RESUMO
BACKGROUND: Accelerating biodiversity loss necessitates monitoring the potential pathogens of vulnerable species. With a third of New Zealand's avifauna considered at risk of extinction, a greater understanding of the factors that influence microbial transmission in this island ecosystem is needed. We used metatranscriptomics to determine the viruses, as well as other microbial organisms (i.e. the infectomes), of seven bird species, including the once critically endangered black robin (Petroica traversi), on two islands in the remote Chatham Islands archipelago, New Zealand. RESULTS: We identified 19 likely novel avian viruses across nine viral families. Black robins harboured viruses from the Flaviviridae, Herpesviridae, and Picornaviridae, while introduced starlings (Sturnus vulgaris) and migratory seabirds (Procellariiformes) carried viruses from six additional viral families. Potential cross-species virus transmission of a novel passerivirus (family: Picornaviridae) between native (black robins and grey-backed storm petrels) and introduced (starlings) birds was also observed. Additionally, we identified bacterial genera, apicomplexan parasites, as well as a novel megrivirus linked to disease outbreaks in other native New Zealand birds. Notably, island effects were outweighed by host taxonomy as a significant driver of viral composition, even among sedentary birds. CONCLUSIONS: These findings underscore the value of surveillance of avian populations to identify and minimise escalating threats of disease emergence and spread in these island ecosystems. Importantly, they contribute to our understanding of the potential role of introduced and migratory birds in the transmission of microbes and associated diseases, which could impact vulnerable island-endemic species.
Assuntos
Doenças das Aves , Aves , Ilhas , Animais , Nova Zelândia/epidemiologia , Aves/virologia , Doenças das Aves/virologia , Doenças das Aves/transmissão , Doenças das Aves/microbiologia , Doenças das Aves/epidemiologia , Vírus/isolamento & purificação , Vírus/genética , Vírus/classificação , BiodiversidadeRESUMO
BACKGROUND: New Zealand is home to over 120 native endemic species of skinks and geckos that radiated over the last 20-40 million years, likely driven by the exploitation of diverse habitats formed during the Miocene. The recent radiation of animal hosts may facilitate cross-species virus transmission, likely reflecting their close genetic relationships and therefore relatively low barriers for viruses to emerge in new hosts. Conversely, as animal hosts adapt to new niches, even within specific geographic locations, so too could their viruses. Consequently, animals that have niche-specialised following radiations may be expected to harbour genetically distinct viruses. Through a metatranscriptomic analysis of eight of New Zealand's native skink and gecko species, as well as the only introduced lizard species, the rainbow skink (Lampropholis delicata), we aimed to reveal the diversity of viruses in these hosts and determine whether and how the radiation of skinks and geckos in New Zealand has impacted virus diversity and evolution. RESULTS: We identified a total of 15 novel reptilian viruses spanning 11 different viral families, across seven of the nine species sampled. Notably, we detected no viral host-switching among the native animals analysed, even between those sampled from the same geographic location. This is compatible with the idea that host speciation has likely resulted in isolated, niche-constrained viral populations that have prevented cross-species transmission. Using a protein structural similarity-based approach, we further identified a highly divergent bunya-like virus that potentially formed a new family within the Bunyavirales. CONCLUSIONS: This study has broadened our understanding of reptilian viruses within New Zealand and illustrates how niche adaptation may limit viral-host interactions.
Assuntos
Lagartos , Animais , Lagartos/virologia , Nova Zelândia , Vírus/isolamento & purificação , Vírus/genética , FilogeniaRESUMO
The lesser short-tailed bat (Mystacina tuberculata) and the long-tailed bat (Chalinolobus tuberculatus) are Aotearoa New Zealand's only native extant terrestrial mammals and are believed to have migrated from Australia. Long-tailed bats arrived in New Zealand an estimated two million years ago and are closely related to other Australian bat species. Lesser short-tailed bats, in contrast, are the only extant species within the Mystacinidae and are estimated to have been living in isolation in New Zealand for the past 16-18 million years. Throughout this period of isolation, lesser short-tailed bats have become one of the most terrestrial bats in the world. Through a metatranscriptomic analysis of guano samples from eight locations across New Zealand, we aimed to characterise the viromes of New Zealand's bats and determine whether viruses have jumped between these species over the past two million years. High viral richness was observed among long-tailed bats with viruses spanning seven different viral families. In contrast, no bat-specific viruses were identified in lesser short-tailed bats. Both bat species harboured an abundance of likely dietary- and environment-associated viruses. We also identified alphacoronaviruses in long-tailed bat guano that had previously been identified in lesser short-tailed bats, suggesting that these viruses had jumped the species barrier after long-tailed bats migrated to New Zealand. Of note, an alphacoronavirus species discovered here possessed a complete genome of only 22,416 nucleotides with entire deletions or truncations of several non-structural proteins, thereby representing what may be the shortest genome within the Coronaviridae identified to date. Overall, this study has revealed a diverse range of novel viruses harboured by New Zealand's only native terrestrial mammals, in turn expanding our understanding of bat viral dynamics and evolution globally.
RESUMO
First identified in 2002, diphtheritic stomatitis (DS) is a devastating disease affecting yellow-eyed penguins (Megadyptes antipodes, or hoiho in te reo Maori). The disease is associated with oral lesions in chicks and has caused significant morbidity and mortality. DS is widespread among yellow-eyed penguin chicks on mainland New Zealand yet appears to be absent from the subantarctic population. Corynebacterium spp. have previously been suspected as causative agents yet, due to inconsistent cultures and inconclusive pathogenicity, their role in DS is unclear. Herein, we used a metatranscriptomic approach to identify potential causative agents of DS by revealing the presence and abundance of all viruses, bacteria, fungi and protozoa - together, the infectome. Oral and cloacal swab samples were collected from presymptomatic, symptomatic and recovered chicks along with a control group of healthy adults. Two novel viruses from the Picornaviridae were identified, one of which - yellow-eyed penguin megrivirus - was highly abundant in chicks irrespective of health status but not detected in healthy adults. Tissue from biopsied oral lesions also tested positive for the novel megrivirus upon PCR. We found no overall clustering among bacteria, protozoa and fungi communities at the genus level across samples, although Paraclostridium bifermentans was significantly more abundant in oral microbiota of symptomatic chicks compared to other groups. The detection of a novel and highly abundant megrivirus has sparked a new line of inquiry to investigate its potential association with DS.
Assuntos
Picornaviridae , Spheniscidae , Estomatite , Animais , Corynebacterium , Spheniscidae/microbiologia , Spheniscidae/virologia , Estomatite/veterináriaRESUMO
Novel Corynebacterium strains, 3BT and 7BT, were isolated from the oral cavities of young chicks of yellow-eyed penguins (hoiho), Megadyptes antipodes. A polyphasic taxonomic characterization of these strains revealed chemotaxonomic, biochemical and morphological features that are consistent with those of the genus Corynebacterium. The 16S rRNA gene sequence similarity values between the strains and their closest phylogenetic neighbour, Corynebacterium ciconiae CCUG 47525T were 99.07â%, values that are in line with their phylogenomic positions within the evolutionary radiation of the genus Corynebacterium. Digital DNA-DNA hybridization values and average nucleotide identities between the genome sequences of the two strains and related Corynebacterium species were well below the defined threshold values (70 and 95-96â%, respectively) for prokaryotic species delineation. The genome size of these strains varied between 2.45-2.46 Mb with G+C content 62.7-62.9âmol%. Strains 3BT and 7BT were Gram-stain positive bacilli that were able to grow in presence of 0-10â% (w/v) NaCl and at temperature ranging between 20-37 °C. The major fatty acids (>15â%) were C16â:â0 and C18â:â1 ω9c, and the mycolic acid profile included 32-36 carbon atoms. We propose that these strains represent a novel species, Corynebacterium megadyptis sp. nov. with 3BT (=DSM 111184T=NZRM 4755T) as the type strain. Phylogenomically, strains 3BT and 7BT belong to two lineages with subtle differences in MALDI-TOF spectra, chemotaxonomic profiles and phenotypic properties. The fatty acid profile of strain 3BT contains C18â:â0 as a predominant type (>15â%), which is a minor component in strain 7BT. Strain 7BT can oxidize N-acetyl-d-glucosamine, l-serine, α-hydroxy-butyric acid, l-malic acid, l-glutamic acid, bromo-succinic acid and l-lactic acid, characteristics not observed in strain 3BT. Therefore, we propose that these strains represent two subspecies, namely Corynebacterium megadyptis subsp. megadyptis subsp. nov. (type strain, 3BT=DSM 111184T=NZRM 4755T) and Corynebacterium megadyptis subsp. dunedinense subsp. nov. (type strain, 7BT=DSM 111183T=NZRM 4756T).
Assuntos
Ácidos Graxos , Spheniscidae , Animais , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Corynebacterium , Hibridização de Ácido NucleicoRESUMO
Brown kiwi (Apteryx mantelli Bartlett), a ratite endemic to New Zealand, is currently listed as "Vulnerable" under the IUCN classification system due to predation by introduced mammals. Operation Nest Egg (ONE) raises chicks and juveniles in predator-proof enclosures until they are large enough to defend themselves. These facilities experience an environmental accumulation of coccidial oocysts, which leads to severe morbidity and mortality of these kiwi. Four species of coccidia have been morphologically described from sporulated oocysts with additional opportunistic descriptions of endogenous stages. This research continues the morphological descriptions of these species of Eimeria with an additional novel morphotype also morphologically described. It also provides the first genetic characterisation targeting the mitochondrial cytochrome c oxidase I (COI) gene. Based on these findings, it was determined there are at least five morphotypes of Eimeria that infect brown kiwi and co-infections are common at the ONE facilities surveyed. The COI amplicon targeted for this study was sufficient to provide differentiation from other members of this genus. Sanger sequencing yielded ambiguous bases, indicating the need for more in-depth sequencing.
Assuntos
Coccidiose , Eimeria , Paleógnatas , Animais , Eimeria/genética , Especificidade da Espécie , Paleógnatas/genética , Nova Zelândia/epidemiologia , Coccidiose/veterinária , Coccidiose/epidemiologia , MamíferosRESUMO
Toxoplasma gondii has been reported as a cause of morbidity and mortality in New Zealand's native avifauna, including the ground-dwelling Kiwi (Apteryx spp.). To better understand the extent of T. gondii infection in Little Spotted Kiwi (Apteryx owenii), a prevalence survey of kiwi living inside a 200-ha predator-proof mainland ecosanctuary (Zealandia Te Mara a Tane, Wellington, New Zealand) was undertaken. Antibodies to T. gondii were detected by a latex agglutination test (LAT) with a cutoff positive titer of ≥1:64, and T. gondii DNA was detected by PCR. In total, 16/19 (84.2%) birds tested were positive for T. gondii by LAT (10/11), PCR (10/19), or both (4/11). Antibody titers ranged from 1:32 to ≥1:2,048. These results suggest widespread exposure of T. gondii in this population of Little Spotted Kiwi and, in conjunction with earlier reports of toxoplasmosis causing mortality in kiwi, raise important questions as to the effect this parasite may be having on this rare endemic species. Further information on the epidemiology of T. gondii infections within free-living and managed kiwi populations is urgently needed.
Assuntos
Toxoplasma , Toxoplasmose Animal , Animais , Prevalência , Reação em Cadeia da Polimerase/veterinária , Nova Zelândia , Toxoplasmose Animal/epidemiologia , Anticorpos Antiprotozoários , Estudos SoroepidemiológicosRESUMO
Yellow-eyed penguins (Megadyptes antipodes), or hoiho in te reo Maori, are predicted to become extinct on mainland Aotearoa New Zealand in the next few decades, with infectious disease a significant contributor to their decline. A recent disease phenomenon termed respiratory distress syndrome (RDS) causing lung pathology has been identified in very young chicks. To date, no causative pathogens for RDS have been identified. In 2020 and 2021, the number of chick deaths from suspected RDS increased four- and five-fold, respectively, causing mass mortality with an estimated mortality rate of >90%. We aimed to identify possible pathogens responsible for RDS disease impacting these critically endangered yellow-eyed penguins. Total RNA was extracted from tissue samples collected during post-mortem of 43 dead chicks and subject to metatranscriptomic sequencing and histological examination. From these data we identified a novel and highly abundant gyrovirus (Anelloviridae) in 80% of tissue samples. This virus was most closely related to Gyrovirus 8 discovered in a diseased seabird, while other members of the genus Gyrovirus include Chicken anaemia virus, which causes severe disease in juvenile chickens. No other exogenous viral transcripts were identified in these tissues. Due to the high relative abundance of viral reads and its high prevalence in diseased animals, it is likely that this novel gyrovirus is associated with RDS in yellow-eyed penguin chicks.
Assuntos
Vírus da Anemia da Galinha , Gyrovirus , Spheniscidae , Animais , Galinhas , Nova Zelândia/epidemiologiaRESUMO
Yellow-eyed penguins, Megadyptes antipodes, are an endangered species that are endemic to New Zealand. Outbreaks of diphtheritic stomatitis have caused significant mortality for this species, especially among young chicks. In this study, we isolated 16 Corynebacterium sp. isolates from the oral cavities of 2- to 14-day-old chicks at a range of infection stages and sequenced the genomes to understand their virulence mechanisms. Phylogenomic and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) characterization indicate that these strains belong to a novel Corynebacterium species. A simple multiplex PCR-based diagnostic assay has been developed to identify these strains rapidly and reliably. Similar to other corynebacteria, genomic islands and prophages introduced significant diversity among these strains that has potentially led to minor functional variations between the two lineages. Despite the presence of multiple corynebacterial virulence genes and a spaDEF-type pilus gene cluster among these strains, the survival rate was much higher in Galleria mellonella larvae than in those inoculated with Corynebacterium ulcerans NZRM 818 and Corynebacterium pseudotuberculosis NZRM 3004. Therefore, these strains are opportunistic pathogens causing high mortality among young penguin chicks due to a less-developed immune system. IMPORTANCE Yellow-eyed penguins, Megadyptes antipodes, are endangered species with a sharp decline in the numbers of breeding pairs over the last 2 decades. Diphtheritic stomatitis, characterized by a thick fibrinopurulent exudate in the oral cavities and symptoms, including inanition and significant weight loss, is responsible for significant mortality among the young chicks. These chicks are treated with antibiotics, amoxicillin-clavulanic acid or enrofloxacin, but do not always recover from the infection. The pathogen causing these infections and the mechanism of pathogenesis are unclear. This study has identified a novel Corynebacterium species to be associated with diphtheritic stomatitis in yellow-eyed penguins with potential virulence genes that are likely involved in pathogenesis. Importantly, a gene encoding an exotoxin, phospholipase D, is present among these strains. The inactivated form of this enzyme could potentially be used as an effective vaccine to protect these penguins from infection.
RESUMO
Coccidia (Eimeria spp.) in brown kiwi (Apteryx mantelli) cause significant morbidity and mortality in captive rearing facilities. Monitoring the abundance of this parasite in individual birds is crucial for successful management of kiwi. This research compares the abilities of centrifugal faecal flotations (CFF) and a modified Mini-FLOTAC protocol to detect oocysts. We hypothesised that the Mini-FLOTAC would detect higher oocyst counts. Kiwi dropping samples (n = 10) were homogenized in MgSO4 (SG 1.28) and oocyst counts made with CFFs and Mini-FLOTAC counting chambers, with three replicates for each method. For CFF, 0.5 g of droppings were examined using standard methods. Mini-FLOTAC counts were made using a modified sample preparation compared with the manufacturer's protocol but still used a 1:20 dilution of droppings. Oocysts were quantified using light microscopy at ×100-300 magnification. A linear mixed-effects model by REML showed that oocyst per gram estimates via the Mini-FLOTAC method were 3.2 times higher (95% CI 2.4-4.5, p < 0.01) than the CFF results. This increased detection likely represents a more accurate estimation of parasite shedding and should be considered for use in research or applications requiring more accuracy, cost-effectiveness, or accessibility than the CFF provides.
Assuntos
Doenças das Aves/parasitologia , Coccidiose/veterinária , Eimeria/fisiologia , Paleógnatas/parasitologia , Contagem de Ovos de Parasitas/veterinária , Animais , Coccidiose/parasitologia , Fezes/parasitologia , Oocistos/fisiologia , Contagem de Ovos de Parasitas/métodos , Manejo de EspécimesRESUMO
We investigated an epidemic mortality cluster of yellow-eyed penguins (Megadyptes antipodes) that involved 67 moribund or dead birds found on various beaches of the Otago Peninsula, New Zealand, between 21 January and 20 March 2013. Twenty-four carcases were examined post-mortem. Histological lesions of pulmonary, hepatic and splenic erythrophagocytosis and haemosiderosis were found in 23 of 24 birds. Fifteen birds also had haemoglobin-like protein droplets within renal tubular epithelial cells. Despite consistent histological lesions, a cause of death could not be established. Virology, bacteriology and molecular tests for avian influenza, avian paramyxovirus-1, avipoxvirus, Chlamydia psittaci, Plasmodium spp., Babesia spp., Leucocytozoon spp. and Toxoplasma gondii were negative. Tissue concentrations of a range of heavy metals (n = 4 birds) were consistent with low level exposure, while examination of proventricular contents and mucus failed to detect any marine biotoxins or Clostridium botulinum toxin. Hepatic concentrations of total polycyclic aromatic hydrocarbons (PAHs) (n = 5 birds) were similar to background concentrations of polycyclic aromatic hydrocarbons previously found in yellow-eyed penguins from the South Island of New Zealand, but there were significantly higher concentrations of 1-methylnapthelene and 2-methylnapthelene in the birds found dead in this mortality cluster. The biological significance of this finding is unclear. A temporal investigation of the epidemic did not indicate either a common source or propagative epidemic pattern. Although our investigation did not definitively implicate a toxic or infectious agent, we could not rule out causes such as toxic marine organisms or mycoplasmosis. Further investigations should therefore by carried out in the event of future mortality clusters.
Assuntos
Doenças das Aves/epidemiologia , Spheniscidae , Animais , Doenças das Aves/diagnóstico , Doenças das Aves/mortalidade , Doenças das Aves/patologia , Espécies em Perigo de Extinção , Feminino , Hidrocarbonetos Cíclicos/análise , Fígado/metabolismo , Masculino , Metais Pesados/análise , Camundongos , Nova Zelândia/epidemiologia , Proventrículo , Análise Espaço-TemporalRESUMO
Conservation translocations are increasingly used to manage threatened species and restore ecosystems. Translocations increase the risk of disease outbreaks in the translocated and recipient populations. Qualitative disease risk analyses have been used as a means of assessing the magnitude of any effect of disease and the probability of the disease occurring associated with a translocation. Currently multiple alternative qualitative disease risk analysis packages are available to practitioners. Here we compare the ease of use, expertise required, transparency, and results from, three different qualitative disease risk analyses using a translocation of the endangered New Zealand passerine, the hihi (Notiomystis cincta), as a model. We show that the three methods use fundamentally different approaches to define hazards. Different methods are used to produce estimations of the risk from disease, and the estimations are different for the same hazards. Transparency of the process varies between methods from no referencing, or explanations of evidence to justify decisions, through to full documentation of resources, decisions and assumptions made. Evidence to support decisions on estimation of risk from disease is important, to enable knowledge acquired in the future, for example, from translocation outcome, to be used to improve the risk estimation for future translocations. Information documenting each disease risk analysis differs along with variation in emphasis of the questions asked within each package. The expertise required to commence a disease risk analysis varies and an action flow chart tailored for the non-wildlife health specialist are included in one method but completion of the disease risk analysis requires wildlife health specialists with epidemiological and pathological knowledge in all three methods. We show that disease risk analysis package choice may play a greater role in the overall risk estimation of the effect of disease on animal populations involved in a translocation than might previously have been realised.
Assuntos
Doenças dos Animais , Conservação dos Recursos Naturais , Animais , Animais Selvagens , Espécies em Perigo de Extinção , Nova Zelândia , Passeriformes , Medição de RiscoRESUMO
Circoviruses are circular, non-enveloped, single-stranded DNA viruses around 2000 nucleotides (nt) in length and include the pathogenic species, Porcine circovirus 1 and Beak and feather disease virus, capable of causing significant morbidity and mortality. This group of viruses may be robust to degradation by external environments, and avian circoviruses are known to move between closely related hosts. Using a de novo metagenomic approach, followed by confirmatory PCR, we identify for the first time a circular Rep-encoding single-stranded (CRESS) DNA virus in New Zealand kiwi, Apteryx spp., derived from faecal matter of the rowi kiwi (A. rowi) showing signs of verminous dermatitis. The entire 2085 nt genome was cloned and sequenced and contains both capsid and replicase genes, as well as a conserved 9 nt motif. Phylogenetic analyses place it within Circoviridae, adjacent to other environmental CRESS-DNA viruses, and most closely related to badger circovirus-like virus (Meles meles circovirus-like virus). As the rowi is the most critically endangered kiwi, it is vital to understand the role of rowi kiwi circovirus-like virus as a possible pathogen and also any potential cross-species transmission.
Assuntos
Infecções por Circoviridae/virologia , Circovirus/genética , Genoma Viral/genética , Paleógnatas/virologia , Animais , Proteínas do Capsídeo/genética , Circoviridae/genética , DNA de Cadeia Simples/genética , DNA Viral/genética , Nova Zelândia , Fases de Leitura Aberta/genética , FilogeniaRESUMO
Beak and feather disease virus (BFDV) is a single-stranded DNA virus that is the etiological agent of beak and feather disease in both wild and captive parrots. Given that BFDV is globally recognized as a conservation threat for wild parrots, between 2011-2013, red-crowned parakeets (Cyanoramphus novaezelandiae, n = 229), which are endemic to New Zealand, were captured in mist nets on Tiritiri Matangi Island and Hauturu-o-Toi/Little Barrier Island (LBI), New Zealand, for disease surveillance. Blood and feathers from all birds were tested by PCR for BFDV, and full genomes were recovered and sequenced. A subset of blood samples (n = 96) were tested for antibodies to BFDV by the haemagglutination inhibition (HI) test. A further 238 feather samples were obtained from red-crowned parakeets from three sites in the Wellington region of the North Island, and these were screened for BFDV. The DNA-based prevalence of BFDV infection determined on Tiritiri Matangi Island was 1.09% (CI 95 %, 0.1-3.9%); on Hauturu-o-Toi/LBI, 4.4% (95% CI, 0.5%-15.1%); on Kapiti Island, 3.4% (CI 95%, 1.1-7.8%); at the ZEALANDIA-Karori sanctuary, 1.6% (95% CI, 0-8.4%); and on Matiu-Somes Island, 0% (CI 95%, 0-12.3%). Seroprevalence for BFDV, indicating prior or current exposure, in the Tiritiri Matangi Island population, it was 2% (CI 95%, 0-10.1%), and in the Hauturu-o-Toi/LBI population was 14% (CI 95%, 5.3-27.9%). BFDV-positive birds showed no signs of clinical disease, with the exception of an individual bird obtained opportunistically from Shakespear Regional Park during the study period, which had classical signs of feather loss. Phylogenetic analysis of the 11 full genome sequences recovered from BFDV-positive red-crowned parakeets revealed evidence of ongoing viral flow between red-crowned parakeets and eastern rosellas (Platycercus eximius) in the Hauraki Gulf/Auckland region, with separate but closely related strains from the Wellington region of the North Island. This is the first study to report HI results for a New Zealand endemic parrot species, and the first epidemiological analysis of serial cross-sectional surveys in a BFDV-infected population of red-crowned parakeets in New Zealand. We postulate that although BFDV remains a threat to small, isolated or naïve populations of parrots globally, the low viral prevalence in this and other studies suggests that native parakeets in New Zealand may act as dead-end or spillover hosts.
Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Infecções por Circoviridae/veterinária , Circovirus/isolamento & purificação , Doenças Transmissíveis Emergentes/veterinária , Periquitos/virologia , Animais , Anticorpos Antivirais/sangue , Sangue/virologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Estudos Transversais , Plumas/virologia , Feminino , Genoma Viral , Testes de Inibição da Hemaglutinação , Masculino , Dados de Sequência Molecular , Nova Zelândia/epidemiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Estudos SoroepidemiológicosRESUMO
Bats harbour a diverse array of viruses, including significant human pathogens. Extensive metagenomic studies of material from bats, in particular guano, have revealed a large number of novel or divergent viral taxa that were previously unknown. New Zealand has only two extant indigenous terrestrial mammals, which are both bats, Mystacina tuberculata (the lesser short-tailed bat) and Chalinolobus tuberculatus (the long-tailed bat). Until the human introduction of exotic mammals, these species had been isolated from all other terrestrial mammals for over 1 million years (potentially over 16 million years for M. tuberculata). Four bat guano samples were collected from M. tuberculata roosts on the isolated offshore island of Whenua hou (Codfish Island) in New Zealand. Metagenomic analysis revealed that this species still hosts a plethora of divergent viruses. Whilst the majority of viruses detected were likely to be of dietary origin, some putative vertebrate virus sequences were identified. Papillomavirus, polyomavirus, calicivirus and hepevirus were found in the metagenomic data and subsequently confirmed using independent PCR assays and sequencing. The new hepevirus and calicivirus sequences may represent new genera within these viral families. Our findings may provide an insight into the origins of viral families, given their detection in an isolated host species.
Assuntos
Quirópteros/virologia , Vírus/isolamento & purificação , Animais , Espécies em Perigo de Extinção , Genoma Viral , Metagenômica , Dados de Sequência Molecular , Nova Zelândia , Filogenia , Proteínas Virais/genética , Vírus/classificação , Vírus/genéticaRESUMO
Because of recent interest in bats as reservoirs of emerging diseases, we investigated the presence of viruses in Mystacina tuberculata bats in New Zealand. A novel alphacoronavirus sequence was detected in guano from roosts of M. tuberculata bats in pristine indigenous forest on a remote offshore island (Codfish Island).
Assuntos
Quirópteros/virologia , Vírus/genética , Vírus/isolamento & purificação , Animais , Nova Zelândia , FilogeniaRESUMO
Beak and feather disease virus (BFDV) infections are often fatal to both captive and wild parrot populations. Its recent discovery in a wild population of native red-fronted parakeets has raised concerns for the conservation of native parrots, all of which are threatened or endangered. The question of a recent introduction versus a native genotype of the virus poses different conservation-management challenges, and thus, a clear understanding of the molecular phylogeny of BDFV is a crucial step towards integrated management planning. This study represents the first comprehensive attempt to screen New Zealand's endangered and threatened psittacines systematically for BFDV. We sampled and screened kakapos (Strigops habroptilus), kakas (Nestor meridionalis), keas (N. notabilis), Chatham parakeets (Cyanoramphus forbesi), Malherbe's parakeets (Cyanoramphus malherbi), yellow-crowned parakeets (C. auriceps) and red-fronted parakeets (Cyanoramphus novaezelandiae), as well as eastern rosellas (Platycercus eximius), an introduced species that is now common throughout the North Island, for BFDV. Out of all species and populations sampled (786 individuals), we found 16 BFDV-positive red-fronted parakeets from Little Barrier Island/Hauturu, seven eastern rosellas from the Auckland region, and eight yellow-crowned parakeets from the Eglinton Valley in the South Island. The full genomes of the viral isolates from the red-fronted parakeets share 95-97 % sequence identity to those from the invasive eastern rosellas and 92.7-93.4 % to those isolates from the South Island yellow-crowned parakeets. The yellow-crowned parakeet BFDV isolates share 92-94 % sequence identity with those from eastern rosellas. The low level of diversity among all BFDV isolates from red-fronted parakeets could suggest a more recent infection among these birds compared to the yellow-crowned parakeets, whereas the diversity in the eastern rosellas indicates a much more established infection. Pro-active screening and monitoring of BFDV infection rates in aviaries as well as in wild populations are necessary to limit the risk of transmission among threatened and endangered parrot populations in New Zealand.
Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Infecções por Circoviridae/veterinária , Circovirus/classificação , Circovirus/genética , Animais , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/virologia , Circovirus/isolamento & purificação , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Variação Genética , Genoma Viral , Dados de Sequência Molecular , Nova Zelândia/epidemiologia , Papagaios , Filogenia , Análise de Sequência de DNARESUMO
Kea (Nestor notabilis) are high country parrots endemic to New Zealand. The foraging behavior and inquisitive nature of Kea have led to incidences of foreign substance ingestion, including lead. Between April 2006 and November 2007, 38 Kea in Aoraki/Mount Cook National Park, New Zealand, were captured, and blood was sampled for blood lead analysis. All birds sampled had detectable blood lead with concentrations ranging from 0.028 mg/l to 3.43 mg/l (mean+/-SE, 0.428+/-0.581 mg/l). A retrospective analysis of necropsy reports and archived samples from 15 wild Kea from various South Island locations also was carried out. Seven of these birds (five from the Aoraki/Mount Cook area) died with clinical signs consistent with lead toxicosis and had liver and/or kidney lead levels reported to cause lead toxicity in other avian species. All seven of these birds also had lead inclusions (Ziehl-Neelson positive intranuclear inclusion bodies) in the renal tubular epithelial cells. These are considered diagnostic of lead toxicity in other species. This study showed that lead exposure is ubiquitous in the sampled population and may be an important contributing factor in Kea morbidity and mortality. As a result of these findings, lead abatement in areas frequented by Kea is being initiated.
Assuntos
Doenças das Aves/mortalidade , Exposição Ambiental , Intoxicação por Chumbo/veterinária , Chumbo/sangue , Papagaios/metabolismo , Animais , Animais Selvagens/sangue , Animais Selvagens/metabolismo , Comportamento Animal , Doenças das Aves/epidemiologia , Feminino , Corpos de Inclusão/química , Intoxicação por Chumbo/epidemiologia , Intoxicação por Chumbo/mortalidade , Masculino , Nova Zelândia/epidemiologia , Papagaios/sangue , Estudos RetrospectivosRESUMO
Psittacine beak and feather disease (PBFD) is a viral disease distributed worldwide with a potentially critical impact on many rare parrots. While efforts have been made to determine its prevalence in wild and captive psittacines, only limited work has been done to document complete genomes of its causative agent, beak and feather disease virus (BFDV). Here, we describe five full genomes of BFDV isolated from wild specimens of an endemic New Zealand parrot, the red-fronted parakeet (Cyanoramphus novaezelandiae). The isolates share >99% nucleotide similarity amongst themselves and approximately 91-92% similarity to BFDV isolates from southern Africa, Europe and Australia. A maximum-likelihood (ML) phylogenetic tree including 42 other full-genome sequences indicated that the five isolates from red-fronted parakeets represent an undescribed genotype of BFDV. These isolates are evolutionarily most closely related to the Cacatuini isolates from Thailand and the Lorinae isolates from Australia in the rep gene ML tree; however, in the cp ML tree, the evolutionary relationship is closer to viruses found in the Psittacini.