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1.
J Zoo Wildl Med ; 55(1): 31-41, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38453485

RESUMO

Between 2015 and 2019, a health screening was carried out annually on captive-bred Partula snails prior to export for reintroduction as part of an international effort to repopulate areas of French Polynesia, where the snails were extinct or critically endangered. In total, 129 separate tank populations of 12 different species were screened at ZSL London Zoo. Wet mounts and smears stained with modified Ziehl-Neelsen (MZN) of 535 fecal samples were examined, and 45% contained flagellated protozoa, and 35.5% had MZN-positive oocysts, measuring 3-5 µm in diameter. Smaller (2 µm) presumptive spores, MZN-positive bacilli, ciliated protozoa and nematodes were recorded less frequently. Fecal bacterial culture yielded mixed species, with a clear predominance of Myroides species (88.9% of samples). The MZN-positive oocysts (3-5 µm) were present in 6.5% of impression smears from the apices of 432 snails examined postmortem, plus acid-fast bacilli in a few cases, but no 2 µm spores. Mixed bacteria were cultured from coelomic swabs, with Myroides species again the most common (63.5%). Histologic examination was carried out on 292 snails. Autolysis affected almost 90% of those found dead but only 3.4% of euthanized snails. Histology commonly identified microsporidial sporocysts in the digestive gland and midgut epithelium of all but two species. Intracellular, extracytoplasmic Cryptosporidium-like organisms were also common in the midgut but were only observed when snails were fixed in 10% formalin (2017-2019), not ethanol. There were no clear pathologic changes associated with either organism. Pigmented hemocytic nodules were commonly observed, most frequently in the foot process; these were either age related or evidence of prior chronic inflammatory reaction and of low clinical significance. With no evidence of poor health and no significant organisms found, a total of 4,978 individuals representing 12 species were exported for reintroduction.


Assuntos
Criptosporidiose , Cryptosporidium , Microsporídios , Animais , Criptosporidiose/parasitologia , Bactérias , Fezes/parasitologia
2.
Transbound Emerg Dis ; 69(6): 3684-3692, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36217722

RESUMO

Usutu virus (USUV) is an emerging zoonotic arbovirus in Europe, where it primarily impacts Eurasian blackbirds (Turdus merula). For mosquito-borne viruses to persist in temperate areas, transovarial transmission in vectors or overwintering in either hosts or diapausing vectors must occur to facilitate autochthonous transmission. We undertook surveillance of hosts and vectors in 2021 to elucidate whether USUV had overwintered in the United Kingdom (UK) following its initial detection there in 2020. From 175 dead bird submissions, we detected 1 case of USUV infection, in a blackbird, from which a full USUV genome was derived. Using a molecular clock analysis, we demonstrate that the 2021 detection shared a most recent common ancestor with the 2020 Greater London, UK, USUV sequence. In addition, we identified USUV-specific neutralizing antibodies in 10 out of 86 serum samples taken from captive birds at the index site, demonstrating in situ cryptic infection and potential sustained transmission. However, from 4966 mosquitoes, we detected no USUV RNA suggesting that prevalence in the vector community was absent or low during sampling. Combined, these results suggest that USUV overwintered in the UK, thus providing empirical evidence for the continued northward expansion of this vector-borne viral disease. Currently, our detection indicates geographically restricted virus persistence. Further detections over time will be required to demonstrate long-term establishment. It remains unclear whether the UK, and by extension other high-latitude regions, can support endemic USUV infection.


Assuntos
Doenças das Aves , Infecções por Flavivirus , Flavivirus , Aves Canoras , Animais , Mosquitos Vetores , Flavivirus/genética , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/veterinária , Reino Unido/epidemiologia
3.
Sci Rep ; 12(1): 10298, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35717348

RESUMO

Following the first detection in the United Kingdom of Usutu virus (USUV) in wild birds in 2020, we undertook a multidisciplinary investigation that combined screening host and vector populations with interrogation of national citizen science monitoring datasets to assess the potential for population impacts on avian hosts. Pathological findings from six USUV-positive wild passerines were non-specific, highlighting the need for molecular and immunohistochemical examinations to confirm infection. Mosquito surveillance at the index site identified USUV RNA in Culex pipiens s.l. following the outbreak. Although the Eurasian blackbird (Turdus merula) is most frequently impacted by USUV in Europe, national syndromic surveillance failed to detect any increase in occurrence of clinical signs consistent with USUV infection in this species. Furthermore, there was no increase in recoveries of dead blackbirds marked by the national ringing scheme. However, there was regional clustering of blackbird disease incident reports centred near the index site in 2020 and a contemporaneous marked reduction in the frequency with which blackbirds were recorded in gardens in this area, consistent with a hypothesis of disease-mediated population decline. Combining results from multidisciplinary schemes, as we have done, in real-time offers a model for the detection and impact assessment of future disease emergence events.


Assuntos
Doenças das Aves , Infecções por Flavivirus , Flavivirus , Aves Canoras , Animais , Surtos de Doenças/veterinária , Flavivirus/genética , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/veterinária , Mosquitos Vetores , Reino Unido/epidemiologia
4.
Viruses ; 14(3)2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35336912

RESUMO

Bluetongue virus (BTV) and African horse sickness virus (AHSV) cause economically important diseases that are currently exotic to the United Kingdom (UK), but have significant potential for introduction and onward transmission. Given the susceptibility of animals kept in zoo collections to vector-borne diseases, a qualitative risk assessment for the introduction of BTV and AHSV to ZSL London Zoo was performed. Risk pathways for each virus were identified and assessed using published literature, animal import data and outputs from epidemiological models. Direct imports of infected animals, as well as wind-borne infected Culicoides, were considered as routes of incursion. The proximity of ongoing disease events in mainland Europe and proven capability of transmission to the UK places ZSL London Zoo at higher risk of BTV release and exposure (estimated as low to medium) than AHSV (estimated as very low to low). The recent long-range expansion of AHSV into Thailand from southern Africa highlights the need for vector competence studies of Palearctic Culicoides for AHSV to assess the risk of transmission in this region.


Assuntos
Vírus da Doença Equina Africana , Doença Equina Africana , Vírus Bluetongue , Bluetongue , Ceratopogonidae , Doença Equina Africana/epidemiologia , Animais , Bluetongue/epidemiologia , Cavalos , Medição de Risco , Ovinos , Reino Unido/epidemiologia
5.
Conserv Biol ; 35(2): 502-509, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32656858

RESUMO

Measuring progress toward international biodiversity targets requires robust information on the conservation status of species, which the International Union for Conservation of Nature (IUCN) Red List of Threatened Species provides. However, data and capacity are lacking for most hyperdiverse groups, such as invertebrates, plants, and fungi, particularly in megadiverse or high-endemism regions. Conservation policies and biodiversity strategies aimed at halting biodiversity loss by 2020 need to be adapted to tackle these information shortfalls after 2020. We devised an 8-point strategy to close existing data gaps by reviving explorative field research on the distribution, abundance, and ecology of species; linking taxonomic research more closely with conservation; improving global biodiversity databases by making the submission of spatially explicit data mandatory for scientific publications; developing a global spatial database on threats to biodiversity to facilitate IUCN Red List assessments; automating preassessments by integrating distribution data and spatial threat data; building capacity in taxonomy, ecology, and biodiversity monitoring in countries with high species richness or endemism; creating species monitoring programs for lesser-known taxa; and developing sufficient funding mechanisms to reduce reliance on voluntary efforts. Implementing these strategies in the post-2020 biodiversity framework will help to overcome the lack of capacity and data regarding the conservation status of biodiversity. This will require a collaborative effort among scientists, policy makers, and conservation practitioners.


Una Estrategia para la Siguiente Década para Enfrentar la Deficiencia de Datos de la Biodiversidad Ignorada Resumen La medida del avance hacia los objetivos internacionales para la biodiversidad requiere información sólida sobre el estado de conservación de las especies, la cual proporciona la Lista Roja de Especies Amenazadas de la Unión Internacional para la Conservación de la Naturaleza (UICN). Sin embargo, los grupos más hiperdiversos, como los invertebrados, las plantas y los hongos, carecen de datos y capacidad, particularmente en regiones megadiversas o de endemismo alto. Las políticas de conservación y las estrategias de biodiversidad dirigidas hacia el cese de la pérdida de biodiversidad para el 2020 necesitan ser adaptadas para solucionar estas insuficiencias de información para después del año 2020. Diseñamos una estrategia de ocho puntos para cerrar las brechas existentes en los datos mediante la reactivación de la investigación exploratoria en el campo sobre la distribución, abundancia y ecología de las especies; la vinculación más cercana entre la investigación taxonómica y la conservación; la mejora a las bases de datos mundiales sobre biodiversidad mediante la presentación obligatoria de datos espacialmente explícitos para las publicaciones científicas; el desarrollo de una base mundial de datos espaciales sobre las amenazas para la biodiversidad para facilitar las valoraciones de la Lista Roja de la UICN; la automatización de las preevaluaciones mediante la integración de datos de distribución y datos de amenazas espaciales; el desarrollo de la capacidad en la taxonomía, la ecología y el monitoreo de la biodiversidad en países con una gran riqueza de especies o endemismos; la creación de programas de monitoreo de especies para los taxones menos conocidos; el desarrollo de suficientes mecanismos de financiamiento para reducir la dependencia de los esfuerzos voluntarios. La implementación de estas estrategias en el marco de trabajo para la biodiversidad posterior al 2020 ayudará a superar la falta de capacidad y datos con respecto al estado de conservación de la biodiversidad. Lo anterior requerirá de un esfuerzo colaborativo entre científicos, formuladores de políticas y practicantes de la conservación.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Ecologia , Espécies em Perigo de Extinção , Plantas
6.
Parasit Vectors ; 13(1): 139, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32178710

RESUMO

BACKGROUND: Culicoides biting midges are biological vectors of arboviruses including bluetongue virus (BTV), Schmallenberg virus (SBV) and African horse sickness virus (AHSV). Zoos are home to a wide range of 'at risk' exotic and native species of animals. These animals have a high value both in monetary terms, conservation significance and breeding potential. To understand the risk these viruses pose to zoo animals, it is necessary to characterise the Culicoides fauna at zoos and determine which potential vector species are feeding on which hosts. METHODS: Light-suction traps were used at two UK zoos: the Zoological Society of London (ZSL) London Zoo (LZ) and ZSL Whipsnade Zoo (WZ). Traps were run one night each week from June 2014 to June 2015. Culicoides were morphologically identified to the species level and any blood-fed Culicoides were processed for blood-meal analysis. DNA from blood meals was extracted and amplified using previously published primers. Sequencing was then carried out to determine the host species. RESULTS: A total of 11,648 Culicoides were trapped and identified (n = 5880 from ZSL WZ; n = 5768 from ZSL LZ), constituting 25 different species. The six putative vectors of BTV, SBV and AHSV in northern Europe were found at both zoos and made up the majority of the total catch (n = 10,701). A total of 31 host sequences were obtained from blood-fed Culicoides. Culicoides obsoletus/C. scoticus, Culicoides dewulfi, Culicoides parroti and Culicoides punctatus were found to be biting a wide range of mammals including Bactrian camels, Indian rhinoceros, Asian elephants and humans, with Culicoides obsoletus/C. scoticus also biting Darwin's rhea. The bird-biting species, Culicoides achrayi, was found to be feeding on blackbirds, blue tits, magpies and carrion crows. CONCLUSIONS: To our knowledge, this is the first study to directly confirm blood-feeding of Culicoides on exotic zoo animals in the UK and shows that they are able to utilise a wide range of exotic as well as native host species. Due to the susceptibility of some zoo animals to Culicoides-borne arboviruses, this study demonstrates that in the event of an outbreak of one of these viruses in the UK, preventative and mitigating measures would need to be taken.


Assuntos
Animais de Zoológico/sangue , Ceratopogonidae/classificação , Comportamento Alimentar , Animais , Feminino , Insetos Vetores/classificação , Masculino , Análise de Sequência de DNA , Reino Unido
7.
Vet Med Int ; 2017: 6585380, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28638674

RESUMO

Studying personality in captive animals may enable the development of individual-based management decisions, which may improve animal welfare. Asiatic lions at London Zoo represent an opportunity to research an understudied species' response to new environments since they have experienced social and physical changes, such as new enclosures and increased social interaction with humans. This project aimed to investigate the role of personality in behavioral responses to these changes. Lion personality questionnaires completed by keepers and direct focal animal observations were used to create personality profiles. Time budgets and enclosure use were determined and compared between control nights and event nights and between the lions' previous enclosure and their new one. The results showed a lack of difference in time budget and enclosure use between control and social event nights, and the spread of participation index values revealed that the lions use their enclosures unevenly. Personality profiles identified various traits that could assist with individual-based management decisions. As the first study to assess Asiatic lions personality, this research contributes to the creation of consistent and valid methodology for evaluating captive animal personality that may improve husbandry and welfare protocols for individual lions, leading to the improved health and success of the species.

8.
Animals (Basel) ; 7(5)2017 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-28505095

RESUMO

Three brown bear (Ursusarctosarctos) individuals and two sloth bear (Melursusursinusinornatus) individuals were observed in captivity to produce behavioural profiles for each individual. Data collected through behavioural observations were used to produce activity budgets, and to identify space usage and certain aspects of social behavior. Behaviour monitoring allowed the researchers to evaluate the welfare of the animals by identifying the occurrence of stereotypic behaviours, which are sometimes associated with stress. Behavioural profiles were created using data obtained through behavioural observations (coding) and keeper questionnaires (rating). The behavioural observations indicated a number of stereotypic behaviours in sloth bears but not in brown bears. The uniformity of zone usage was calculated to investigate if the enclosure size and features were adequate for use, and a social aspect of otherwise solitary animals was also identified. The behavioural profiles generated through coding and rating were compared to determine the reliability between these two methods in Ursids. Profiles were not compared between individuals since this study is not a comparison between different personality types but rather an effort (one of the few ones existing in literature) to select a valid and reproducible methodology capable of assessing personality in bears.

9.
Science ; 354(6313)2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-27846577

RESUMO

Most ecological processes now show responses to anthropogenic climate change. In terrestrial, freshwater, and marine ecosystems, species are changing genetically, physiologically, morphologically, and phenologically and are shifting their distributions, which affects food webs and results in new interactions. Disruptions scale from the gene to the ecosystem and have documented consequences for people, including unpredictable fisheries and crop yields, loss of genetic diversity in wild crop varieties, and increasing impacts of pests and diseases. In addition to the more easily observed changes, such as shifts in flowering phenology, we argue that many hidden dynamics, such as genetic changes, are also taking place. Understanding shifts in ecological processes can guide human adaptation strategies. In addition to reducing greenhouse gases, climate action and policy must therefore focus equally on strategies that safeguard biodiversity and ecosystems.


Assuntos
Aclimatação , Biodiversidade , Mudança Climática , Variação Genética , Animais , Produtos Agrícolas/genética , Pesqueiros , Cadeia Alimentar , Água Doce , Humanos , Dinâmica Populacional , Razão de Masculinidade
10.
PLoS One ; 8(12): e80311, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24348999

RESUMO

Given current extinction trends, the number of species requiring conservation breeding programs (CBPs) is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23%) terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful.


Assuntos
Cruzamento , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Animais , Animais de Zoológico , Feminino , Masculino
11.
BMC Evol Biol ; 9: 204, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19686604

RESUMO

BACKGROUND: The mass extirpation of the island of Moorea's endemic partulid tree snail fauna, following the deliberate introduction of the alien predator Euglandina rosea, represents one of the highest profile conservation crises of the past thirty years. All of the island's partulids were thought to be extirpated by 1987, with five species persisting in zoos, but intensive field surveys have recently detected a number of surviving wild populations. We report here a mitochondrial (mt) phylogenetic estimate of Moorean partulid wild and captive lineage survival calibrated with a reference museum collection that pre-dates the predator's introduction and that also includes a parallel dataset from the neighboring island of Tahiti. RESULTS: Although severe winnowing of Moorea's mt lineage diversity has occurred, seven of eight (six Partula; two Samoana) partulid tip clades remain extant. The extinct mt clade occurred predominantly in the P. suturalis species complex and it represented a major component of Moorea's endemic partulid treespace. Extant Moorean mt clades exhibited a complex spectrum of persistence on Moorea, in captivity, and (in the form of five phylogenetically distinct sister lineages) on Tahiti. Most notably, three Partula taxa, bearing two multi-island mt lineages, have survived decades of E. rosea predation on Moorea (P. taeniata) and in the valleys of Tahiti (P. hyalina and P. clara). Their differential persistence was correlated with intrinsic attributes, such as taxonomy and mt lineages, rather than with their respective within-island distribution patterns. CONCLUSION: Conservation efforts directed toward Moorean and Tahitian partulids have typically operated within a single island frame of reference, but our discovery of robust genealogical ties among survivors on both islands implies that a multi-island perspective is required. Understanding what genetic and/or ecological factors have enabled Partula taeniata, P. hyalina and P. clara to differentially survive long-term direct exposure to the predator may provide important clues toward developing a viable long term conservation plan for Society Island partulid tree snails.


Assuntos
Conservação dos Recursos Naturais , Extinção Biológica , Filogenia , Caramujos/genética , Animais , DNA Mitocondrial/genética , Variação Genética , Geografia , Polinésia , Análise de Sequência de DNA , Caramujos/classificação
12.
Proc Biol Sci ; 274(1627): 2907-14, 2007 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-17848368

RESUMO

Inter-archipelago exchange networks were an important aspect of prehistoric Polynesian societies. We report here a novel genetic characterization of a prehistoric exchange network involving an endemic Pacific island tree snail, Partula hyalina. It occurs in the Society (Tahiti only), Austral and Southern Cook Islands. Our genetic data, based on museum, captive and wild-caught samples, establish Tahiti as the source island. The source lineage is polymorphic in shell coloration and contains a second nominal species, the dark-shelled Partula clara, in addition to the white-shelled P. hyalina. Prehistoric inter-island introductions were non-random: they involved white-shelled snails only and were exclusively inter-archipelago in scope. Partulid shells were commonly used in regional Polynesian jewellery, and we propose that the white-shelled P. hyalina, originally restricted to Tahiti, had aesthetic value throughout these archipelagoes. Demand within the Society Islands could be best met by trading dead shells, but a low rate of inter-archipelago exchange may have prompted the establishment of multiple founder populations in the Australs and Southern Cooks. The alien carnivorous land snail Euglandina rosea has recently devastated populations of all 61 endemic species of Society Island partulid snails. Southern Cooks and Australs P. hyalina now represent the only unscathed wild populations remaining of this once spectacular land snail radiation.


Assuntos
Conservação dos Recursos Naturais , Caramujos/classificação , Animais , Comércio , DNA Mitocondrial/química , Haplótipos , Humanos , Funções Verossimilhança , Polinésia , Caramujos/genética , Comportamento Social
13.
Curr Biol ; 17(13): R502-3, 2007 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-17610827

RESUMO

Oceanic islands frequently support endemic faunal radiations that are highly vulnerable to introduced predators [1]. This vulnerability is epitomized by the rapid extinction in the wild of all but five of 61 described Society Islands partulid tree snails [2], following the deliberate introduction of an alien biological control agent: the carnivorous snail Euglandina rosea[3]. Tahiti's tree snail populations have been almost completely extirpated and three of the island's eight endemic Partula species are officially extinct, a fourth persisting only in captivity [2]. We report a molecular phylogenetic estimate of Tahitian Partula mitochondrial lineage survival calibrated with a 1970 reference museum collection that pre-dates the predator's 1974 introduction to the island [4]. Although severe winnowing of lineage diversity has occurred, none of the five primary Tahitian Partula clades present in the museum samples is extinct. Targeted conservation measures, especially of montane refuge populations, may yet preserve a representative sub-sample of Tahiti's endemic tree snail genetic diversity in the wild.


Assuntos
DNA Mitocondrial , Filogenia , Caramujos/genética , Animais , Extinção Biológica , Geografia , Polinésia
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