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Background Beak and feather disease virus (BFDV) is a circovirus that infects captive and wild psittacine birds, and is of conservation concern. The haemagglutination inhibition (HI) assay is used to determine antibody titres against BFDV, and the use of dried blood spots (DBS) on filter paper stored at room temperature has been suggested to be an equally valid technique to the use of frozen serum. However, research on other pathogens has found variable results when investigating the longevity of antibodies stored on DBS at room temperature. Consequently, we aimed to test the temporal stability of antibodies to BFDV in DBS samples stored long-term at room temperature. A further goal was to add to the current knowledge of antibody response to naturally acquired BFDV infection in crimson rosellas (Platycercus elegans). Methods Blood was collected from wild P. elegans in Victoria, Australia, that had been live-trapped (n = 9) or necropsied (n = 11). BFDV virus load data were obtained from blood stored in ethanol by real-time quantitative PCR (qPCR); antibody titres were obtained by HI assay from either DBS or serum samples, which had been collected concurrently. All HI assays were performed commercially by the Veterinary Diagnostic Laboratory (VDL) in Charles Sturt University, Australia, who were blind to BFDV blood status. Results HI titres from DBS stored at room temperature declined significantly over time (~80 weeks). By contrast, frozen serum samples assayed after 80 weeks in storage all had high HI titres, only varying up to one dilution step from the initial HI titres obtained from DBS at 3–6 weeks after sampling. Weak HI titres from DBS samples all came back negative when the test was

Eight lovebirds of both sexes and different age were admitted showing alterations in behaviour and apathy. During the initial examination delamination of the beak was noted in all birds and discrete areas of alopecia in three of eight birds. Based on clinical experience, molecular diagnostic on PBFD, sequencing of obtained amplicons, and histopathological examination were performed. All birds tested positive on the presence of PBFD virus, despite the fact they did not exhibit expected clinical signs for PBFD. Sequencing results showed 100% match with sequences previously isolated from parrots with PBFD exhibiting classical PBFD manifestation. Histopathological examination showed similar findings as in previously described cases of PBFD in parrots. Other studies on psittacine birds correlate clinical manifestations and nucleotide variations with geographic localization. Our results indicate that the clinical manifestation of the disease is more dependent on bird species than on the genetic variation of the virus or the geographical distribution., Osam rozenkolisa oba pola različite starosti su primljeni na pregled zbog uočenih promena u ponašanju i apatije. Tokom inicijalnog pregleda kod svih ptica je uočena delaminacija kljuna, a kod tri jedinke bila su prisutna i diskretna polja alopecije. Na osnovu kliničkog iskustva postavljena je sumnja na oboljenje bolest kljuna i perja te je urađena molekularna dijagnostika na pristutvo virusa bolesti kljuna i perja, sekvencioniranje dobijenih amplifikata i patohistološko ispitivanje. Rezultati ispitivanja su potvrdili prisustvo virusa u uzorcima od svih ispitivanih jedinki, poklapanje nukleotidnih sekvecni od 100% sa uzorcima od drugih ptica sa drugačijom kliničkom slikom, a patohistološke promene su identične onima opisanim kod bolesti kljuna i perja. Studije brojnih autora povezivale su kliničku manifestaciju bolesti sa nukleotidnim varijacijama ili geografskom lokalizacijom. Međutim, opisani rezultati bi mogli da ukazuju da je kliničko ispoljavanje bolesti više zavisno od vrste domaćina nego od genotipa virusa koji bolest izaziva i od teritorije na kojoj se bolest ispoljava.

Eight lovebirds of both sexes and different age were admitted showing alterations in behaviour and apathy. During the initial examination delamination of the beak was noted in all birds and discrete areas of alopecia in three of eight birds. Based on clinical experience, molecular diagnostic on PBFD, sequencing of obtained amplicons, and histopathological examination were performed. All birds tested positive on the presence of PBFD virus, despite the fact they did not exhibit expected clinical signs for PBFD. Sequencing results showed 100% match with sequences previously isolated from parrots with PBFD exhibiting classical PBFD manifestation. Histopathological examination showed similar findings as in previously described cases of PBFD in parrots. Other studies on psittacine birds correlate clinical manifestations and nucleotide variations with geographic localization. Our results indicate that the clinical manifestation of the disease is more dependent on bird species than on the genetic variation of the virus or the geographical distribution., Osam rozenkolisa oba pola različite starosti su primljeni na pregled zbog uočenih promena u ponašanju i apatije. Tokom inicijalnog pregleda kod svih ptica je uočena delaminacija kljuna, a kod tri jedinke bila su prisutna i diskretna polja alopecije. Na osnovu kliničkog iskustva postavljena je sumnja na oboljenje bolest kljuna i perja te je urađena molekularna dijagnostika na pristutvo virusa bolesti kljuna i perja, sekvencioniranje dobijenih amplifikata i patohistološko ispitivanje. Rezultati ispitivanja su potvrdili prisustvo virusa u uzorcima od svih ispitivanih jedinki, poklapanje nukleotidnih sekvecni od 100% sa uzorcima od drugih ptica sa drugačijom kliničkom slikom, a patohistološke promene su identične onima opisanim kod bolesti kljuna i perja. Studije brojnih autora povezivale su kliničku manifestaciju bolesti sa nukleotidnim varijacijama ili geografskom lokalizacijom. Međutim, opisani rezultati bi mogli da ukazuju da je kliničko ispoljavanje bolesti više zavisno od vrste domaćina nego od genotipa virusa koji bolest izaziva i od teritorije na kojoj se bolest ispoljava.

Eight lovebirds of both sexes and different age were admitted showing alterations in behaviour and apathy. During the initial examination delamination of the beak was noted in all birds and discrete areas of alopecia in three of eight birds. Based on clinical experience, molecular diagnostic on PBFD, sequencing of obtained amplicons, and histopathological examination were performed. All birds tested positive on the presence of PBFD virus, despite the fact they did not exhibit expected clinical signs for PBFD. Sequencing results showed 100% match with sequences previously isolated from parrots with PBFD exhibiting classical PBFD manifestation. Histopathological examination showed similar findings as in previously described cases of PBFD in parrots. Other studies on psittacine birds correlate clinical manifestations and nucleotide variations with geographic localization. Our results indicate that the clinical manifestation of the disease is more dependent on bird species than on the genetic variation of the virus or the geographical distribution., Osam rozenkolisa oba pola različite starosti su primljeni na pregled zbog uočenih promena u ponašanju i apatije. Tokom inicijalnog pregleda kod svih ptica je uočena delaminacija kljuna, a kod tri jedinke bila su prisutna i diskretna polja alopecije. Na osnovu kliničkog iskustva postavljena je sumnja na oboljenje bolest kljuna i perja te je urađena molekularna dijagnostika na pristutvo virusa bolesti kljuna i perja, sekvencioniranje dobijenih amplifikata i patohistološko ispitivanje. Rezultati ispitivanja su potvrdili prisustvo virusa u uzorcima od svih ispitivanih jedinki, poklapanje nukleotidnih sekvecni od 100% sa uzorcima od drugih ptica sa drugačijom kliničkom slikom, a patohistološke promene su identične onima opisanim kod bolesti kljuna i perja. Studije brojnih autora povezivale su kliničku manifestaciju bolesti sa nukleotidnim varijacijama ili geografskom lokalizacijom. Međutim, opisani rezultati bi mogli da ukazuju da je kliničko ispoljavanje bolesti više zavisno od vrste domaćina nego od genotipa virusa koji bolest izaziva i od teritorije na kojoj se bolest ispoljava.

The psittacine beak and feather disease (PBFD) is a globally widespread infectious bird disease that mainly affects species within the Order Psittaciformes (parrots and allies). The disease is caused by an avian circovirus (the beak and feather disease virus, BFDV), which is highly infectious and can lead to severe consequences in wild and captive populations during an outbreak. Both legal and illegal trading have spread the BFDV around the world, although little is known about its prevalence in invasive parrot populations. Here, we analyze the BFDV prevalence in sympatric invasive populations of rose-ringed (Psittacula krameri) and monk parakeets (Myiopsitta monachus) in Southern Spain. We PCR-screened 110 blood samples (55 individuals from each species) for BFDV and characterized the genotypes of five positives from each species. About 33% of rose-ringed parakeets and 37% of monk parakeets sampled were positive for BFDV, while neither species showed disease symptoms. The circovirus identified is a novel BFDV genotype common to both species, similar to the BFDV genotypes detected in several parrot species kept in captivity in Saudi Arabia, South Africa and China. Our data evidences the importance of an accurate evaluation of avian diseases in wild populations, since invasive parrots may be bringing BFDV without showing any visually detectable clinical sign. Further research on the BFDV prevalence and transmission (individual–individual, captive–wild and wild–captive) in different bird orders and countries is crucial to understand the dynamics of the viral infection and minimize its impact in captive and wild populations

Psittacine beak and feather disease (PBFD) affects a large number of Psittaciformes species. In this study, five White Cockatoo parrots (Cacatua alba) with clinical signs of PBFD were examined. After euthanasia, a full necropsy of parrots was performed and organs with macroscopic changes were sampled for routine histopathological evaluation. To confirm the presence of psittacine beak and feather disease virus (PBFDv), feather samples were analyzed with the PCR method. Sequence analysis of the obtained PCR products indicated their close relationship (99%) to other PBFDv isolates. Six variable nucleotide sites were discovered, two missense and four silent mutations. This paper presents the evidence of new PBFDv sequence in Cockatoo species.

Psittacine beak and feather disease (PBFD) affects a large number of Psittaciformes species. In this study, five White Cockatoo parrots (Cacatua alba) with clinical signs of PBFD were examined. After euthanasia, a full necropsy of parrots was performed and organs with macroscopic changes were sampled for routine histopathological evaluation. To confirm the presence of psittacine beak and feather disease virus (PBFDv), feather samples were analyzed with the PCR method. Sequence analysis of the obtained PCR products indicated their close relationship (99%) to other PBFDv isolates. Six variable nucleotide sites were discovered, two missense and four silent mutations. This paper presents the evidence of new PBFDv sequence in Cockatoo species.

Psittacine beak and feather disease (PBFD) is a readily recognisable dermatologic condition in wild and captive psittacines worldwide. It is caused by Beak and feather disease virus (BFDV) which is classified in the family Circoviridae and the genus Circovirus. BFDV has a circular ss-DNA genome consisting of seven open reading frames (ORFs), three being conserved in all BFDV isolates, ORF 1 which encodes the Rep protein, ORF 2 which encodes the coat or capsid protein (CP) and ORF 5 which encodes a protein whose function is as yet unknown. General symptoms of the disease include the symmetrical loss of feathers, feather abnormalities, beak and claw deformities, weight loss, anorexia and immunosuppression. The inability to grow BFDV in tissue culture or in embryonated eggs has hindered the routine diagnosis of PBFD affected birds and the development of reliable diagnostic tests and an effective vaccination program. PBFD is widespread in South Africa, leading to a loss of at least 10% of psittacine breeding stocks annually. The disease is also a major threat to the already endangered Cape Parrot (Poicephalus robustus) and the black-cheeked lovebird (Agapornis nigrigenis) and it is only a matter of time before we may see the extinction of these and other parrot species due to the lack of a preventative vaccine. The economical and natural implications of the attack by PBFD led to the aims of the present study which were to develop a potential DNA vaccine candidate, develop an expression system for production of recombinant CP as antigenic protein and establish an enzyme linked immunosorbent assay for the detection of BFDV-specific antibodies in parrots. The entire CP gene which has been suggested to encode for the epitopic protein of the virus was amplified by polymerase chain reaction (PCR) and ligated into a bacterial vector, pBAD/His B or a yeast vector, pKOV136 for expression of recombinant CP in Escherichia coli or Yarrowia lipolytica, respectively. Alternatively, C, National Research Foundation (NRF), National Research Foundation (NRF)