hematologic and biochemical RIs for free-living A brasiliensis nestlings on Rasa Island, Paraná, Brazil, and to compare the results between sexes. METHODS: Thirty-seven parrots were taken from their nests and physically restrained for clinical examination and blood collection. The sex was diagnosed by PCR using the blood samples collected. Reference intervals were determined as recommended by the ASVCP guidelines in healthy nestlings. The difference between groups was analyzed using the Mann-Whitney test or Student's t-test. RESULTS: Sexing revealed 12 females and 25 males. The RIs for the measured variables were as follows: RBC 1.1-2.6 × 106 /µL, PCV 29.1-50.3%, HGB 7.2-12.9 g/dL, MCV 152-293 fL, MCHC 22.2-28.4 g/dL, WBC 4.9-28.5 × 103 /µL, 1.2-16 × 103 /µL, lymphocytes 2.4-18.7 × 103 /µL, monocytes 0.0-1.0 × 103 /µL, eosinophils 0.0-0.9 × 103 /µL, 0.0-1.3 × 103 /µL, heterophil:lymphocyte ratio 0.0-2.2, plasma total solids 2.1-3.7 g/dL, uric acid 0.5-2.0 mg/dL, glucose 184.9-284.3 mg/dL, AST 100.3-226.6 U/L, LDH 178.1-927.7 U/L, CK 149.8-1144.0 U/L, cholesterol 137.5-256.9 mg/dL, total protein 1.8-3.0 g/dL, calcium 7.0-8.6 mg/dL, and phosphorus 2.9-6.1 mg/dL. Increased concentrations of cholesterol (P < .05) were observed in females. DISCUSSION: This is the first study to establish hematologic and biochemical RIs for free-living A brasiliensis nestlings on Rasa Island. Hematologic and biochemical variables are important tools for evaluating the health status of free-living birds, and also support conservation planning for endangered species.

Reference intervals for biochemical analytes of captive Black-Fronted Piping-Guan (Aburria jacutinga).

BACKGROUND: Black-Fronted Piping-Guan (Aburria jacutinga) is considered one of the most threatened bird species on the American continent. Ex situ conservation efforts have been developed in Brazil, and monitoring the health status of these populations is essential to ensure reproductive success in captivity. Reference intervals (RI) for biochemistry analytes from a larger population of Black-Fronted Piping-Guan are unavailable. OBJECTIVES: This study was aimed at establishing RI for biochemical analytes of captive Black-Fronted Piping-Guan for future improved health assessments in these animals. METHODS: Blood samples were collected from 32 adult Black-Fronted Piping-Guans for serum and plasma separation. Liver and kidney function markers, and concentration of protein and lipids were measured. Reference intervals were determined using an Excel program with Reference Value Adviser (version 2.0). RESULTS: The RI of the analytes were: AST 20.7-188.0 U/L; CK 713.7-4741.4 U/L; LDH 360.7-1173.7 U/L; γ Glutamyl Transferase 1.1-5.4 U/L; total plasma protein 3.5-6.2 g/dL; total serum protein 1.7-4.7 g/dL; uric acid 0.9-19.2 mg/dL; urea 7.0-25.3 mg/dL; cholesterol 71.8-232.2 mg/dL; triglycerides 25.6-183.4 mg/dL. CONCLUSIONS: The RI are similar to the ones published for other avian species. Only CK and uric acid values were in discordance with the usually reported avian ranges. This could be due to different methods of capture and physical restraint. Alternatively, some differences could be species-specific. In general, physical restraint should be limited to a minimum and without stress to prevent capture myopathy and death.

Hematologic and Total Plasma Protein Values in Free-Living Red-tailed Amazon Parrot Nestlings (Amazona brasiliensis) in Paraná State, Brazil.

The red-tailed Amazon parrot (Amazona brasiliensis) is an endangered psittacid species that is endemic in the south and southeast Brazilian Atlantic coastal region. Hematologic evaluation is important to monitor the health of these birds, and information about laboratory values for this species is scarce. Hematologic and total plasma protein profiles were determined for 33 free-living nestling parrots in Paraná state, Brazil. Parrots were temporarily removed from the nest and manually restrained to record body weight and collect blood samples. Mean body weight was <400 g in 13 birds (group 1) and >400 g in 20 birds (group 2). Significantly higher levels of mean corpuscular hemoglobin concentrations, white blood cell counts, monocytes, and basophils were observed in younger birds (group 1). A stress leukogram (high white blood cell and heterophil count) was found in all nestlings, suggesting stress induced by capture and restraint. Parameters obtained in this study will be essential to assess the physiologic and pathologic condition of wild parrots, to evaluate the effects of environmental changes on their health, and to contribute to conservation efforts of this endangered species.