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1.
J R Soc Interface ; 18(183): 20210551, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34637641

RESUMO

Ecological and epidemiological processes and interactions influence each other, positively and negatively, directly and indirectly. The invasion potential of pathogens is influenced by the ecosystem context of their host species' populations. This extends to the capacity of (multiple) host species to maintain their (common) pathogen and the way pathogen dynamics are influenced by changes in ecosystem composition. This paper exemplifies these interactions and consequences in a study of red and grey squirrel dynamics in the UK. Differences and changes in background habitat and trophic levels above and below the squirrel species lead to different dynamic behaviour in many subtle ways. The range of outcomes of the different interactions shows that one has to be careful when drawing conclusions about the mechanisms and processes involved in explaining observed phenomena concerning pathogens in their natural environment. The dynamic behaviour also shows that planning interventions, for example for conservation purposes, benefits from understanding the complexity of interactions beyond the particular pathogen and its threatened host species.


Assuntos
Ecossistema , Mustelidae , Animais , Meio Ambiente , Sciuridae , Árvores
2.
PLoS One ; 16(9): e0242586, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34478443

RESUMO

Road ecology has traditionally focused on the impact of in-situ and functional roads on wildlife. However, road construction also poses a major, yet understudied, threat and the implications for key aspects of animal behaviour are unknown. Badgers (Meles meles) have been implicated in the transmission of tuberculosis to cattle. There are concerns that environmental disturbances, including major road construction, can disrupt badger territoriality, promoting the spread of the disease to cattle. To address these knowledge gaps the ranging behaviour of a medium-density Irish badger population was monitored using GPS-tracking collars before, during, and after a major road realignment project that bisected the study area. We estimated badgers' home range sizes, nightly distances travelled, and the distance and frequency of extra-territorial excursions during each phase of the study and quantified any changes to these parameters. We show that road construction had a very limited effect on ranging behaviour. A small increase in nightly distance during road construction did not translate into an increase in home range size, nor an increase in the distance or frequency of extra-territorial excursions during road construction. In addition, suitable mitigation measures to prevent badger deaths appeared to ensure that normal patterns of ranging behaviour continued once the new road was in place. We recommend that continuous badger-proof fencing be placed along the entire length of new major roads, in combination with appropriately sited underpasses. Our analysis supports the view that road construction did not cause badgers to change their ranging behaviour in ways likely to increase the spread of tuberculosis.


Assuntos
Mustelidae , Territorialidade , Animais , Bovinos , Reservatórios de Doenças , Mycobacterium bovis , Tuberculose Bovina
4.
J Vet Diagn Invest ; 33(6): 1079-1088, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34333997

RESUMO

Theileria parasites commonly infect African wild artiodactyls. In rare roan (Hippotragus equinus) and sable (H. niger) antelopes, Theileria sp. (sable)-associated calf mortalities constrain breeding programs. The pathogenicity of most leukocyte-transforming Theileria spp. originates in their invasion of and multiplication in various mononuclear leukocytes, the transformation of both infected and uninfected leukocytes, and their infiltration of multiple organs. Understanding the pathogenesis of theileriosis can be improved by the use of immunohistochemistry (IHC) to identify the localization of the parasites in tissue sections. Our aim was to develop a reproducible IHC assay to detect leukocyte-associated Theileria parasites in formalin-fixed, paraffin-embedded roan and sable tissues. Polyclonal antibodies were purified from the sera of 5 roans from an area endemic for Theileria sp. (sable) and tested for IHC reactivity in 55 infected and 39 control roan and sable antelopes, and for antigen and species cross-reactivity in an additional 58 cases. The 3 strongest antibodies consistently detected intraleukocytic theilerial antigens in known positive cases in roan and sable antelopes, and also detected other Theileria spp. in non-hippotraginid wild artiodactyl tissues. The antibodies did not cross-react with other apicomplexan protozoa, with the exception of Cryptosporidium. Given that PCR on its own cannot determine the significance of theilerial infection in wild ruminants, IHC is a useful laboratory test with which to confirm the diagnosis in these species.


Assuntos
Antílopes , Doenças dos Bovinos , Criptosporidiose , Cryptosporidium , Mustelidae , Parasitos , Theileria , Theileriose , Animais , Bovinos , Theileriose/diagnóstico
5.
Vet Parasitol ; 297: 109545, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34389191

RESUMO

The European badger, Meles meles (Carnivora, Mustelidae) is a widespread opportunistic omnivorous mammal. Its food spectrum comprises a wide variety of plants and small animals, occasionally including rodents, such as mice or rats. Considering that rodents are known to play a key role in the life cycle of Trichinella spp., the aims of this study were to investigate the occurrence of these parasites in badgers from Romania and to identify the species. Overall, 61 badgers originating from 14 counties were examined by trichinoscopy and artificial digestion. For species determination, the positive muscle samples, and the larvae recovered from the artificial digestion were used for DNA isolation, and further processed by multiplex PCR. A single badger, originating from Sibiu County, Central Romania, was found positive for Trichinella spp. Five cysts were identified using trichinoscopy: four in the diaphragm and one in the foreleg muscles. Artificial digestion revealed an infection rate of 70 larvae/100 g of muscle. The PCR indicated the occurrence of T. britovi, which is the most commonly detected species in wild carnivores in temperate areas. Although T. britovi has previously been reported in Romania, this represents the first report of its occurrence in the European badger in the country. However, the low prevalence indicates a minor reservoir role of this species.


Assuntos
Carnívoros , Mustelidae , Doenças dos Roedores , Trichinella , Triquinelose , Animais , Camundongos , Reação em Cadeia da Polimerase Multiplex/veterinária , Ratos , Romênia/epidemiologia , Trichinella/genética , Triquinelose/epidemiologia , Triquinelose/veterinária
6.
PLoS One ; 16(7): e0253604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197517

RESUMO

Climate change and anthropogenic modifications to the landscape can have both positive and negative effects on an animal. Linking landscape change to physiological stress and fitness of an animal is a fundamental tenet to be examined in applied ecology. Cortisol is a glucocorticoid hormone that can be used to indicate an animal's physiological stress response. In the Sierra Nevada Mountains of California, fishers (Pekania pennanti) are a threatened mesocarnivore that have been subjected to rapid landscape changes due to anthropogenic modifications and tree mortality related to a 4-year drought. We measured cortisol concentrations in the hair of 64 fishers (41 females, 23 males) captured and radio-collared in the Sierra National Forest, California. We addressed two main questions: (1) Is the physiological stress response of fishers influenced by anthropogenic factors, habitat type, canopy cover, and tree mortality due to drought in their home range? (2) Does the physiological stress response influence survival, reproduction, or body condition? We examined these factors within a fisher home range at 3 scales (30, 60, 95% isopleths). Using model selection, we found that tree mortality was the principle driver influencing stress levels among individual fishers with female and male fishers having increasing cortisol levels in home ranges with increasing tree mortality. Most importantly, we also found a link between physiological stress and demography where female fishers with low cortisol levels had the highest annual survival rate (0.94), whereas females with medium and high cortisol had lower annual survival rates, 0.78 and 0.81, respectively. We found no significant relationships between cortisol levels and body condition, male survival, or litter size. We concluded that tree mortality related to a 4-year drought has created a "landscape of stress" for this small, isolated fisher population.


Assuntos
Mudança Climática , Secas , Espécies em Perigo de Extinção/estatística & dados numéricos , Mustelidae/fisiologia , Estresse Fisiológico , Animais , California , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Feminino , Florestas , Cabelo/química , Hidrocortisona/análise , Masculino , Taxa de Sobrevida , Árvores
7.
Ecol Appl ; 31(7): e02416, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34278627

RESUMO

Rapid environmental change is reshaping ecosystems and driving species loss globally. Carnivore populations have declined and retracted rapidly and have been the target of numerous translocation projects. Success, however, is complicated when these efforts occur in novel ecosystems. Identifying refuges, locations that are resistant to environmental change, within a translocation framework should improve population recovery and persistence. American martens (Martes americana) are the most frequently translocated carnivore in North America. As elsewhere, martens were extirpated across much of the Great Lakes region by the 1930s and, despite multiple translocations beginning in the 1950s, martens remain of regional conservation concern. Surprisingly, martens were rediscovered in 2014 on the Apostle Islands of Lake Superior after a putative absence of >40 yr. To identify the source of martens to the islands and understand connectivity of the reintroduction network, we collected genetic data on martens from the archipelago and from all regional reintroduction sites. In total, we genotyped 483 individual martens, 43 of which inhabited the Apostle Islands (densities 0.42-1.46 km-2 ). Coalescent analyses supported the contemporary recolonization of the Apostle Islands with progenitors likely originating from Michigan, which were sourced from Ontario. We also identified movements by a first-order relative between the Apostle Islands and the recovery network. We detected some regional gene flow, but in an unexpected direction: individuals moving from the islands to the mainland. Our findings suggest that the Apostle Islands were naturally recolonized by progeny of translocated individuals and now act as a source back to the reintroduction sites on the mainland. We suggest that the Apostle Islands, given its protection from disturbance, complex forest structure, and reduced carnivore competition, will act as a potential refuge for marten along their trailing range boundary and a central node for regional recovery. Our work reveals that translocations, even those occurring along southern range boundaries, can create recovery networks that function like natural metapopulations. Identifying refuges, locations that are resistant to environmental change, within these recovery networks can further improve species recovery, even within novel environments. Future translocation planning should a priori identify potential refuges and sources to improve short-term recovery and long-term persistence.


Assuntos
Ecossistema , Mustelidae , Animais , Florestas , Fluxo Gênico , Genótipo , Humanos
8.
PLoS One ; 16(7): e0254387, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34288944

RESUMO

Small carnivores are of increasing conservation concern globally, including those formerly thought to be widespread and abundant. Three weasel species (Mustela nivalis, M. frenata, and M. erminea) are distributed across most of North America, yet several recent studies have reported difficulty detecting weasels within their historical range and several states have revised the status of weasels to that of species of conservation concern. To investigate the status and trends of weasels across the United States (US) and Canada, we analyzed four separate datasets: historical harvests, museum collections, citizen scientist observations (iNaturalist), and a recent US-wide trail camera survey. We observed 87-94% declines in weasel harvest across North America over the past 60 years. Declining trapper numbers and shifts in trapping practices likely partially explain the decline in harvest. Nonetheless, after accounting for trapper effort and pelt price, we still detected a significant decline in weasel harvest for 15 of 22 evaluated states and provinces. Comparisons of recent and historical museum and observational records suggest relatively consistent distributions for M. erminea, but a current range gap of >1000 km between two distinct populations of M. nivalis. We observed a dramatic drop-off in M. frenata records since 2000 in portions of its central, Great Lakes, and southern distribution, despite extensive sampling effort. In 2019, systematic trail camera surveys at 1509 sites in 50 US states detected weasels at 14 sites, all of which were above 40o latitude. While none of these datasets are individually conclusive, they collectively support the hypothesis that weasel populations have declined in North America and highlight the need for improved methods for detecting and monitoring weasels. By identifying population declines for small carnivores that were formerly abundant across North America, our findings echo recent calls to expand investigations into the conservation need of small carnivores globally.


Assuntos
Mustelidae/fisiologia , Animais , Canadá , Dinâmica Populacional , Estados Unidos
9.
EMBO Rep ; 22(9): e53619, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34322986

RESUMO

Mycobacterium tuberculosis is a fascinating object of study: it is one of the deadliest pathogens of humankind, able to fend off persistent attacks by the immune system or drugs.


Assuntos
Mel , Mustelidae , Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Animais , Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia
10.
Res Vet Sci ; 138: 196-200, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34171543

RESUMO

We report an outbreak of canine distemper virus (CDV) among stone martens (Martes foina) in Italy. After being rescued in Northern Italy between April and June 2018, six subjects were kept in a wildlife and exotic animal rescue center in Bologna province. Subjects have been monitored for 15 months in captivity. Within this time-lapse, two subjects died, while among the remaining four, only one showed clinical symptoms referable to distemper. Surviving subjects have been regularly tested for CDV by means of reverse transcriptase-PCR from conjunctival and oropharyngeal swabs for eleven months. The identified viruses belonged to the Wildlife-Europe CDV genetic subgroup. Neutralizing antibodies were detected at the end of the eleven months, when all subjects tested reverse transcriptase-PCR negative. Our findings confirm the circulation of the Wildlife-Europe CDV genetic subgroup (Europe 1/South America 1 lineage) within the Italian wildlife, and improve knowledge on viral infection in stone martens.


Assuntos
Anticorpos Antivirais/sangue , Surtos de Doenças/veterinária , Vírus da Cinomose Canina/imunologia , Cinomose/epidemiologia , Mustelidae , Animais , Anticorpos Neutralizantes/sangue , Cinomose/imunologia , Cinomose/virologia , Feminino , Itália/epidemiologia , Masculino
11.
Biol Lett ; 17(6): 20210128, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34186003

RESUMO

Are instrumented animals representative of the population, given the potential bias caused by selective sampling and the influence of capture, handling and wearing bio-loggers? The answer is elusive owing to the challenges of obtaining comparable data from individuals with and without bio-loggers. Using non-invasive genetic data of a large carnivore, the wolverine (Gulo gulo) in Scandinavia, and an open-population spatial capture-recapture model, we found a 16 (credible interval: 4-30) percentage points lower mortality probability for GPS-collared individuals compared with individuals without GPS collars. While the risk of dying from legal culling was comparable for collared and non-collared wolverines, the former experienced lower probability of mortality due to causes other than legal culling. The aforementioned effect was pronounced despite a potentially lower age-and therefore likely higher natural mortality-of collared individuals. Reports of positive effects of bio-loggers on the survival of individuals are uncommon and we argue that GPS collars could shield animals from poaching. Our results highlight the challenges of drawing population-level inferences for populations subjected to poaching when using data from instrumented individuals.


Assuntos
Mustelidae , Animais
12.
Res Vet Sci ; 138: 49-52, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34098415

RESUMO

As part of a bovine tuberculosis (bTB) control related Test and Vaccinate or Remove (TVR) badger research study in Northern Ireland, a project was launched evaluating whether badgers cross major roads (in this case the A1 dual carriageway linking Belfast/Newry/Dublin). This road formed the western boundary of the TVR study area and it was chosen to discourage badger movements in and out of the area. This was important in order to ensure that the badger study population was as stable as possible and also to get a better understanding of the risk of any spill over of bTB infection from the study area to the buffer area. Five badgers trapped close to the A1 were fitted with a Global Positioning System (GPS) collar in October 2017, which were set to record the badger location every 20 min between 19.20 and 03.00 h during a maximum of 84 days. Based on 4313 location points recorded, only 2 (0.05%) location points were located on the western side of the A1. Although this was a small sample, it can be concluded that generally badgers avoid crossing dual carriageways which is supported by evidence from other studies. This finding is important for informing on development of future badger intervention areas where major roads could be considered as strong borders. Furthermore, it adds to the body of knowledge in trying to understand drivers and barriers for badger dispersal behaviour.


Assuntos
Distribuição Animal , Mustelidae/fisiologia , Tuberculose Bovina/prevenção & controle , Animais , Bovinos , Feminino , Masculino , Movimento , Irlanda do Norte
13.
Biomolecules ; 11(5)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064759

RESUMO

Gammaherpesvirus reactivation can promote diseases or impair reproduction. Understanding reactivation patterns and associated risks of different stressors is therefore important. Nevertheless, outside the laboratory or captive environment, studies on the effects of stress on gammaherpesvirus reactivation in wild mammals are lacking. Here we used Mustelid gammaherpesvirus 1 (MusGHV-1) infection in European badgers (Meles meles) as a host-pathogen wildlife model to study the effects of a variety of demographic, physiological and environmental stressors on virus shedding in the genital tract. We collected 251 genital swabs from 150 free-ranging individuals across three seasons and screened them for the presence of MusGHV-1 DNA using PCR targeting the DNA polymerase gene. We explored possible links between MusGHV-1 DNA presence and seven variables reflecting stressors, using logistic regression analysis. The results reveal different sets of risk factors between juveniles and adults, likely reflecting primary infection and reactivation. In adults, virus shedding was more likely in badgers in poorer body condition and younger than 5 years or older than 7; while in juveniles, virus shedding is more likely in females and individuals in better body condition. However, living in social groups with more cubs was a risk factor for all badgers. We discuss possible explanations for these risk factors and their links to stress in badgers.


Assuntos
Gammaherpesvirinae/isolamento & purificação , Infecções por Herpesviridae/veterinária , Mustelidae/virologia , Animais , Feminino , Genitália/virologia , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/virologia , Masculino , Reprodução/fisiologia , Fatores de Risco , Estações do Ano , Estresse Fisiológico/fisiologia , Ativação Viral
14.
PLoS Comput Biol ; 17(6): e1009005, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34170901

RESUMO

Multi-host pathogens are particularly difficult to control, especially when at least one of the hosts acts as a hidden reservoir. Deep sequencing of densely sampled pathogens has the potential to transform this understanding, but requires analytical approaches that jointly consider epidemiological and genetic data to best address this problem. While there has been considerable success in analyses of single species systems, the hidden reservoir problem is relatively under-studied. A well-known exemplar of this problem is bovine Tuberculosis, a disease found in British and Irish cattle caused by Mycobacterium bovis, where the Eurasian badger has long been believed to act as a reservoir but remains of poorly quantified importance except in very specific locations. As a result, the effort that should be directed at controlling disease in badgers is unclear. Here, we analyse densely collected epidemiological and genetic data from a cattle population but do not explicitly consider any data from badgers. We use a simulation modelling approach to show that, in our system, a model that exploits available cattle demographic and herd-to-herd movement data, but only considers the ability of a hidden reservoir to generate pathogen diversity, can be used to choose between different epidemiological scenarios. In our analysis, a model where the reservoir does not generate any diversity but contributes to new infections at a local farm scale are significantly preferred over models which generate diversity and/or spread disease at broader spatial scales. While we cannot directly attribute the role of the reservoir to badgers based on this analysis alone, the result supports the hypothesis that under current cattle control regimes, infected cattle alone cannot sustain M. bovis circulation. Given the observed close phylogenetic relationship for the bacteria taken from cattle and badgers sampled near to each other, the most parsimonious hypothesis is that the reservoir is the infected badger population. More broadly, our approach demonstrates that carefully constructed bespoke models can exploit the combination of genetic and epidemiological data to overcome issues of extreme data bias, and uncover important general characteristics of transmission in multi-host pathogen systems.


Assuntos
Simulação por Computador , Reservatórios de Doenças , Mycobacterium bovis/isolamento & purificação , Filogenia , Tuberculose Bovina/transmissão , Animais , Bovinos , Mustelidae/microbiologia , Mycobacterium bovis/classificação , Mycobacterium bovis/genética , Tuberculose Bovina/microbiologia
15.
BMC Ecol Evol ; 21(1): 82, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975536

RESUMO

BACKGROUND: Population size and densities are key parameters in both fundamental and applied ecology, as they affect population resilience to density-dependent processes, habitat changes and stochastic events. Efficient management measures or species conservation programs thus require accurate estimates of local population densities across time and space, especially for continuously distributed species. For social species living in groups, population density depends on different components, namely the number of groups and the group size, for which relative variations in space may originate from different environmental factors. Whether resulting spatial variations in density are mostly triggered by one component or the other remains poorly known. Here, we aimed at determining the magnitude of the spatial variation in population densities of a social, group-living species, i.e. the European badger Meles meles, in 13 different sites of around 50 km2 across France, to decipher whether sett density, group size or proportion of occupied sett variation is the main factor explaining density variation. Besides the intrinsic factors of density variation, we also assessed whether habitat characteristics such as habitat fragmentation, urbanisation, and resource availability, drove both the spatial variation of density components and local population densities. RESULTS: We proposed a new standardised approach combining use of multiple methods, namely distance sampling for estimating the density of occupied sett clusters, i.e. group density, and camera and hair trapping for genetic identification to determine the mean social group size. The density of adult badgers was on average 3.8 per km2 (range 1.7-7.9 per km2) and was positively correlated with the density of sett clusters. The density of adult badgers per site was less related to the social group size or to the proportion of occupied sett clusters. Landscape fragmentation also explained the spatial variation of adult badger density, with highly fragmented landscapes supporting lower adult densities. Density components were linked differently to environmental variables. CONCLUSIONS: These results underline the need to break down population density estimates into several components in group-living species to better understand the pattern of temporal and spatial variation in population density, as different components may vary due to different ecological factors.


Assuntos
Mustelidae , Animais , Ecossistema , França , Densidade Demográfica
16.
Epidemiol Infect ; 149: e125, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33958017

RESUMO

The role of the Eurasian badger (Meles meles) as a wildlife host has complicated the management of bovine tuberculosis (bTB) in cattle. Badger ranging behaviour has previously been found to be altered by culling of badgers and has been suggested to increase the transmission of bTB either among badgers or between badgers and cattle. In 2014, a five-year bTB intervention research project in a 100 km2 area in Northern Ireland was initiated involving selective removal of dual path platform (DPP) VetTB (immunoassay) test positive badgers and vaccination followed by release of DPP test negative badgers ('Test and Vaccinate or Remove'). Home range sizes, based on position data obtained from global positioning system collared badgers, were compared between the first year of the project, where no DPP test positive badgers were removed, and follow-up years 2-4 when DPP test positive badgers were removed. A total of 105 individual badgers were followed over 21 200 collar tracking nights. Using multivariable analyses, neither annual nor monthly home ranges differed significantly in size between years, suggesting they were not significantly altered by the bTB intervention that was applied in the study area.


Assuntos
Comportamento de Retorno ao Território Vital , Mustelidae/fisiologia , Tuberculose Bovina/prevenção & controle , Abate de Animais , Animais , Bovinos , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/veterinária , Feminino , Masculino , Mustelidae/microbiologia , Mycobacterium bovis/imunologia , Mycobacterium bovis/isolamento & purificação , Irlanda do Norte/epidemiologia , Tuberculose Bovina/diagnóstico , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/transmissão , Vacinação/veterinária
17.
J Wildl Dis ; 57(3): 601-611, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33979445

RESUMO

Marine birds are frequently found dead on beaches, either from natural or from anthropogenic causes. Complete necropsies of those carcasses can provide valuable information, particularly for pelagic species, such as Northern Fulmars (Fulmarus glacialis) and shearwaters, which come to land only to breed and for which information on diseases that may affect them is, therefore, sparse. Between 2000 and 2012, 315 carcasses of four species of Procellariiformes (173 Northern Fulmars, 89 Great Shearwaters [Ardenna gravis], 50 Sooty Shearwaters [Ardenna grisea], and three Cory's Shearwaters [Calonectris diomedea]) were collected on Sable Island, Nova Scotia, Canada, an isolated island near the edge of the continental shelf. A complete necropsy, including examination for the presence of ingested plastic, was performed on all carcasses. Most (70%) of these birds were immature. The cause of death was undetermined in 22% (n=70) of the birds: 36% (62/173) of the Northern Fulmars, 4% (4/89) of the Great Shearwaters, 6% (3/50) of the Sooty Shearwaters, and 33% (1/3) of the Cory's Shearwaters. Emaciation was considered the primary cause of death in 91% of the remaining 245 birds: 87% (97/111) of the Northern Fulmars, 92% (78/85) of the Great Shearwaters, 100% (47/47) of the Sooty Shearwaters, and 100% (2/2) of the Cory's Shearwaters. Notable primary causes of death other than emaciation included mycobacteriosis and neoplasia in Northern Fulmars and transmural parasitic proventriculitis in Great Shearwaters. For Northern Fulmars, nutritional condition (as determined semiquantitatively) was compared with other parameters. Birds in good nutritional condition had heavier body mass and flight muscle mass than those in poor nutritional condition (P<0.01). More adults were in poor nutritional condition than expected by chance (91%; χ2=8.23, P<0.01), whereas only 57% of immature birds were in poor condition. There was no relationship between nutritional condition and sex or mass of ingested plastic. Our study provides information on some previously unsuspected health threats in Procellariiformes.


Assuntos
Conteúdo Gastrointestinal , Mustelidae , Animais , Aves , Canadá , Monitoramento Ambiental , Nova Escócia/epidemiologia
18.
Parasit Vectors ; 14(1): 204, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33874985

RESUMO

BACKGROUND: Previously, twelve Rickettsia species were identified in ticks, fleas, sheep keds (Melophagus ovinus), bats (Pipistrellus pipistrellus) and a tick-bitten patient in the Xinjiang Uygur Autonomous Region (XUAR) in northwestern China. Here we aimed to molecularly detect rickettsial agents in red fox (Vulpes vulpes), marbled polecat (Vormela peregusna) and their ticks. METHODS: During 2018-2019, 12 red foxes, one marbled polecat and their ticks were sampled in two counties and a city of the XUAR. The heart, liver, spleen, lung and kidney of these 13 carnivores were dissected, followed by DNA extraction. Hard ticks were identified both morphologically and molecularly. All samples were examined for the presence of rickettsiae by amplifying four genetic markers (17-kDa, gltA, ompA, sca1). RESULTS: A total of 26 adult ticks and 28 nymphs (38 Ixodes canisuga, nine Ixodes kaiseri, six Haemaphysalis erinacei and one Dermacentor marginatus) were collected from red foxes, and four Ha. erinacei ticks were removed from the marbled polecat. Analysis of cytochrome c oxidase subunit I (COI) gene sequences indicated that 2-32 nucleotides differed between I. canisuga, I. kaiseri and Ha. erinacei from northwestern China and Europe. Rickettsia raoultii was detected in three red foxes, Candidatus Rickettsia barbariae in a red fox, Rickettsia sibirica in a red fox and a marbled polecat, and R. raoultii in two tick species (I. canisuga and D. marginatus). CONCLUSIONS: To the best of our knowledge, I. canisuga and I. kaiseri have not been previously reported from red foxes in China. The DNA of R. sibirica and R. raoultii was detected for the first time in the organs of red foxes, and R. sibirica in the organs of a marbled polecat. This is also the first molecular evidence for the presence of R. raoultii in I. canisuga. Our findings expand the range of tick-borne pathogens in wildlife species and associated ticks in China.


Assuntos
Raposas/microbiologia , Mustelidae/microbiologia , Rickettsia/isolamento & purificação , Infestações por Carrapato/veterinária , Carrapatos/microbiologia , Animais , Animais Selvagens/microbiologia , Proteínas de Bactérias/genética , China , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogenia , Rickettsia/classificação , Rickettsia/genética , Infestações por Carrapato/parasitologia , Carrapatos/classificação , Carrapatos/fisiologia
19.
Environ Monit Assess ; 193(5): 257, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837466

RESUMO

Due to ubiquitous distribution of taxa, relatively low-cost and efficient sampling procedure, and known responses to environmental gradients, macroinvertebrate indicators are often a central component of biological monitoring of freshwater resources. This study examined establishing a baseline reference of benthic macroinvertebrate indicators in a biomonitoring approach as a means for monitoring the freshwater ponds of Sable Island National Park Reserve (SINPR), Canada. We compared water quality parameters monitored from 2015 to 2019 to a biomonitoring approach deployed in May, June, and August of 2019. A total of 27 taxa were recorded from the 30,226 specimens collected, with highest abundances of Corixidae, Amphipoda, Oligochaeta, and chironomid species Polypedilum bicrenatum. We found significant variability of community structure between different months of sampling (p = 0.001) and between ponds (p < 0.0001). A high correlation was found between dissolved organic carbon, sulfate, and the diversity of macroinvertebrate indicators, while conductivity, ammonia, and calcium were found to be correlated with species richness. While we found that water chemistry parameters exhibited spatial and temporal differences, the diversity of macroinvertebrate indicators is likely to be a more resilient metric for comparison between ponds. Further, our findings demonstrate that biomonitoring can be effective in systems with a low number of small, shallow, freshwater pond ecosystems. As our study deployed a high-resolution identification of biological indicators, we were able to establish a baseline reference for future monitoring as well as identify specific associations between pond water quality and biological assemblages that can be used as a context for the management of SINPR's freshwater resources. Continued monitoring of these ecosystems in future years will help to understand long-term environmental changes on the island.


Assuntos
Ecossistema , Mustelidae , Animais , Canadá , Monitoramento Ambiental , Água Doce , Invertebrados , Ilhas , Parques Recreativos , Rios
20.
Ticks Tick Borne Dis ; 12(4): 101710, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827036

RESUMO

Babesia species (Apicomplexa: Piroplasmorida) are tick-borne protozoan hemoparasites, which pose a significant threat to domestic animals, wildlife and humans. This study aimed to determine and characterize Babesia species in red foxes (Vulpes vulpes), Asian badgers (Meles leucurus) and their ticks. Blood, heart, liver, spleen, lung, kidney, large intestine and small intestine were collected from 19 wild carnivores (12 red foxes and 7 Asian badgers). All ticks were removed from these animals and identified according to morphological and molecular characteristics. The samples were tested for the presence of Babesia species using the 18S rRNA gene. Molecular analyses showed that the DNA of Babesia vogeli and Babesia vulpes was present in red fox organs/tissues and blood samples. A total of 54 hard ticks (38 Ixodes canisuga, 6 Haemaphysalis erinacei, 9 Ixodes kaiseri and 1 Dermacentor marginatus) were collected from red foxes and 12 (I. kaiseri) from Asian badgers. All ticks were adults. Among them, one I. kaiseri parasiting a red fox contained the DNA of B. vulpes while one I. canisuga was positive for Babesia sp. belonging to the clade "Babesia sensu stricto". Molecular and phylogenetic analyses indicated the presence of a novel genotype, Babesia sp. "badger China". Babesia sp. badger type A and type B from Asian badgers were different from those in European badgers. Co-infection with three Babesia genotypes was found in one Asian badger. This study provides the first data on Babesia infection in red foxes, Asian badgers and their ticks in China. Babesia vogeli was detected for the first time in red foxes in Asia. Co-infection and genetic diversity of Babesia genotypes in Asian badgers were also demonstrated.


Assuntos
Babesia/isolamento & purificação , Babesiose/epidemiologia , Raposas , Ixodidae/parasitologia , Mustelidae , Animais , Babesia/classificação , Babesiose/parasitologia , China/epidemiologia , Filogenia , Prevalência , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
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