Beak and feather disease viruses circulating in Cape parrots (Poicepahlus robustus) in South Africa

Abstract

Captive and wild psittacines are vulnerable to the highly contagious psittacine beak and feather disease. The causative agent, beak and feather disease virus (BFDV), was recently detected in the largest remaining population of endangered Cape parrots (Poicepahlus robustus), which are endemic to South Africa. Full-length genomes were isolated and sequenced from 26 blood samples collected from wild and captive Cape parrots to determine possible origins of infection. All sequences had characteristic BFDV sequence motifs and were similar in length to those described in the literature. However, BFDV coat protein (CP) sequences from this study did not contain a previously identified bipartite nuclear localisation signal (NLS) within residues 39-56, which indicates that an alternate NLS is involved in shuttling the CP into the nucleus. Sequences from the wild population shared a high degree of similarity, irrespective of year or location, suggesting that the disease outbreak occurred close to the time when the samples were collected. Phylogenetic analysis of full-length genomes showed that the captive Cape parrot sequences cluster with those isolated from captive-bred budgerigars in KwaZulu-Natal Province, South Africa. Exposure to captive-bred Cape parrots from a breeding facility in KwaZulu-Natal is suggested as a possible source for the virus infection. Phylogenetic analysis of BFDV isolates from wild and captive Cape parrots indicated two separate infection events in different populations, which highlights the potential risk of introducing new strains of the virus into the wild population. The present study represents the first systematic investigation of BFDV virus diversity in the southern-most population of Cape parrots.

Trade and conservation implications of new beak and feather disease virus detection in native and introduced parrots

“…The virus is already present in endemic Cape Parrots ( Poicephalus robustus ) in eastern South Africa (Regnard et al. ), and, although the distribution of Rose‐ringed Parakeets in South Africa does not yet overlap with that of Cape Parrots, their rapid population growth may soon increase the risk of introducing a novel strain to an already‐infected vulnerable endemic species. Consequently, we recommend more intensive surveillance of invasive Rose‐ringed Parakeet populations in South Africa.…”

“…Despite the more thoroughly documented presence of BFDV in threatened wild native parrot populations in South Africa (Regnard et al. ), Mauritius (Kundu et al. ), New Zealand (Jackson et al.…”

Current threats faced by Neotropical parrot populations

“…Since then, Birdlife International has solicited input on threatened species, but information from many parrot experts, including many of the current authors, has not made its way into recent status reviews. Given the rapid development of many anthropogenic threats, such as habitat loss, climate change, and the spread of disease (Hansen et al, 2012(Hansen et al, , 2013Regnard et al, 2015), information compiled over 15 years ago is now unlikely to be valid, and studies based on present day field information are urgently needed.…”

From plant virology to vaccinology: The road less travelled

“…We continue, on sniffs of funding from all over including patent royalties, to try to make vaccines against Beak and feather disease circovirus (BFDV), a ssDNA pathogen of parrots that threatens an endangered local species. 32,33 Finally, we have branched out into reagent-based molecular farming, with the transient production in tobacco of recombinant horseradish peroxidase as a speciality reagent. 34…”