RESUMO

Parrot bornavirus (PaBV) is an RNA virus that causes Proventricular Dilatation Disease (PDD), neurological disorders, and death in Psittaciformes. Its diversity in South America is poorly known. We examined a Cacatua galerita presenting neuropathies, PDD, and oculopathies as the main signs. We detected PaBV through reverse transcription polymerase chain reaction (RT-PCR) and partial sequencing of the nucleoprotein (N) and matrix (M) genes. Maximum likelihood and Bayesian phylogenetic inferences classified it as PaBV-2. The nucleotide identity of the sequenced strain ranged from 88.3% to 90.3% against genotype PaBV-2 and from 80.2% to 84.4% against other genotypes. Selective pressure analysis detected signs of episodic diversifying selection in both the N and M genes. No recombination events were detected. Phylodynamic analysis estimated the time to the most recent common ancestor (TMRCA) as the year 1758 for genotype PaBV-2 and the year 1049 for the Orthobornavirus alphapsittaciforme species. Substitution rates were estimated at 2.73 × 10-4 and 4.08 × 10-4 substitutions per year per site for N and M, respectively. The analysis of population dynamics showed a progressive decline in the effective population size during the last century. Timescale phylogeographic analysis revealed a potential South American ancestor as the origin of genotypes 1, 2, and 8. These results contribute to our knowledge of the evolutionary origin, diversity, and dynamics of PaBVs in South America and the world. Additionally, it highlights the importance of further studies in captive Psittaciformes and the potential impact on endangered wild birds.

RESUMO

Proventricular dilatation disease is a lethal disease of psittacine birds. In this study, we characterized the local cellular immune response in the brain, proventriculus, and small intestine of 27 cockatiels (Nymphicus hollandicus) experimentally infected with parrot bornavirus 2 (PaBV-2). Perivascular cuffs in the brain were composed of CD3+ T-lymphocytes and Iba1+ macrophages/microglia in most cockatiels (n = 26). In the ganglia of the proventriculus, CD3+ T-lymphocytes (n = 17) and Iba1+ macrophages (n = 13) prevailed. The ganglia of the small intestine had a more homogeneous distribution of these leukocytes, including PAX5+ B-lymphocytes (n = 9), CD3+ T-lymphocytes (n = 8), and Iba1+ macrophages (n = 8). Our results indicate that perivascular cuffs in the brain and the inflammatory infiltrate in the proventriculus of PaBV-2-infected cockatiels is predominately composed of T-lymphocytes, while the inflammatory infiltrates in the ganglia of the small intestine are characterized by a mixed infiltrate composed of T-lymphocytes, B-lymphocytes, and macrophages.

Assuntos

RESUMO

Lymphoplasmacytic inflammation associated with bornavirus N protein occurs in the epicardial ganglia, myocardium and endocardium of birds diagnosed with proventricular dilatation disease (PDD). These pathological findings suggest that sudden death in psittacine birds might stem from cardiac compromise due to parrot bornavirus (PaBV) infection. Therefore, we investigated cardiac lesions in cases of PDD, searching databases from 1988 to 2019, and reviewed three experimental studies of PaBV infection. Fifty cases of PDD in birds infected naturally with PaBV and 27 cases of PDD in birds infected experimentally with PaBV (all having descriptions of inflammatory cardiac lesions) were reviewed. For each case, five regions of the heart were evaluated by light microscopy and immunohistochemistry (IHC). These regions were the epicardial ganglia/nerves, the endocardium, the myocardium, the Purkinje fibres and the great vessels. Sudden death was documented in 17/50 naturally infected cases, while 23/50 had digestive signs, and only 12/50 had neurological signs. Grossly, only five naturally-infected and five experimentally-infected cases had cardiomegaly or hydropericardium. Epicardial ganglioneuritis was the most consistent microscopical finding in natural (46/50) and experimental cases (26/27), followed by myocarditis (34/50) for naturally-infected and endocarditis for experimentally-infected birds (6/27). PaBV-2 antigen was detected most frequently by IHC in the epicardial ganglia (54/77) compared with the other tissues. This retrospective study demonstrates the presence of PaBV protein and inflammation in the heart of birds infected with PaBV and suggests a link between PaBV and cardiac disease and sudden death in psittacine birds.

Assuntos

RESUMO

Proventricular dilatation disease (PDD) is a lethal and important disease of captive psittacine birds, and affects a wide range of species, including endangered ones, and lacks an effective treatment. This report describes PDD in three blue-and-gold macaws (Ara ararauna) in southern Brazil. All three macaws originated from the same aviary and presented similar clinical signs including anorexia, apathy, emaciation and prostration. At necropsy, one of the macaws presented an enlarged proventriculus. Histologically, lymphoplasmacytic infiltrates was observed in the ganglia and nerves of the esophagus, crop, proventriculus, ventriculus, heart, adrenal glands, and adrenal medulla of all three cases. Two macaws had meningoencephalomyelitis and one had myocarditis. Immunohistochemistry identified PaBV antigen in the brain, proventricular, ventricular ganglia, and epicardial ganglia, and cardiomyocytes of all three macaws.(AU)

A doença da dilatação proventricular (PDD) e uma importante e fatal doença de psitacídeos de cativeiro, que afeta uma grande variedade de espécies e não tem um tratamento efetivo até o momento. Este relato descreve PDD em três araras canindé (Ara ararauna) no sul do Brasil. Todas as três araras eram provenientes do mesmo criatório e apresentaram sinais clínicos semelhantes incluindo anorexia, apatia, emaciação e prostração. Na necropsia, uma das araras apresentou proventrículo dilatado. No exame histopatológico, infiltrados linfoplasmacitários foram observados em gânglios e nervos do esôfago, inglúvio, proventrículo, moela, coração, glândulas adrenais e rins de todos os casos. Adicionalmente, meningoencefalomielite foi observada em duas araras e miocardite em uma. A imuno-histoquímica identificou antígenos de PaBV no encéfalo, coração, proventrículo e moela de todos os casos.(AU)

Assuntos

RESUMO

Proventricular dilatation disease (PDD) is a lethal and important disease of captive psittacine birds, and affects a wide range of species, including endangered ones, and lacks an effective treatment. This report describes PDD in three blue-and-gold macaws (Ara ararauna) in southern Brazil. All three macaws originated from the same aviary and presented similar clinical signs including anorexia, apathy, emaciation and prostration. At necropsy, one of the macaws presented an enlarged proventriculus. Histologically, lymphoplasmacytic infiltrates was observed in the ganglia and nerves of the esophagus, crop, proventriculus, ventriculus, heart, adrenal glands, and adrenal medulla of all three cases. Two macaws had meningoencephalomyelitis and one had myocarditis. Immunohistochemistry identified PaBV antigen in the brain, proventricular, ventricular ganglia, and epicardial ganglia, and cardiomyocytes of all three macaws.(AU)

A doença da dilatação proventricular (PDD) e uma importante e fatal doença de psitacídeos de cativeiro, que afeta uma grande variedade de espécies e não tem um tratamento efetivo até o momento. Este relato descreve PDD em três araras canindé (Ara ararauna) no sul do Brasil. Todas as três araras eram provenientes do mesmo criatório e apresentaram sinais clínicos semelhantes incluindo anorexia, apatia, emaciação e prostração. Na necropsia, uma das araras apresentou proventrículo dilatado. No exame histopatológico, infiltrados linfoplasmacitários foram observados em gânglios e nervos do esôfago, inglúvio, proventrículo, moela, coração, glândulas adrenais e rins de todos os casos. Adicionalmente, meningoencefalomielite foi observada em duas araras e miocardite em uma. A imuno-histoquímica identificou antígenos de PaBV no encéfalo, coração, proventrículo e moela de todos os casos.(AU)

Assuntos

RESUMO

This report describes a case of proventricular rupture associated with Psittaciforme 1 Bornavirus in a 10-year old Major Mitchell Cockatoo (Lophochroa leadbeateri) who presented with a 2-day history of weakness and weight loss. On necropsy, a fibrinonecrotizing coelomitis and an enlarged proventriculus with a 0.5 cm in diameter transmural perforation characterized the main findings. Histology confirmed the locally extensive, transmural necrotizing proventriculitis with coelomitis. Additionally, lymphoplasmacytic ganglioneuritis in the proventriculus, heart, small intestine, and adrenal gland, as well as lymphoplasmacytic encephalitis, hallmarks of proventricular dilatation disease. Psittaciform 1 bornavirus RNA was confirmed in the brain, proventriculus and ventriculus by RT-PCR. Avian Bornavirus antigen was identified by immunohistochemistry in the brain and heart.(AU)

Assuntos

RESUMO

This report describes a case of proventricular rupture associated with Psittaciforme 1 Bornavirus in a 10-year old Major Mitchell Cockatoo (Lophochroa leadbeateri) who presented with a 2-day history of weakness and weight loss. On necropsy, a fibrinonecrotizing coelomitis and an enlarged proventriculus with a 0.5 cm in diameter transmural perforation characterized the main findings. Histology confirmed the locally extensive, transmural necrotizing proventriculitis with coelomitis. Additionally, lymphoplasmacytic ganglioneuritis in the proventriculus, heart, small intestine, and adrenal gland, as well as lymphoplasmacytic encephalitis, hallmarks of proventricular dilatation disease. Psittaciform 1 bornavirus RNA was confirmed in the brain, proventriculus and ventriculus by RT-PCR. Avian Bornavirus antigen was identified by immunohistochemistry in the brain and heart.

Assuntos