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1.
Parasitol Res ; 123(4): 195, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38658460

RESUMEN

Among the species described within the Onchocercidae family, Dirofilaria immitis is regarded as the most common worldwide, causing severe and often fatal conditions in dogs, cats, and occasionally humans. Dirofilaria spp. are vectored by mosquitoes, simulids, and culicoids, with their epidemiology dependent on the geographical distribution of competent vectors. Eight species of Dirofilaria have been reported so far in Brazil, of which six parasitize non-human primates, deer, procyonids, and marsupials. Here, we investigated the occurrence of Onchocercidae in wild felids (i.e., Panthera onca, Puma concolor, Herpailurus yagouaroundi, Leopardus geoffroyi, Leopardus guttulus, Leopardus pardalis, Leopardus wiedii, Leopardus munoai) from different locations in Brazil. Overall, 82 samples (n = 63 blood; n = 19 tissues) were molecularly screened for cytochrome c oxidase subunit-1 (cox1) gene. Four (i.e., 4.8%) wild felid samples were positive, and at BLAST analysis, the obtained sequences showed varying percentage of nucleotide identity with the genera Brugia (i.e., 87-88%), Setaria (i.e., 89%), and D. immitis (i.e., 94.4%). Phylogenetic analyses clustered sequences obtained into three distinct clades, one with D. immitis and the remaining two with other Onchocercidae spp. Data herein obtained highlight the need for a more comprehensive understanding of the diversity and biology of Onchocercidae in South America in order to assess the potential impact that these species may have for domestic and wild animals, as well as humans.


Asunto(s)
Dirofilaria immitis , Dirofilariasis , Felidae , Animales , Brasil/epidemiología , Felidae/parasitología , Dirofilariasis/parasitología , Dirofilariasis/epidemiología , Dirofilaria immitis/genética , Dirofilaria immitis/aislamiento & purificación , Dirofilaria immitis/clasificación , Filogenia , Complejo IV de Transporte de Electrones/genética , Animales Salvajes/parasitología , Análisis de Secuencia de ADN , ADN de Helmintos/genética , Datos de Secuencia Molecular
2.
Parasitol Res ; 123(1): 88, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38190005

RESUMEN

Trypanosoma evansi is a widespread and neglected zoonotic parasite that affects domestic and wild animals, causing a disease commonly known as "surra." The Brazilian Pantanal wetland is recognized as an enzootic area for this protozoan, yet recognizing the importance of reservoir hosts also in order to prevent zoonotic outbreaks. This study aimed to assess the occurrence of T. evansi in jaguars (Panthera onca) from the Brazilian Pantanal wetland and explore associated clinical and hematological manifestations. A total of 42 animals were screened by PCR and sequenced for species identification when positive. Trypanosoma evansi was detected in six free-ranging jaguars (six positive animals of 42 captures and 16 recaptures), representing the first molecular evidence of such infection in this animal species. Our findings suggest that jaguars may act as reservoir hosts of T. evansi in the Brazilian Pantanal wetland. The better understanding of the role of wildlife in the epidemiology of T. evansi is also of importance to future reintroduction and translocation programs toward wildlife conservation efforts.


Asunto(s)
Panthera , Trypanosoma , Animales , Brasil/epidemiología , Humedales , Trypanosoma/genética , Animales Salvajes
3.
Parasitol Res ; 122(12): 2951-2956, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37823992

RESUMEN

Nematode species of the genus Dracunculus (Spirurida: Dracunculoidea) infect tissues and body cavities of reptiles, domestic and wild carnivores, and humans. The definitive hosts acquire the infection by ingesting intermediate (i.e., cyclopoid copepod) or paratenic (i.e., amphibians and fishes) hosts. Here we report the jaguar (Panthera onca) as a potential new host for Dracunculus sp. The nematode was collected from an ulcerated cutaneous nodule on the left anterior limb of a female jaguar in the municipality of Miranda, Mato Grosso do Sul state, Brazil. Based on the morphology of first stage larvae collected from a small fragment of the uterus of the adult nematode, the species was identified as Dracunculus sp. Reichard, 1759. Additionally, the morphological identification was molecularly confirmed by sequencing the cox1 gene. This report advocates for further investigations into the transmission cycle of this parasite in the Brazilian Pantanal wetland, considering the role of wildlife hosts and the zoonotic potential of Dracunculus species in that area.


Asunto(s)
Dracunculoidea , Panthera , Animales , Humanos , Femenino , Animales Salvajes , Dracunculus , Peces , Brasil
4.
J Mammal ; 104(2): 239-251, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37032705

RESUMEN

We conducted the first long-term and large-scale study of demographic characteristics and reproductive behavior in a wild jaguar (Panthera onca) population. Data were collected through a combination of direct observations and camera trapping on a study area that operates both as a cattle ranch and ecotourism destination. Jaguars exhibited two birth peaks: April/May and October/November, that are the end and the beginning of the wet season in the Pantanal, respectively. The average litter size was 1.43 ± 0.65. Single cubs made up a total of 65.7% of the births, and we found a slight predominance of females (1.15:1 ratio) in litters. The mean age at independence was 17.6 ± 0.98 months, with sex-biased dispersal, with all males (n = 27) leaving the natal home range and 63.6% of females exhibiting philopatry. The interbirth intervals were 21.8 ± 3.2 months and the mean age at first parturition was 31.8 ± 4.2 months. Our results estimated a lifetime reproductive success for female jaguars of 8.13 cubs. Our observations also indicate that female jaguars can display mating behavior during cub rearing or pregnancy, representing 41.4% of the consorts and copulations recorded. We speculate that this behavior has evolved as a defense against infanticide and physical harm to the female. To our knowledge, this is the first time that such behavior is described for this species. All aggressive interactions between females involved the presence of cubs, following the offspring-defense hypothesis, that lead to territoriality among females in mammals, regardless of food availability. In the face of growing threats to this apex predator, this work unveils several aspects of its natural history, representing a baseline for comparison with future research and providing critical information for population viability analysis and conservation planning in the long term.


Este é o primeiro estudo de longo prazo e em grande escala de características demográficas e de comportamento reprodutivo em uma população selvagem de onças-pintadas (Panthera onca). Os dados foram coletados por meio de uma combinação de observações diretas e armadilhamentos fotográficos em uma área de estudo que atua tanto como fazenda de pecuária quanto como destino ecoturístico. As onças-pintadas apresentaram dois picos de nascimento: abril/maio e outubro/novembro, que são o final e o início da estação chuvosa no Pantanal, respectivamente. O tamanho médio da ninhada foi 1.43 ± 0.65. Filhotes únicos representaram um total de 65.7% dos nascimentos, e encontramos uma ligeira predominância de fêmeas (proporção 1.15:1) nas ninhadas. A idade média de independência foi de 17.6 ± 0.98 meses, com uma dispersão sexo-assimétrica, com todos os machos (n = 27) deixando a área natal e 63.6% das fêmeas apresentando filopatria. O intervalo entre ninhadas foi de 21.8 ± 3.2 meses e a idade média da primeira cria foi de 31.8 ± 4.2 meses. Nossos resultados estimaram um sucesso reprodutivo médio ao longo da vida para onças-pintadas fêmeas de 8.13 filhotes. Nossas observações também indicam que as onças-pintadas fêmeas podem apresentar comportamento de acasalamento durante a criação dos filhotes ou da gestação, representando 41.4% das cortes e cópulas registradas. Especulamos que esse comportamento tenha evoluído como uma defesa contra infanticídio e danos físicos à fêmea. Segundo nosso conhecimento, está é a primeira vez que tal comportamento é descrito para esta espécie. Todas as interações agressivas entre fêmeas envolveram a presença de filhotes, seguindo a hipótese de defesa da prole, que levam à territorialidade entre fêmeas em mamíferos, independentemente da disponibilidade de alimento. Diante das crescentes ameaças a este predador de topo, este trabalho revela vários aspectos de sua história natural, representando uma base de comparação com pesquisas futuras e fornecendo informações críticas para a análise de viabilidade populacional e planejamento de conservação em longo prazo.

5.
Curr Biol ; 31(15): 3457-3466.e4, 2021 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-34237270

RESUMEN

Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function.1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.


Asunto(s)
Efectos Antropogénicos , Actividad Motora , Panthera , Conducta Espacial , Animales , Conservación de los Recursos Naturales , Ecología , Ecosistema , Masculino
6.
Ecology ; 99(7): 1691, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29961270

RESUMEN

The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation-scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species' distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human-modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator-prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long-term conservation efforts for this ecologically important species. There are no costs, copyright, or proprietary restrictions associated with this data set. When using this data set, please cite this article to recognize the effort involved in gathering and collating the data and the willingness of the authors to make it publicly available.


Asunto(s)
Panthera , Animales , Ecología , Femenino , Humanos , Masculino , Movimiento
7.
An Acad Bras Cienc ; 90(2 suppl 1): 2129-2139, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28832728

RESUMEN

The Pantanal is the largest inland wetland in the world and is under increasing anthropogenic threats, including long-term regionally intensive gold mining practices. Gold mining activities are known to cause the release of harmful pollutants such as mercury (Hg) to the surrounding environment. Jaguars (Panthera onca (Linnaeus, 1758)) are apex predators, and therefore show great potential to accumulate Hg by biomagnification. We hypothesize that total Hg content in the fur of jaguars from two sites within the Brazilian Pantanal would be significantly different as a function of distance from active gold mining operations. The Hg content was determined by fluorescence spectrometry. The mean ± SD Hg content in jaguars from the study site influenced by gold mining (SB) was compared to jaguars sampled in the area free of gold mining activities (CA) using a one-way ANOVA. The mean Hg content in jaguars from SB (673.0 ± 916.8 µg g-1) is significantly different from jaguars sampled in CA (29.7 ± 23.3 µg g-1), p = 0.03. The maximum recorded content of Hg was 2,010.4 ± 150.5 µg g-1, highest level ever recorded in a wild animal. The data indicate that Hg is an important threat to jaguars within at-risk regions of the Pantanal.

8.
Biota Neotrop. (Online, Ed. ingl.) ; 17(2): e20170358, 2017. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1038840

RESUMEN

Abstract Jaguar populations have been declining in Brazil mostly due to habitat loss and fragmentation, conflict with humans, poaching and reduction of prey. This is dramatically true in the Atlantic Forest, where occurrence of this large felid is now restricted to very few remaining areas. We used a non-invasive DNA analysis to search through felid scats collected in the Santa Virginia Unit (SVU) of the Serra do Mar State Park, to test for the potential presence of jaguar there. Our results indicated at least three individuals (two females and one male) inside SVU, thus confirming at least temporary presence of this top predator in this important protected area. It is now crucial to intensify studies in that area and surroundings, to evaluate the status of these individuals and identify conservation needs to urgently improve the prospects for the establishment of a resident population, allowing it to expand to adjoining units of the Serra do Mar State Park and Serra da Bocaina National Park.


Resumo As populações de onça-pintada têm sofrido declínio populacional devido a perda e fragmentação de habitat, por conflito com humanos, através da caça e pela redução da disponibilidade de suas presas. Isso é particularmente drástico no bioma Mata Atlântica, onde a ocorrência desse grande felino está atualmente restrita a poucos remanescentes. Utilizamos análise de DNA a partir de amostras de fezes para verificar a pontencial presença da espécie no Núcleo Santa Virgínia (NSV) do Parque Estadual da Serra do Mar. Os resultados indicaram a ocorrência pelo menos esporádica de três indivíduos (duas fêmas e um macho) no interior do NSV. Com isso, se torna crucial agora intensificar estudos naquela unidade e em áreas adjacentes, para avaliar a situação desses indivíduos e identificar as necessidades mais urgentes de conservação para melhorar a probabilidade de estabelecimento de uma população residente da espécie, permitindo que ela possa expandir para unidades de conservação vizinhas, como outros núcleos do Parque Estadual da Serra do Mar e o Parque Nacional Serra da Bocaina.

9.
PLoS One ; 11(12): e0168176, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28030568

RESUMEN

Accurately estimating home range and understanding movement behavior can provide important information on ecological processes. Advances in data collection and analysis have improved our ability to estimate home range and movement parameters, both of which have the potential to impact species conservation. Fitting continuous-time movement model to data and incorporating the autocorrelated kernel density estimator (AKDE), we investigated range residency of forty-four jaguars fit with GPS collars across five biomes in Brazil and Argentina. We assessed home range and movement parameters of range resident animals and compared AKDE estimates with kernel density estimates (KDE). We accounted for differential space use and movement among individuals, sex, region, and habitat quality. Thirty-three (80%) of collared jaguars were range resident. Home range estimates using AKDE were 1.02 to 4.80 times larger than KDE estimates that did not consider autocorrelation. Males exhibited larger home ranges, more directional movement paths, and a trend towards larger distances traveled per day. Jaguars with the largest home ranges occupied the Atlantic Forest, a biome with high levels of deforestation and high human population density. Our results fill a gap in the knowledge of the species' ecology with an aim towards better conservation of this endangered/critically endangered carnivore-the top predator in the Neotropics.


Asunto(s)
Especies en Peligro de Extinción , Fenómenos de Retorno al Lugar Habitual , Movimiento , Panthera/fisiología , Conducta Predatoria , Conducta Espacial , Clima Tropical , Animales
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