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1.
J Vet Med Educ ; 47(s1): 92-98, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33074077

RESUMO

As part of an OIE Veterinary Education Twinning Project linking The University of Queensland, Australia and Nong Lam University, Vietnam, the limited access to animal and clinical resources was identified as an impediment to high quality veterinary education at Nong Lam University. However, student focused, simulated learning spaces, which have been widely adopted in veterinary training, are a cost-effective opportunity to provide initial clinical skills to students in countries where resourcing is constrained. In clinical skills training facilities, students use models and simulators to practice their clinical skills to develop the confidence, competence and muscle memory to enter the clinical phase of their training. While high-fidelity veterinary simulators and models are expensive, effective models for foundational clinical skills development can be built in-house for students to practice their skills authentically. This article outlines the cost effective establishment of a veterinary clinical skills training facility at Nong Lam University.


Assuntos
Competência Clínica , Educação em Veterinária , Animais , Austrália , Países em Desenvolvimento , Humanos , Estudantes
2.
J Vet Med Educ ; 47(s1): 83-91, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32530797

RESUMO

A World Organisation for Animal Health (OIE) Veterinary Education Twinning Project was established between the veterinary schools at Nong Lam University (NLU) in Ho Chi Minh City, Vietnam, and the University of Queensland, Gatton, Australia, as part of the scheme established to promote high-quality veterinary services through improved veterinary education. Included in the partnership's primary aims were building the capacity of veterinary teaching staff with respect to general teaching practice and also in response to identified deficiency areas, and to develop outcome assessment processes. One challenge facing the project was the different approaches and experiences of teaching and learning for the faculty and students between the two widely different historical and cultural contexts of Australia and Vietnam. The project enhanced the pedagogy capability in NLU faculty and introduced student-focused approaches to teaching. The NLU staff involved in the project strongly embraced a student-centered approach to learning and case-based teaching in particular, adopting these strategies in their own teaching. An analysis of students' approach to learning demonstrates that the majority preferred a deep approach to learning and that these students valued case studies, problem-solving exercises, and working in small groups during teaching sessions more than students who took a surface approach to learning. An improved recognition of the ways the Vietnamese students approach their learning in their home country will guide future teaching design, as well as give insight into the approaches to teaching for Southeast Asian students within the Australian veterinary science programs.


Assuntos
Educação em Veterinária , Condicionamento Físico Animal , Animais , Austrália , Faculdades de Medicina Veterinária , Ensino , Vietnã
3.
J Anim Ecol ; 88(11): 1696-1707, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31297802

RESUMO

Social network analysis has been postulated as a tool to study potential pathogen transmission in wildlife but is resource-intensive to quantify. Networks based on bacterial genotypes have been proposed as a cost-effective method for estimating social or transmission network based on the assumption that individuals in close contact will share commensal bacteria. However, the use of network analysis to study wild populations requires critical evaluation of the assumptions and parameters these models are founded on. We test (a) whether networks of commensal bacterial sharing are related to hosts' social associations and hence could act as a proxy for estimating transmission networks, (b) how the parameters chosen to define host associations and delineate bacterial genotypes impact inference and (c) whether these relationships change across time. We use stochastic simulations to evaluate how uncertainty in parameter choice affects network structure. We focused on a well-studied population of eastern grey kangaroos (Macropus giganteus), from Sundown National Park, Australia. Using natural markings, each individual was identified and its associations with other kangaroos recorded through direct field observations over 2 years to construct social networks. Faecal samples were collected, Escherichia coli was cultured and genotyped using BOX-PCR, and bacterial networks were constructed. Two individuals were connected in the bacterial network if they shared at least one E. coli genotype. We determined the capacity of bacterial networks to predict the observed social network structure in each year. We found little support for a relationship between social association and dyadic commensal bacterial similarity. Thresholds to determine host associations and similarity cut-off values used to define E. coli genotypes had important ramifications for inferring links between individuals. In fact, we found that inferences can show opposite patterns based on the chosen thresholds. Moreover, no similarity in overall bacterial network structure was detected between years. Although empirical disease transmission data are often unavailable in wildlife populations, both bacterial networks and social networks have limitations in representing the mode of transmission of a pathogen. Our results suggest that caution is needed when designing such studies and interpreting results.


El análisis de redes sociales se ha postulado como una herramienta para estudiar la potencial transmisión de patógenos en fauna silvestre. Sin embargo, las redes sociales en fauna silvestre son difíciles de cuantificar. Es por esto que las redes basadas en el genotipo bacteriano se han propuesto como un método más rentable para estimar redes sociales o de transmisión, basado en el supuesto de que individuos en contacto cercano compartirán bacterias comensales. Sin embargo, el uso del análisis de redes para estudiar poblaciones silvestres requiere una evaluación crítica de los supuestos y parámetros en los que se basan estos métodos. En este estudio probamos (a) si las redes de bacterias comensales están relacionadas con las redes sociales y por lo tanto podrían actuar como proxy para estimar redes de transmisión. Exploramos (b) cómo los parámetros elegidos, para definir asociaciones entre individuos y delinear genotipos bacterianos, impactan en los resultados. Finalmente, examinamos (c) si estas relaciones cambian con el tiempo. Utilizamos simulaciones estocásticas para evaluar cómo la incertidumbre en la elección de parámetros afecta la estructura de la red. Nuestro estudio se basó en una población de canguros grises (Macropus giganteus), del Parque Nacional de Sundown, Australia. Cada individuo fue identificado usando marcas naturales, y sus interacciones con otros canguros se registraron a través de observaciones de campo durante dos años para construir redes sociales. Se recolectaron muestras fecales, se cultivó Escherichia coli, se determinó el genotipo mediante BOX-PCR y se construyeron las redes bacterianas. El criterio para conectar dos individuos en la red bacteriana, se basa en sí al menos un genotipo de E. coli es compartido entre dos individuos. Determinamos la capacidad de las redes bacterianas para predecir la estructura de las redes sociales observadas en cada año. Encontramos poca evidencia que sustente una relación entre la asociación social y la similitud bacteriana. Los umbrales, que determinan las asociaciones entre individuos en las redes sociales y los valores de corte de similitud para definir los genotipos de E. coli, tuvieron una importante influencia para inferir vínculos entre individuos. De hecho, encontramos que las inferencias pueden mostrar patrones opuestos dependiendo de los umbrales elegidos. Además, no se detectó similitud en la estructura de la red bacteriana general entre los años. Aunque los datos empíricos de transmisión de enfermedades a menudo no están disponibles para poblaciones de vida silvestre, los análisis de redes pueden potencialmente solventar dicho problema. Sin embargo, tanto las redes bacterianas como las redes sociales tienen limitaciones para representar el modo de transmisión de un patógeno. Nuestros resultados sugieren que se necesita tener cautela al diseñar este tipo de estudios e interpretar los resultados.


Assuntos
Escherichia coli , Macropodidae , Animais , Animais Selvagens , Austrália , Bactérias
4.
Proc Natl Acad Sci U S A ; 110(42): 16772-7, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24082133

RESUMO

We aimed to describe the evolution of resistance to amitraz in Rhipicephalus microplus in the field and to test the association between amitraz resistance and the frequency of a mutation in the ß-adrenergic octopamine receptor gene (RmßAOR). We established six populations of Rhipicephalus microplus ticks in similar paddocks by the admixture of ticks from strains known to be susceptible and resistant to amitraz and synthetic pyrethroids. Each population was managed using one of three acaricide treatment regimes: always amitraz, always spinosad, or rotation between amitraz and spinosad. We used microsatellites to elucidate population structure over time, an SNP in the para-sodium channel gene previously demonstrated to confer resistance to synthetic pyrethroids to quantify changes in resistance to synthetic pyrethroids over time, and a nonsynonymous SNP in the RmßAOR, a gene that we proposed to confer resistance to amitraz, to determine whether selection with amitraz increased the frequency of this mutation. The study showed panmixia of the two strains and that selection of ticks with amitraz increased the frequency of the RmßAOR mutation while increasing the prevalence of amitraz-resistance. We conclude that polymorphisms in the RmßAOR gene are likely to confer resistance to amitraz.


Assuntos
Proteínas de Artrópodes , Resistência a Medicamentos , Inseticidas/farmacologia , Mutação , Receptores de Amina Biogênica , Rhipicephalus , Toluidinas/farmacologia , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Bovinos , Combinação de Medicamentos , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Genes , Macrolídeos/farmacologia , Polimorfismo de Nucleotídeo Único , Receptores de Amina Biogênica/genética , Receptores de Amina Biogênica/metabolismo , Rhipicephalus/genética , Rhipicephalus/metabolismo
5.
FEMS Microbiol Ecol ; 100(6)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38658192

RESUMO

Gut bacterial communities play a vital role in a host's digestion and fermentation of complex carbohydrates, absorption of nutrients, and energy harvest/storage. Dugongs are obligate seagrass grazers with an expanded hindgut and associated microbiome. Here, we characterised and compared the faecal bacterial communities of dugongs from genetically distinct populations along the east coast of Australia, between subtropical Moreton Bay and tropical Cleveland Bay. Amplicon sequencing of fresh dugong faecal samples (n=47) revealed Firmicutes (62%) dominating the faecal bacterial communities across all populations. Several bacterial genera (Bacteroides, Clostridium sensu stricto 1, Blautia and Polaribacter) were detected in samples from all locations, suggesting their importance in seagrass digestion. Principal coordinate analysis showed the three southern-most dugong populations having different faecal bacterial community compositions from northern populations. The relative abundances of the genera Clostridium sensu stricto 13 and dgA-11 gut group were higher, but Bacteroides was lower, in the southern dugong populations, compared to the northern populations, suggesting potential adaptive changes associated with location. This study contributes to our knowledge of the faecal bacterial communities of dugongs inhabiting Australian coastal waters. Future studies of diet selection in relation to seagrass availability throughout the dugong's range will help to advance our understanding of the roles that seagrass species may play in affecting the dugong's faecal bacterial community composition.


Assuntos
Bactérias , Dugong , Fezes , Microbioma Gastrointestinal , Fezes/microbiologia , Austrália , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Microbioma Gastrointestinal/genética , Animais , Dugong/genética , RNA Ribossômico 16S/genética , DNA Bacteriano/genética
6.
Evolution ; 78(6): 1183-1192, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38457362

RESUMO

Body size is a key morphological attribute, often used to delimit species boundaries among closely related taxa. But body size can evolve in parallel, reaching similar final states despite independent evolutionary and geographic origins, leading to faulty assumptions of evolutionary history. Here, we document parallel evolution in body size in the widely distributed leaf-nosed bat genus Hipposideros, which has misled both taxonomic and evolutionary inference. We sequenced reduced representation genomic loci and measured external morphological characters from three closely related species from the Solomon Islands archipelago, delimited by body size. Species tree reconstruction confirms the paraphyly of two morphologically designated species. The nonsister relationship between large-bodied H. dinops lineages found on different islands indicates that large-bodied ecomorphs have evolved independently at least twice in the history of this radiation. A lack of evidence for gene flow between sympatric, closely related taxa suggests the rapid evolution of strong reproductive isolating barriers between morphologically distinct populations. Our results position Solomon Islands Hipposideros as a novel vertebrate system for studying the repeatability of parallel evolution under natural conditions. We conclude by offering testable hypotheses for how geography and ecology could be mediating the repeated evolution of large-bodied Hipposideros lineages in the Solomon Islands.


Assuntos
Quirópteros , Animais , Quirópteros/genética , Quirópteros/anatomia & histologia , Quirópteros/classificação , Melanesia , Tamanho Corporal , Evolução Biológica , Filogenia , Fluxo Gênico
7.
Mol Ecol ; 21(18): 4472-85, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22882348

RESUMO

Highly mobile marine species in areas with no obvious geographic barriers are expected to show low levels of genetic differentiation. However, small-scale variation in habitat may lead to resource polymorphisms and drive local differentiation by adaptive divergence. Using nuclear microsatellite genotyping at 20 loci, and mitochondrial control region sequencing, we investigated fine-scale population structuring of inshore bottlenose dolphins (Tursiops aduncus) inhabiting a range of habitats in and around Moreton Bay, Australia. Bayesian structure analysis identified two genetic clusters within Moreton Bay, with evidence of admixture between them (F(ST) = 0.05, P = 0.001). There was only weak isolation by distance but one cluster of dolphins was more likely to be found in shallow southern areas and the other in the deeper waters of the central northern bay. In further analysis removing admixed individuals, southern dolphins appeared genetically restricted with lower levels of variation (AR = 3.252, π = 0.003) and high mean relatedness (r = 0.239) between individuals. In contrast, northern dolphins were more diverse (AR = 4.850, π = 0.009) and were mixing with a group of dolphins outside the bay (microsatellite-based STRUCTURE analysis), which appears to have historically been distinct from the bay dolphins (mtDNA Φ(ST) = 0.272, P < 0.001). This study demonstrates the ability of genetic techniques to expose fine-scale patterns of population structure and explore their origins and mechanisms. A complex variety of inter-related factors including local habitat variation, differential resource use, social behaviour and learning, and anthropogenic disturbances are likely to have played a role in driving fine-scale population structure among bottlenose dolphins in Moreton Bay.


Assuntos
Golfinho Nariz-de-Garrafa/genética , Genética Populacional , Animais , Austrália , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Ecossistema , Feminino , Variação Genética , Técnicas de Genotipagem , Haplótipos , Masculino , Repetições de Microssatélites , Dados de Sequência Molecular , Análise de Sequência de DNA
8.
Mol Phylogenet Evol ; 65(3): 831-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22940151

RESUMO

Major climatic oscillations since the mid-Miocene climatic optimum are known to have played a key role in promoting speciation events. In this study we use molecular data to elucidate the evolutionary history of Galerella nigrata and link its divergence to known major climatic events. A total of 51 samples from G. nigrata and 17 from Galerella sanguinea were used to provide the first molecular evidence that G. nigrata may be a species in its own right. Both mitochondrial cytochrome b and the nuclear ß-fibrinogen intron seven sequences of G. nigrata form distinct monophyletic clades, separate from its sister species G. sanguinea. We estimate the divergence of these two species to have occurred 3.85-4.27 million years ago, coinciding with a period of the Plio-Pleistocene that was characterised by cooling global temperatures and strong aridity in southern Africa. However, evidence for potential hybridization between the two species was documented for ten individuals using phenotypic (pelage colouration) and/or molecular (nuclear and mtDNA sequences and microsatellite loci) data. There appeared to be a bias towards unidirectional hybridization with all potential hybrids showing mtDNA haplotypes from G. nigrata. We suggest that as the desert expanded across Namibia, G. sanguinea likely retreated with the savanna, leaving some mongooses stranded on the granite inselbergs of north-western Namibia. Subsequent adaptation of these mongooses to local conditions on granite inselbergs could have led to ecological speciation. Secondary contact zones would have been re-established with subsequent global warming events. It appears that the two species have not yet undergone complete reproductive isolation.


Assuntos
Evolução Molecular , Especiação Genética , Herpestidae/genética , Hibridização Genética , Filogenia , África Austral , Animais , Mudança Climática , DNA Mitocondrial/genética , Feminino , Genética Populacional , Genótipo , Haplótipos , Herpestidae/classificação , Íntrons , Masculino , Namíbia , Isolamento Reprodutivo , Análise de Sequência de DNA
9.
BMC Vet Res ; 8: 202, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23107143

RESUMO

BACKGROUND: Congenital hereditary sensorineural deafness (CHSD) occurs in many dog breeds, including Australian Cattle Dogs. In some breeds, CHSD is associated with a lack of cochlear melanocytes in the stria vascularis, certain coat characteristics, and potentially, abnormalities in neuroepithelial pigment production. This study investigates phenotypic markers for CHSD in 899 Australian Cattle Dogs. RESULTS: Auditory function was tested in 899 Australian Cattle Dogs in family groups using brainstem auditory evoked response testing. Coat colour and patterns, facial and body markings, gender and parental hearing status were recorded.Deafness prevalence among all 899 dogs was 10.8% with 7.5% unilaterally deaf, and 3.3% bilaterally deaf, and amongst pups from completely tested litters (n = 696) was 11.1%, with 7.5% unilaterally deaf, and 3.6% bilaterally deaf.Univariable and multivariable analyses revealed a negative association between deafness and bilateral facial masks (odds ratio 0.2; P ≤ 0.001). Using multivariable logistic animal modelling, the risk of deafness was lower in dogs with pigmented body spots (odds ratio 0.4; P = 0.050).No significant associations were found between deafness and coat colour.Within unilaterally deaf dogs with unilateral facial masks, no association was observed between the side of deafness and side of mask. The side of unilateral deafness was not significantly clustered amongst unilaterally deaf dogs from the same litter. Females were at increased risk of deafness (odds ratio from a logistic animal model 1.9; P = 0.034) after adjusting for any confounding by mask type and pigmented body spots. CONCLUSIONS: Australian Cattle Dogs suffer from CHSD, and this disease is more common in dogs with mask-free faces, and in those without pigmented body patches. In unilaterally deaf dogs with unilateral masks, the lack of observed association between side of deafness and side of mask suggests that if CHSD is due to defects in molecular pigment pathways, the molecular control of embryonic melanoblast migration from ectoderm to skin differs from control of migration from ectoderm to cochlea. In Australian Cattle Dogs, CHSD may be more common in females.


Assuntos
Doenças do Cão/congênito , Cabelo/fisiologia , Perda Auditiva Neurossensorial/veterinária , Pigmentos Biológicos/genética , Animais , Cães , Feminino , Perda Auditiva Neurossensorial/congênito , Modelos Logísticos , Masculino , Análise Multivariada , Pigmentos Biológicos/fisiologia , Fatores de Risco , Fatores Sexuais
10.
Genes (Basel) ; 12(4)2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33805165

RESUMO

Congenital deafness is prevalent among modern dog breeds, including Australian Stumpy Tail Cattle Dogs (ASCD). However, in ASCD, no causative gene has been identified so far. Therefore, we performed a genome-wide association study (GWAS) and whole genome sequencing (WGS) of affected and normal individuals. For GWAS, 3 bilateral deaf ASCDs, 43 herding dogs, and one unaffected ASCD were used, resulting in 13 significantly associated loci on 6 chromosomes, i.e., CFA3, 8, 17, 23, 28, and 37. CFA37 harbored a region with the most significant association (-log10(9.54 × 10-21) = 20.02) as well as 7 of the 13 associated loci. For whole genome sequencing, the same three affected ASCDs and one unaffected ASCD were used. The WGS data were compared with 722 canine controls and filtered for protein coding and non-synonymous variants, resulting in four missense variants present only in the affected dogs. Using effect prediction tools, two variants remained with predicted deleterious effects within the Heart development protein with EGF like domains 1 (HEG1) gene (NC_006615.3: g.28028412G>C; XP_022269716.1: p.His531Asp) and Kruppel-like factor 7 (KLF7) gene (NC_006619.3: g.15562684G>A; XP_022270984.1: p.Leu173Phe). Due to its function as a regulator in heart and vessel formation and cardiovascular development, HEG1 was excluded as a candidate gene. On the other hand, KLF7 plays a crucial role in the nervous system, is expressed in the otic placode, and is reported to be involved in inner ear development. 55 additional ASCD samples (28 deaf and 27 normal hearing dogs) were genotyped for the KLF7 variant, and the variant remained significantly associated with deafness in ASCD (p = 0.014). Furthermore, 24 dogs with heterozygous or homozygous mutations were detected, including 18 deaf dogs. The penetrance was calculated to be 0.75, which is in agreement with previous reports. In conclusion, KLF7 is a promising candidate gene causative for ASCD deafness.


Assuntos
Doenças do Cão/congênito , Perda Auditiva Neurossensorial/veterinária , Fatores de Transcrição Kruppel-Like/genética , Mutação de Sentido Incorreto , Sequenciamento Completo do Genoma/veterinária , Animais , Austrália , Doenças do Cão/genética , Cães , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/veterinária , Perda Auditiva Neurossensorial/congênito , Perda Auditiva Neurossensorial/genética , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Penetrância
11.
Mol Phylogenet Evol ; 57(3): 1134-48, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20727976

RESUMO

Australia and New Guinea share a common biogeographical history and unique vertebrate fauna. Investigation of genetic relationships among the wet forest-restricted pademelons (Macropodidae: Thylogale) provides insight into the historical connections between the two regions and the evolution of the Australasian marsupial fauna. Molecular phylogenetic relationships among Thylogale species were analysed using mitochondrial (12S rRNA and cytochrome b) and nuclear (omega-globin intron) sequence data with Bayesian and maximum likelihood methods. Australian species were resolved as well-supported, monophyletic clades, whereas endemic New Guinean species did not form clades consistent with current morphological taxonomy. Estimates of divergence using a Bayesian relaxed molecular clock model with standard mammalian nucleotide substitution rates indicated radiation of the genus in Australia in the mid to late Miocene. Persistence of Australian species of Thylogale in both southern temperate and northern tropical forests throughout the drying of the Australian continent can be attributed to their having a greater dietary flexibility than other browsing forest macropods. Divergence of the endemic New Guinean lineage occurred in the late Miocene to early Pliocene, indicating the presence of a partially forested landbridge connecting Australia and New Guinea during the Miocene. Mid-Pleistocene divergence between subspecies of the trans-Torresian T. stigmatica implies gene flow during glacial maxima between forest populations in the southern lowlands of New Guinea and the northern Cape York region of Australia. Complex structuring and relatively limited differentiation among populations of the endemic New Guinean species appears to have been influenced by the uplift of land and climate-induced redistribution of forest habitats during the late Pliocene and Pleistocene period. This is in strong contrast to the long evolutionary history and comparatively deep genetic divergence of Thylogale species in Australia. Further evaluation of the species status of the New Guinean Thylogale using more informative nuclear markers and extensive sampling is required.


Assuntos
Evolução Molecular , Macropodidae/genética , Filogenia , Animais , Austrália , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Funções Verossimilhança , Macropodidae/classificação , Modelos Genéticos , Nova Guiné , Alinhamento de Sequência , Análise de Sequência de DNA
12.
Mol Ecol ; 18(15): 3291-306, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19573029

RESUMO

Despite only limited Pleistocene glacial activity in the southern hemisphere, temperate forest species experienced complex distributional changes resulting from the combined effects of glaciation, sea level change and increased aridity. The effects of these historical processes on population genetic structure are now overlain by the effects of contemporary habitat modification. In this study, 10 microsatellites and 629 bp of the mitochondrial control region were used to assess the effects of historical forest fragmentation and recent anthropogenic habitat change on the broad-scale population genetic structuring of a southern temperate marsupial, the Tasmanian pademelon. A total of 200 individuals were sampled from seven sites across Tasmania and two islands in Bass Strait. High mitochondrial and nuclear genetic diversity indicated the maintenance of large historical population sizes. There was weak phylogeographical structuring of haplotypes, although all King Island haplotypes and three Tasmanian haplotypes formed a divergent clade implying the mid-Pleistocene isolation of a far northwestern population. Both the mitochondrial and nuclear data indicated a division of Tasmanian populations into eastern and western regions. This was consistent with a historical barrier resulting from increased aridity in the lowland 'midlands' region during glacial periods, and with a contemporary barrier resulting from recent habitat modification in that region. In Tasmania, gene flow appears to have been relatively unrestricted during glacial maxima in the west, while in the east there was evidence for historical expansion from at least one large glacial refuge and recolonization of Flinders Island.


Assuntos
Ecossistema , Evolução Molecular , Variação Genética , Genética Populacional , Marsupiais/genética , Animais , DNA Mitocondrial/genética , Fluxo Gênico , Haplótipos , Repetições de Microssatélites , Dinâmica Populacional , Análise de Sequência de DNA , Tasmânia , Árvores
13.
Parasit Vectors ; 11(1): 8, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29307305

RESUMO

BACKGROUND: Spillover of parasites at the domestic animal - wildlife interface is a pervasive threat to animal health. Cat and dog fleas (Ctenocephalides felis and C. canis) are among the world's most invasive and economically important ectoparasites. Although both species are presumed to infest a diversity of host species across the globe, knowledge on their distributions in wildlife is poor. We built a global dataset of wild mammal host associations for cat and dog fleas, and used Bayesian hierarchical models to identify traits that predict wildlife infestation probability. We complemented this by calculating functional-phylogenetic host specificity to assess whether fleas are restricted to hosts with similar evolutionary histories, diet or habitat niches. RESULTS: Over 130 wildlife species have been found to harbour cat fleas, representing nearly 20% of all mammal species sampled for fleas. Phylogenetic models indicate cat fleas are capable of infesting a broad diversity of wild mammal species through ecological fitting. Those that use anthropogenic habitats are at highest risk. Dog fleas, by contrast, have been recorded in 31 mammal species that are primarily restricted to certain phylogenetic clades, including canids, felids and murids. Both flea species are commonly reported infesting mammals that are feral (free-roaming cats and dogs) or introduced (red foxes, black rats and brown rats), suggesting the breakdown of barriers between wildlife and invasive reservoir species will increase spillover at the domestic animal - wildlife interface. CONCLUSIONS: Our empirical evidence shows that cat fleas are incredibly host-generalist, likely exhibiting a host range that is among the broadest of all ectoparasites. Reducing wild species' contact rates with domestic animals across natural and anthropogenic habitats, together with mitigating impacts of invasive reservoir hosts, will be crucial for reducing invasive flea infestations in wild mammals.


Assuntos
Animais Domésticos , Animais Selvagens , Ctenocephalides/classificação , Ctenocephalides/crescimento & desenvolvimento , Transmissão de Doença Infecciosa , Ectoparasitoses/veterinária , Animais , Canidae , Ctenocephalides/genética , Ectoparasitoses/transmissão , Felidae , Muridae , Filogenia
14.
Infect Genet Evol ; 58: 50-55, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29253672

RESUMO

Tracing the temporal dynamics of pathogens is crucial for developing strategies to detect and limit disease emergence. Canine parvovirus (CPV-2) is an enteric virus causing morbidity and mortality in dogs around the globe. Previous work in Australia reported that the majority of cases were associated with the CPV-2a subtype, an unexpected finding since CPV-2a was rapidly replaced by another subtype (CPV-2b) in many countries. Using a nine-year dataset of CPV-2 infections from 396 dogs sampled across Australia, we assessed the population dynamics and molecular epidemiology of circulating CPV-2 subtypes. Bayesian phylogenetic Skygrid models and logistic regressions were used to trace the temporal dynamics of CPV-2 infections in dogs sampled from 2007 to 2016. Phylogenetic models indicated that CPV-2a likely emerged in Australia between 1973 and 1988, while CPV-2b likely emerged between 1985 and 1998. Sequences from both subtypes were found in dogs across continental Australia and Tasmania, with no apparent effect of climate variability on subtype occurrence. Both variant subtypes exhibited a classical disease emergence pattern of relatively high rates of evolution during early emergence followed by subsequent decreases in evolutionary rates over time. However, the CPV-2b subtype maintained higher mutation rates than CPV-2a and continued to expand, resulting in an increase in the probability that dogs will carry this subtype over time. Ongoing monitoring programs that provide molecular epidemiology surveillance will be necessary to detect emergence of new variants and make informed recommendations to develop reliable detection and vaccine methods.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Genótipo , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Animais , Austrália/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , DNA Viral , Cães , Geografia , Epidemiologia Molecular , Filogenia , Vigilância em Saúde Pública , Análise de Sequência de DNA , Análise Espaço-Temporal
15.
Microb Drug Resist ; 22(7): 531-537, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26981707

RESUMO

Macrolides are often used to treat and control bacterial pathogens causing respiratory disease in pigs. This study analyzed the whole genome sequences of one clinical isolate of Actinobacillus pleuropneumoniae, Haemophilus parasuis, Pasteurella multocida, and Bordetella bronchiseptica, all isolated from Australian pigs to identify the mechanism underlying the elevated minimum inhibitory concentrations (MICs) for erythromycin, tilmicosin, or tulathromycin. The H. parasuis assembled genome had a nucleotide transition at position 2059 (A to G) in the six copies of the 23S rRNA gene. This mutation has previously been associated with macrolide resistance but this is the first reported mechanism associated with elevated macrolide MICs in H. parasuis. There was no known macrolide resistance mechanism identified in the other three bacterial genomes. However, strA and sul2, aminoglycoside and sulfonamide resistance genes, respectively, were detected in one contiguous sequence (contig 1) of A. pleuropneumoniae assembled genome. This contig was identical to plasmids previously identified in Pasteurellaceae. This study has provided one possible explanation of elevated MICs to macrolides in H. parasuis. Further studies are necessary to clarify the mechanism causing the unexplained macrolide resistance in other Australian pig respiratory pathogens including the role of efflux systems, which were detected in all analyzed genomes.


Assuntos
Actinobacillus pleuropneumoniae/genética , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Genoma Bacteriano , Infecções por Bactérias Gram-Negativas/veterinária , Infecções Respiratórias/veterinária , Doenças dos Suínos/epidemiologia , Actinobacillus pleuropneumoniae/efeitos dos fármacos , Actinobacillus pleuropneumoniae/isolamento & purificação , Animais , Antibacterianos/farmacologia , Austrália/epidemiologia , Sequência de Bases , Bordetella bronchiseptica/efeitos dos fármacos , Bordetella bronchiseptica/genética , Bordetella bronchiseptica/isolamento & purificação , Dosagem de Genes , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Haemophilus parasuis/efeitos dos fármacos , Haemophilus parasuis/genética , Haemophilus parasuis/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Pasteurella multocida/efeitos dos fármacos , Pasteurella multocida/genética , Pasteurella multocida/isolamento & purificação , RNA Ribossômico 23S/genética , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Suínos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/microbiologia
16.
PLoS One ; 10(5): e0128160, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26024370

RESUMO

Phylogeographic studies around the world have identified refugia where fauna were able to persist during unsuitable climatic periods, particularly during times of glaciation. In Australia the effects of Pleistocene climate oscillations on rainforest taxa have been well studied but less is known about the effects on mesic-habitat fauna, such as the eastern grey kangaroo (Macropus giganteus). The eastern grey kangaroo is a large mammal that is common and widespread throughout eastern Australia, preferring dry mesic habitat, rather than rainforest. As pollen evidence suggests that the central-eastern part of Australia (southeast Queensland and northern New South Wales) experienced cycles of expansion in mesic habitat with contraction in rainforests, and vice versa during glacial and interglacial periods, respectively, we hypothesise that the distribution of the eastern grey kangaroo was affected by these climate oscillations and may have contracted to mesic habitat refugia. From 375 mitochondrial DNA control region sequences from across the distribution of eastern grey kangaroos we obtained 108 unique haplotypes. Phylogenetic analysis identified two clades in Queensland, one of which is newly identified and restricted to a small coastal region in southern Queensland north of Brisbane, known as the Sunshine Coast. The relatively limited geographic range of this genetically isolated clade suggests the possibility of a mesic habitat refugium forming during rainforest expansion during wetter climate cycles. Other potential, although less likely, reasons for the genetic isolation of the highly distinct clade include geographic barriers, separate northward expansions, and strong local adaptation.


Assuntos
Macropodidae/fisiologia , Filogenia , Adaptação Fisiológica/genética , Animais , Teorema de Bayes , DNA Mitocondrial , Variação Genética , Genética Populacional , Haplótipos , Macropodidae/genética , Dados de Sequência Molecular , New South Wales , Filogeografia , Queensland , Refúgio de Vida Selvagem
17.
Mol Ecol Resour ; 14(4): 857-70, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24373173

RESUMO

For wildlife populations, it is often difficult to determine biological parameters that indicate breeding patterns and population mixing, but knowledge of these parameters is essential for effective management. A pedigree encodes the relationship between individuals and can provide insight into the dynamics of a population over its recent history. Here, we present a method for the reconstruction of pedigrees for wild populations of animals that live long enough to breed multiple times over their lifetime and that have complex or unknown generational structures. Reconstruction was based on microsatellite genotype data along with ancillary biological information: sex and observed body size class as an indicator of relative age of individuals within the population. Using body size-class data to infer relative age has not been considered previously in wildlife genealogy and provides a marked improvement in accuracy of pedigree reconstruction. Body size-class data are particularly useful for wild populations because it is much easier to collect noninvasively than absolute age data. This new pedigree reconstruction system, PR-genie, performs reconstruction using maximum likelihood with optimization driven by the cross-entropy method. We demonstrated pedigree reconstruction performance on simulated populations (comparing reconstructed pedigrees to known true pedigrees) over a wide range of population parameters and under assortative and intergenerational mating schema. Reconstruction accuracy increased with the presence of size-class data and as the amount and quality of genetic data increased. We provide recommendations as to the amount and quality of data necessary to provide insight into detailed familial relationships in a wildlife population using this pedigree reconstruction technique.


Assuntos
Marcadores Genéticos , Linhagem , Software , Animais , Animais Selvagens , Tamanho Corporal
18.
Vet J ; 201(2): 181-3, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24703323

RESUMO

Veterinarians have few tools to predict the rate of disease progression in FIV-infected cats. In contrast, in HIV infection, plasma viral RNA load and acute phase protein concentrations are commonly used as predictors of disease progression. This study evaluated these predictors in cats naturally infected with FIV. In older cats (>5 years), log10 FIV RNA load was higher in the terminal stages of disease compared to the asymptomatic stage. There was a significant association between log10 FIV RNA load and both log10 serum amyloid A concentration and age in unwell FIV-infected cats. This study suggests that viral RNA load and serum amyloid A warrant further investigation as predictors of disease status and prognosis in FIV-infected cats.


Assuntos
Proteínas de Fase Aguda/metabolismo , Progressão da Doença , Síndrome de Imunodeficiência Adquirida Felina/virologia , Vírus da Imunodeficiência Felina/fisiologia , Plasma/virologia , Carga Viral/veterinária , Animais , Austrália , Gatos , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/isolamento & purificação , RNA Viral/genética , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária
19.
PLoS One ; 8(6): e65239, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23755197

RESUMO

Moreton Bay, Queensland, Australia is an area of high biodiversity and conservation value and home to two sympatric sub-populations of Indo-Pacific bottlenose dolphins (Tursiops aduncus). These dolphins live in close proximity to major urban developments. Successful management requires information regarding their abundance. Here, we estimate total and effective population sizes of bottlenose dolphins in Moreton Bay using photo-identification and genetic data collected during boat-based surveys in 2008-2010. Abundance (N) was estimated using open population mark-recapture models based on sighting histories of distinctive individuals. Effective population size (Ne ) was estimated using the linkage disequilibrium method based on nuclear genetic data at 20 microsatellite markers in skin samples, and corrected for bias caused by overlapping generations (Ne c). A total of 174 sightings of dolphin groups were recorded and 365 different individuals identified. Over the whole of Moreton Bay, a population size N of 554 ± 22.2 (SE) (95% CI: 510-598) was estimated. The southern bay sub-population was small at an estimated N = 193 ± 6.4 (SE) (95% CI: 181-207), while the North sub-population was more numerous, with 446 ± 56 (SE) (95% CI: 336-556) individuals. The small estimated effective population size of the southern sub-population (Ne c = 56, 95% CI: 33-128) raises conservation concerns. A power analysis suggested that to reliably detect small (5%) declines in size of this population would require substantial survey effort (>4 years of annual mark-recapture surveys) at the precision levels achieved here. To ensure that ecological as well as genetic diversity within this population of bottlenose dolphins is preserved, we consider that North and South sub-populations should be treated as separate management units. Systematic surveys over smaller areas holding locally-adapted sub-populations are suggested as an alternative method for increasing ability to detect abundance trends.


Assuntos
Golfinho Nariz-de-Garrafa/fisiologia , Conservação dos Recursos Naturais , Reprodução/fisiologia , Animais , Austrália , Baías , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Repetições de Microssatélites , Densidade Demográfica
20.
Sci Rep ; 3: 2893, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-24113121

RESUMO

In this study, we conduct an in-depth analysis of annexin proteins from a diverse range of invertebrate taxa, including the major groups that contain the parasites and vector organisms that are harmful to humans and domestic animals. Using structure-based amino acid sequence alignments and phylogenetic analyses, we present a classification for this protein group and assign names to sequences with ambiguous annotations in public databases. Our analyses reveal six distinct annexin clades, and the mapping of genes encoding annexins to the genome of the human blood fluke Schistosoma mansoni supports the hypothesis of gene duplication as a major evolutionary event in annexin genesis. This study illuminates annexin diversity from a novel perspective using contemporary phylogenetic hypotheses of eukaryote evolution, and will aid the consolidation of annexin protein identities in public databases and provide a foundation for future functional analysis and characterisation of these proteins in parasites of socioeconomic importance.


Assuntos
Anexinas/genética , Estudo de Associação Genômica Ampla , Animais , Anexinas/química , Mapeamento Cromossômico , Bases de Dados Genéticas , Evolução Molecular , Humanos , Invertebrados/classificação , Invertebrados/genética , Filogenia
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