Analysis of the beak and feather disease viral genome indicates the existence of several genotypes which have a complex psittacine host specificity

Abstract

A study was made of the phylogenetic relationships between fifteen complete nucleotide sequences as well as 43 nucleotide sequences of the putative coat protein gene of different strains belonging to the virus species Beak and feather disease virus obtained from 39 individuals of 16 psittacine species. The species included among others, cockatoos ( Cacatuini), African grey parrots ( Psittacus erithacus) and peach-faced lovebirds ( Agapornis roseicollis), which were infected at different geographical locations, within and outside Australia, the native origin of the virus. The derived amino acid sequences of the putative coat protein were highly diverse, with differences between some strains amounting to 50 of the 250 amino acids. Phylogenetic analysis demonstrated that the putative coat gene sequences form six clusters which show a varying degree of psittacine species specificity. Most, but not all strains infecting African grey parrots formed a single cluster as did the strains infecting the cockatoos. Strains infecting the lovebirds clustered with those infecting such Australasian species as Eclectus roratus, Psittacula kramerii and Psephotus haematogaster. Although individual birds included in this study were, where studied, often infected by closely related strains, infection by highly diverged trains was also detected. The possible relationship between BFD viral strains and clinical disease signs is discussed.

Molecular analysis and associated pathology of beak and feather disease virus isolated in Italy from young Congo African grey parrots (Psittacus erithacus) with an “atypical peracute form” of the disease

“…start codon and TAA or TGA as stop codon; and ORF2, which codes for cp gene, was 750 nucleotides in length. The differences in the length of this gene in comparison with the data already published in the literature depend on the start codon that is chosen, since a canonical starting site is not evident (Bassami et al, 1998;de Kloet & de Kloet, 2004;Henriques et al, 2010). Within all of these genomes we identified three conserved amino acid motifs (FTLNN, GTPHLQGY and YCSK), a P-loop for dNTP binding (GPPGCGKS, amino acids 165 to 172) and three additional conserved motifs (WWDGY, amino acids 190 to 194; DDFYGWLP, amino acids 203 to 210; DRYP, amino acids 219 to 222) within the rep gene (Henriques et al, 2010), and the nuclear localization domain (RRRYARPxYRR RHIRRYRLRRRRHFRRRRFxTNRIYTLRxKRQ) on the N-terminus of the CP (Heath et al, 2006).…”

“…In these birds the infection was mainly restricted to Cacatua and Congo African grey parrots (CAGPs), indicating a high susceptibility to BFDV in these two species. Over the years, several classifications have been proposed by different authors (Ritchie et al, 2003;de Kloet & de Kloet, 2004;Heath et al, 2004;Varsani et al, 2011). Following the recent classification system proposed by Varsani et al (2011), the predominant strain circulating in Europe is BFDV-J, a strain isolated mainly from Psittacus erithacus.…”

Relatedness between Host Species and Genotype of Beak and Feather Disease Virus Suggesting Possible Interspecies Cross Infection during Bird Trade

“…Furthermore, there are also no reports for other countries, such as Singapore and Indonesia, which act as the main bases of the bird trade and have many psittacine breeding farms. Therefore, it is necessary epidemiological studies including these countries, and molecular analyses to trace the roots of BFDV genotypes among countries and the relatedness between BFDV sequences and host species as in previous reports [5,6,8,15].…”

“…Genomic analyses of BFDV have been advanced in recent years, and genetic diversity in ORF V1 and C1 has been also reported [2,5,6,8]. Epidemiological studies are still less than other studies, i.e., pathological or etiological studies, although some studies were recently reported in some countries [3,7,12].…”

“…DNA samples were amplified with PBFDdupF (5'-TTG GGT CCT CCT TGT AGT GGG ATC-3') and PBFDdupR (5'-CAG ACG CCG TTT CTC AAC CAA TAG-3'), which were used to amplify a 495-bp fragment corresponding to the part of ORF C1 [14], because genetic clusters were accorded to some psittacine species or subfamily in the phylogenic analysis using BFDV ORF C1 [5,6,11,13,18]. Molecular cloning and sequencing were examined as described previously [11], and at least three clones were sequenced.…”