Psittacine Circovirus Infection in Parakeets of the Genus Eunymphicus and Treatment with β-(1,3/1,6)-D-Glucan

Review of psittacine beak and feather disease and its effect on Australian endangered species

BACKGROUND

Since it was first described in the early 1980s, psittacine beak and feather disease (PBFD) has become recognised as the dominant viral pathogen of psittacine birds in Australia. Our aim was to evaluate and review the effect of PBFD and its position as a key threatening process to Australian psittacine bird species. We review the origin/evolutionary pathways and potential threat of PBFD to endangered psittacine bird populations and captive-breeding flocks.

CONCLUSIONS

The most recent beak and feather disease virus (BFDV) phylogenetic analyses indicate that all endangered Australian psittacine bird species are susceptible to, and equally likely to be infected by, BFDV genotypes from a range of host psittacine species. Management of the disease in captive-breeding programs has relied on testing and culling, which has proven costly. The risk of PBFD should be considered very carefully by management teams contemplating the establishment of captive-breeding flocks for endangered species. Alternative disease prevention tools, including vaccination, which are increasingly being used in wildlife health, should be considered more seriously for managing and preventing PBFD in captive flocks of critically endangered species.

Beak and feather disease virus in wild and captive parrots: an analysis of geographic and taxonomic distribution and methodological trends

Psittacine beak and feather disease (PBFD) has emerged in recent years as a major threat to wild parrot populations and is an increasing concern to aviculturists and managers of captive populations. Pathological and serological tests for screening for the presence of beak and feather disease virus (BFDV) are a critical component of efforts to manage the disease and of epidemiological studies. Since the disease was first reported in the mid-1970s, screening for BFDV has been conducted in numerous wild and captive populations. However, at present, there is no current and readily accessible synthesis of screening efforts and their results. Here, we consolidate information collected from 83 PBFD- and BFDV-based publications on the primary screening methods being used and identify important knowledge gaps regarding potential global disease hotspots. We present trends in research intensity in this field and critically discuss advances in screening techniques and their applications to both aviculture and to the management of threatened wild populations. Finally, we provide an overview of estimates of BFDV prevalence in captive and wild flocks alongside a complete list of all psittacine species in which the virus has been confirmed. Our evaluation highlights the need for standardised diagnostic tests and more emphasis on studies of wild populations, particularly in view of the intrinsic connection between global trade in companion birds and the spread of novel BFDV strains into wild populations. Increased emphasis should be placed on the screening of captive and wild parrot populations within their countries of origin across the Americas, Africa and Asia.

Extensive recombination detected among beak and feather disease virus isolates from breeding facilities in Poland

Beak and feather disease virus (BFDV) causes the highly contagious, in some cases fatal, psittacine beak and feather disease in parrots. The European continent has no native parrots, yet in the past has been one of the world's biggest importers of wild-caught exotic parrot species. Following the banning of this practice in 2007, the demand for exotic pet parrots has largely been met by established European breeding facilities, which can also supply buyers outside Europe. However, the years of unregulated importation have provided numerous opportunities for BFDV to enter Europe, meaning the likelihood of birds within captive breeding facilities being BFDV positive is high. This study examined the BFDV status of such facilities in Poland, a country previously shown to have BFDV among captive birds. A total of 209 birds from over 50 captive breeding facilities across Poland were tested, and 43 birds from 18 different facilities tested positive for BFDV. The full BFDV genomes from these 43 positive birds were determined, and phylogenetic analysis revealed that these samples harboured a relatively high degree of diversity and that they were highly recombinant. It is evident that there have been multiple introductions of BFDV into Poland over a long period of time, and the close association of different species of birds in the captive environment has probably facilitated the evolution of new BFDV strains through recombination.

Evidence of multiple introductions of beak and feather disease virus into the Pacific islands of Nouvelle-Calédonie (New Caledonia)

Beak and feather disease virus (BFDV) is a circular ssDNA virus that causes psittacine beak and feather disease and has almost global presence. Here, we report for the first time the presence of in Nouvelle-Calédonie (New Caledonia). One hundred and sixty-eight exotic and 79 endemic birds were sampled in Nouvelle-Calédonie, 26 were found to be positive for BFDV. We characterized the full genomes of 26 isolates and phylogenetic analysis placed nine of the isolates into the BFDV-J strain, with the remaining 17 isolates from Deplanche’s Rainbow Lorikeet (Trichoglossus haematodus deplanchii) forming a novel strain, BFDV-P. Of more concern was the discovery of an infected bird from the vulnerable and endemic New Caledonian Parakeet (Cyanoramphus saisseti). Our results reveal that there have been at least two introductions of BFDV into Nouvelle-Calédonie.