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1.
Genet Mol Biol ; 47(1): e20230252, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38446984

RESUMO

The progressive fragmentation and loss of habitats represent the main threats for endangered species, causing genetic consequences that may have potential implications for a population's long-term persistence. Large mammals are the most affected species among vertebrates. The giant armadillo Priodontes maximus is a large South American mammal threatened species, showing nocturnal, solitary and fossorial behavior, occurring at low population densities, and its population dynamics are still poorly known. In this study, we carried out the first assessment of genetic variability and population genetic structure of the species, using a panel of 15 polymorphic microsatellites developed by high-throughput genome sequencing. The spatial Bayesian clustering, Fst and Dest results indicated the presence of two genetic clusters (K = 2) in the study area. These results suggest a reduction in gene flow between individuals inhabiting the Brazilian savanna (Cerrado) and the Pantanal wetlands, with the increased human-driven habitat modifications possibly contributing for this scenario. A bottleneck signal was detected in both populations, and a subpopulation structuring in the Cerrado may also be reflecting consequences of the extensive habitat modifications. Findings from this study provide important and useful information for the future maintenance of genetic diversity and long-term conservation of this flagship species.

2.
Parasitol Res ; 122(12): 3169-3180, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37848747

RESUMO

Xenarthra mammals can be found from southern North America to southern South America, including all Brazilian biomes. Although it has been shown that Xenarthra mammals can play a role as reservoirs for several zoonotic agents, few studies investigate the diversity of piroplasmids (Apicomplexa: Piroplasmida) in this group of mammals. Taking into account that piroplasmids can cause disease in animals and humans, understanding the prevalence and diversity of piroplasmids in Xenarthra mammals would contribute to conservation efforts for this group of animals as well as to infer risk areas for transmission of emergent zoonosis. The present study aimed to investigate the occurrence and molecular identity of piroplasmids in free-living mammals of the Superorder Xenarthra from four Brazilian states (Mato Grosso do Sul, São Paulo, Rondônia, and Pará). For this, DNA was extracted from blood or spleen samples from 455 animals. A nested PCR based on the 18S rRNA gene was used as screening for piroplasmids. Of the 455 samples analyzed, 25 (5.5%) were positive. Additionally, PCR assays based on 18S rRNA near-complete, cox-1, cox-3, hsp70, cytB, ß-tubulin genes and the ITS-1 intergenic region were performed. Five out of 25 positive samples also tested positive for ITS-1-based PCR. The phylogenetic analysis positioned three 18S rRNA sequences detected in Priodontes maximus into the same clade of Babesia sp. detected in marsupials (Didelphis albiventris, Didelphis marsupialis, and Monodelphis domestica) and Amblyomma dubitatum collected from opossums and coatis in Brazil. On the other hand, the 18S rRNA sequence obtained from Dasypus novemcinctus was closely related to a Theileria sp. sequence previously detected in armadillos from Mato Grosso State, grouping in a subclade within the Theileria sensu stricto clade. In the phylogenetic analysis based on the ITS-1 region, the sequences obtained from Myrmecophaga tridactyla and Tamandua tetradactyla were placed into a single clade, apart from the other piroplasmid clades. The present study demonstrated the molecular occurrence of Piroplasmida in anteaters and Babesia sp. and Theileria sp. in armadillos from Brazil.


Assuntos
Babesia , Didelphis , Marsupiais , Piroplasmida , Theileria , Xenarthra , Animais , Humanos , Brasil/epidemiologia , Tatus , Filogenia , RNA Ribossômico 18S/genética , Theileria/genética , Babesia/genética , Piroplasmida/genética
3.
Pathogens ; 11(8)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36015039

RESUMO

Knowledge of reproductive health in wild southern tamanduas (Tamandua tetradactyla; Mammalia: Myrmecophagidae) is fragmentary. During necropsies of roadkill xenarthran species in Brazil, a case of ovarian filariasis in an adult female southern tamandua was observed. Macroscopically, both ovaries were irregularly enlarged and had numerous smooth protuberances. Histologically, the affected ovarian parenchyma presented adult nematodes (including females with microfilaria) surrounded by pleocellular inflammatory infiltrates. The morphological characteristics of the nematodes were consistent with the superfamily Filarioidea (order Spirurida). The adjacent ovarian parenchyma had developing and atretic follicles at different stages of maturation. Filarial nematodes were not observed in other tissues. The cause of death of this tamandua was fatal acute polytrauma as a consequence of the motor vehicle collision. This case adds to a prior report of ovarian filariasis in two southern tamanduas in Nicaragua and Guatemala, dating back almost 100 years, and suggests filarial infections could potentially have an impact on reproductive success in southern tamanduas and possibly other xenarthrans. Several xenarthran species are under different levels of threat and knowledge of their basic reproductive health is crucial for conservation programs.

4.
Ecology ; 103(9): e3738, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35567292

RESUMO

The Amazon forest has the highest biodiversity on Earth. However, information on Amazonian vertebrate diversity is still deficient and scattered across the published, peer-reviewed, and gray literature and in unpublished raw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazon regions to compile the most extensive data set of inventories of mammal, bird, and reptile species ever assembled for the area. The complete data set comprises 154,123 records of 317 species (185 birds, 119 mammals, and 13 reptiles) gathered from surveys from the Amazonian portion of eight countries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru, Suriname, and Venezuela). The most frequently recorded species per taxa were: mammals: Cuniculus paca (11,907 records); birds: Pauxi tuberosa (3713 records); and reptiles: Tupinambis teguixin (716 records). The information detailed in this data paper opens up opportunities for new ecological studies at different spatial and temporal scales, allowing for a more accurate evaluation of the effects of habitat loss, fragmentation, climate change, and other human-mediated defaunation processes in one of the most important and threatened tropical environments in the world. The data set is not copyright restricted; please cite this data paper when using its data in publications and we also request that researchers and educators inform us of how they are using these data.


Assuntos
Florestas , Mamíferos , Animais , Biodiversidade , Aves , Brasil , Humanos , Répteis , Vertebrados
5.
Transbound Emerg Dis ; 69(5): e1877-e1891, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35298081

RESUMO

Although mammals of the superorder Xenarthra are considered hosts of a wide range of zoonotic agents, works aiming at investigating the role of these animals as hosts for bacteria with zoonotic potential are rare. The present study aimed to investigate the occurrence and molecularly characterize Coxiella burnetii and haemoplasma (haemotropic mycoplasmas) DNA in blood and spleen samples from 397 free-living Xenarthra mammals (233 sloths, 107 anteaters and 57 armadillos) in five Brazilian states (Mato Grosso do Sul, São Paulo, Pará, Rondônia and Rio Grande do Sul). All biological samples from Xenarthra were negative in the qPCR for Coxiella burnetii based on the IS1111 gene. The absence of C. burnetii DNA in blood and spleen samples from Xenarthra suggests that these mammals may not act as possible hosts for this agent in the locations studied. When performed conventional PCR assays for the endogenous (gapdh) mammalian gene, 386 samples were positive. When screened by molecular assays based on the 16S rRNA gene of haemoplasmas, 81 samples were positive, of which 15.54% (60/386) were positive by conventional PCR and 5.44% (21/386) were positive by real-time PCR; three samples were positive in both assays. Of these, 39.74% (31/78) were also positive for the 23S rRNA gene and 7.69% (6/78) for the haemoplasma RNAse P gene. Among the samples positive for haemoplasmas, 25.64% (20/78) were obtained from anteaters (Tamandua tetradactyla and Myrmecophaga tridactyla), 39.74% (31/78) from sloths (Bradypus tridactylus, Bradypus sp. and Choloepus sp.) 34.61% (27/78) from armadillos (Priodontes maximus, Euphractus sexcinctus and Dasypus novemcinctus). A haemoplasma 16S rRNA sequence closely related and showing high identity (99.7%) to Mycoplasma wenyonii was detected, for the first time, in B. tridactylus. Based on the low identity and phylogenetic positioning of 16S rRNA and 23S rRNA sequences of haemoplasmas detected in anteaters and armadillos, the present study showed, for the first time, the occurrence of putative new Candidatus haemotropic Mycoplasma spp. ("Candidatus Mycoplasma haematotetradactyla" and "Candidatus Mycoplasma haematomaximus") in Xenarthra mammals from Brazil.


Assuntos
Coxiella burnetii , Infecções por Mycoplasma , Mycoplasma , Bichos-Preguiça , Xenarthra , Animais , Tatus/genética , Brasil/epidemiologia , Coxiella burnetii/genética , DNA , Mycoplasma/genética , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/veterinária , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Ribonuclease P/genética
6.
Integr Zool ; 17(2): 285-296, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33738919

RESUMO

Mammals can show conspicuous behavioral responses to thermal variation, including changes in movement patterns. We used an integrative approach to understand how environmental temperature can drive the movement behavior of a mammal with low capacity for physiological thermoregulation, the giant anteater (Myrmecophaga tridactyla). We tracked 52 giant anteaters in 7 areas throughout the Brazilian savannah. We estimated the distance moved, area used, use of forest areas, and mean environmental temperature for each monitoring day of each individual. We modeled these data with Mixed Structural Equations - considering the possible interactions between our variables and controlling for sex and body mass. Giant anteaters reduced displacement and increased forest use with decreasing environmental temperature, probably because of their low body heat production. It is possible that they reduce distance moved and area used by reducing the duration of activity. With decreasing temperature, forest habitats become warmer than open ones, besides buffer rain and chilly winds. Reducing displacement and using forests are important strategies to reduce body heat loss and the energetic costs of thermoregulation. However, decreasing movement can limit food access and, consequently, fitness. Therefore, we highlight the importance of forests as thermal shelters. With increasing frequency and intensity of extreme weather events, we showed the need to preserve forest patches to offer suitable conditions for tropical mammals' behavioral thermoregulation. In this context, policies favoring deforestation on Brazilian territory are especially worrisome. Finally, we emphasize the need of integrative approaches to understand the complex interactions between organisms and the environment.


Assuntos
Ecossistema , Vermilingua , Animais , Regulação da Temperatura Corporal , Florestas , Mamíferos , Temperatura
7.
Transbound Emerg Dis ; 69(4): 2045-2051, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34132049

RESUMO

The number of viral-associated neoplasms reported in wildlife has increased over the last decades, likely because of growing research efforts and a potentially greater burden of carcinogenic pathogens. Herein, we describe a primary gastric T-cell lymphoma in one free-ranging giant armadillo (Priodontes maximus) from Brazilian Pantanal infected by a novel gammaherpesvirus, proposed as Cingulatid gammaherpesvirus 1 (CiHV-1). By chromogenic in situ hybridisation against Epstein-Barr virus some neoplastic cells were labeled. Subsequently, a molecular screening was carried out to detect the occurrence of this pathogen in other giant armadillos in the same region. Overall, this novel virus was detected in 14.3% (3/21) of the tested giant armadillos. We suggest this herpesvirus, the first in Xenarthra, as a plausible aetiology of the neoplasm. The implications of CiHV-1 for this species are uncertain; while no outbreaks of disease have been recorded, the present study raises concerns. Further research is warranted to assess the real significance of CiHV-1 and its potential oncogenic role in this species.


Assuntos
Infecções por Vírus Epstein-Barr , Gammaherpesvirinae , Linfoma de Células T , Animais , Tatus , Brasil/epidemiologia , Infecções por Vírus Epstein-Barr/veterinária , Gammaherpesvirinae/genética , Herpesvirus Humano 4 , Linfoma de Células T/epidemiologia , Linfoma de Células T/veterinária
8.
PLoS One ; 16(8): e0253345, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34407068

RESUMO

Knowing the influence of intrinsic and environmental traits on animals' movement is a central interest of ecology and can aid to enhance management decisions. The giant anteater (Myrmecophaga tridactyla) is a vulnerable mammal that presents low capacity for physiological thermoregulation and uses forests as thermal shelters. Here, we aim to provide reliable estimates of giant anteaters' movement patterns and home range size, as well as untangle the role of intrinsic and environmental drivers on their movement. We GPS-tracked 19 giant anteaters in Brazilian savannah. We used a continuous-time movement model to estimate their movement patterns (described by home range crossing time, daily distance moved and directionality), and provide an autocorrelated kernel density estimate of home range size. Then, we used mixed structural equations to integratively model the effects of sex, body mass and proportion of forest cover on movement patterns and home range size, considering the complex net of interactions between these variables. Male giant anteaters presented more intensive space use and larger home range than females with similar body mass, as it is expected in polygynous social mating systems. Males and females increased home range size with increasing body mass, but the allometric scaling of intensity of space use was negative for males and positive for females, indicating different strategies in search for resources. With decreasing proportion of forest cover inside their home ranges, and, consequently, decreasing thermal quality of their habitat, giant anteaters increased home range size, possibly to maximize the chances of accessing thermal shelters. As frequency and intensity of extreme weather events and deforestation are increasing, effective management efforts need to consider the role of forests as an important thermal resource driving spatial requirements of this species. We highlight that both intrinsic and environmental drivers of animal movement should be integrated to better guide management strategies.


Assuntos
Eutérios/fisiologia , Comportamento de Retorno ao Território Vital , Distribuição Animal , Animais , Brasil , Ecossistema , Feminino , Florestas , Masculino , Modelos Biológicos , Comportamento Sexual Animal
10.
Sci Rep ; 11(1): 272, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432031

RESUMO

Knowledge of infectious diseases in wildlife provides important information for preventing potential outbreaks of zoonotic diseases. Adiaspiromycosis is a neglected human disease caused by dimorphic Onygenales fungi. The disease is produced by the inflammatory response against growing adiaspores, leading to granulomatous pneumonia. In humans, adiaspiromycosis is relevant in immunosuppressed patients. In animals, it is associated with pneumonia in fossorial species. Given the potential role of armadillos in the epidemiology of adiaspiromycosis, in this study, we sought to investigate the occurrence and pathological features of adiaspiromycosis in roadkilled armadillos. In total, 54 armadillo carcasses were suitable for postmortem pathologic examinations between February 2017 and 2020. Adiaspores, associated with granulomatous lesions, were observed in ten six-banded (Euphractus sexcinctus) and two southern naked-tailed armadillos (Cabassous unicinctus). A previously uncharacterized Onygenales species was molecularly identified in two E. sexcinctus. In summary, herein we report 12 cases of pulmonary adiaspiromycosis (PA) in two species of free-living armadillos in Brazil. Both, the morphology of the fungus, as well as the histopathological findings (granulomatous inflammatory response to adiaspores) are consistent with PA; however, as the molecular identification differs from the reported species, the potential impact of this fungus for human PA is unknown, and we cannot rule out its impact on public health.


Assuntos
Tatus/microbiologia , Pneumopatias Fúngicas/veterinária , Veículos Automotores , Animais , Brasil
11.
Chemosphere ; 270: 128644, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33121800

RESUMO

The giant anteater (Myrmecophaga tridactyla) can occur in both preserved and anthropogenic environments in Brazilian biomes. The Cerrado biome, where the samples were collected, is considered one of the world's biodiversity hotspots; however, a large part of it has been converted to pasture and agricultural land. In this environment, animals may be exposed to contaminants, such as mercury (Hg). Despite its immense biodiversity, there are few studies investigating Hg contamination in terrestrial mammals in Brazil. This study aimed to create a baseline for Hg levels in giant anteater fur and establish which biotic and abiotic variables can influence its concentration. Total Hg (THg) concentrations were determined by cold vapor atomic absorption spectrometry in 141 individuals sampled on highways between January and October 2017, in the state of Mato Grosso do Sul, Brazil. THg concentrations in fur ranged from 0.27 to 4.77 µg g -1. The decomposition stage of the carcasses and vehicular traffic volume on highways did not influence the THg concentrations. Juveniles presented lower THg concentrations than adults. A spatial pattern of higher concentrations in the eastern-southeastern region of the state was found, which could be related to anthropogenic impacts; however, no clear links have been established. The THg concentrations in giant anteaters' fur seems higher than expected considering the trophic position of the species. Despite this, the range was in accordance with studies of other Brazilian terrestrial mammals and within safe threshold levels. This study indicates the potential of utilizing roadkilled fauna to monitor large-scale contamination in wildlife.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Monitoramento Biológico , Brasil , Monitoramento Ambiental , Eutérios , Cabelo/química , Mercúrio/análise , Poluentes Químicos da Água/análise
12.
Sci Rep ; 10(1): 12615, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724088

RESUMO

Anaplasmataceae agents are obligatory intracellular Gram-negative α-proteobacteria that are transmitted mostly by arthropod vectors. Although mammals of the Superorder Xenarthra (sloths, anteaters, and armadillos) have been implicated as reservoirs for several zoonotic agents, only few studies have sought to detect Anaplasmataceae agents in this group of mammals. This study aimed to investigate the occurrence and genetic diversity of Anaplasma spp. and Ehrlichia spp. in blood and spleen samples of free-living Xenarthra from four different states in Brazil (São Paulo, Mato Grosso do Sul, Rondônia, and Pará). Nested and conventional PCR screening assays were performed to detect the rrs and dsb genes of Anaplasma spp. and Ehrlichia spp., respectively. The assays were positive in 27.57% (91/330) of the Anaplasma spp. and 24.54% (81/330) of the Ehrlichia spp. Of the 91 positive Anaplasma spp. samples, 56.04% were positive in a conventional PCR assay targeting the 23S-5S intergenic region. Phylogenetic and distance analyses based on the rrs gene allocated Anaplasma sequences from sloths captured in Rondônia and Pará states in a single clade, which was closely related to the A. marginale, A. ovis, and A. capra clades. The sequences detected in southern anteaters from São Paulo were allocated in a clade closely related to sequences of Anaplasma spp. detected in Nasua nasua, Leopardus pardalis, and Cerdocyon thous in Brazil. These sequences were positioned close to A. odocoilei sequences. Genotype analysis corroborated previous findings and demonstrated the circulation of two distinct Anaplasma genotypes in animals from north and southeast Brazil. The first genotype was new. The second was previously detected in N. nasua in Mato Grosso do Sul state. The intergenic region analyses also demonstrated two distinct genotypes of Anaplasma. The sequences detected in Xenarthra from Pará and Rondônia states were closely related to those in A. marginale, A. ovis, and A. capra. Anaplasma spp. sequences detected in Xenarthra from São Paulo and were allocated close to those in A. phagocytophilum. The analyses based on the dsb gene grouped the Ehrlichia spp. sequences with sequences of E. canis (São Paulo, Mato Grosso do Sul, and Pará) and E. minasensis (Rondônia and Pará). The data indicate the occurrence of E. canis and E. minasensis and two possible new Candidatus species of Anaplasma spp. in free-living mammals of the Superorder Xenarthra in Brazil.


Assuntos
Anaplasma/isolamento & purificação , Ehrlichia/isolamento & purificação , Xenarthra/microbiologia , Anaplasma/genética , Animais , Sequência de Bases , Teorema de Bayes , Brasil , DNA Intergênico/genética , Ehrlichia/genética , Geografia , Hidrólise , Funções Verossimilhança , Filogenia , Polimorfismo Genético , Temperatura
13.
Transbound Emerg Dis ; 67(5): 2020-2033, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32162470

RESUMO

The superorder Xenarthra consists of sloths, anteaters and armadillos, mammals originated from South America and currently distributed from the south of North America to the south of South America. The present study aimed to investigate the occurrence and genetic diversity of Bartonella spp. in blood and spleen samples from free-living Xenarthra mammals in the states of São Paulo (SP), Mato Grosso do Sul (MS), Rondônia (RO) and Pará (PA). Based on a quantitative real-time PCR (qPCR) assay, a Bartonella spp. nuoG gene fragment was detected in 1.51% (5/330) of the samples: 4 six-banded armadillos (Euphractus sexcinctus) sampled in the MS and 1 southern tamandua (Tamandua tetradactyla) sampled in the PA. Eight sequences (5 ftsZ, 2 gltA and 1 rpoB) were obtained in the conventional PCR assays. In both phylogenetic analyses based on Bayesian and distance (SplitsTree) methods, the obtained ftsZ, gltA and rpoB sequences were positioned in a distinct clade, but related to B. washoensis. The analysis of SplitsTree and genotype networks based on B. washoensis sequences from several hosts from various localities of the world showed that the sequences of the present study were allocated in a group separated from the other sequences, indicating that they probably originated from median vectors and large numbers of mutational events. Additionally, the analyses performed by BLAST showed low percentages of identities of the sequences obtained in the present study when compared to those previously deposited in GenBank. Therefore, we propose a new Candidatus to Bartonella occurring in Xenarthra in Brazil. The present study was the first to report the occurrence of Bartonella sp. in mammals of the superorder Xenarthra in the world, and it was the first to describe a new Candidatus related to B. washoensis in Brazil.

14.
Integr Zool ; 7(4): 356-372, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23253367

RESUMO

A population viability analysis (PVA) was conducted of the lowland tapir populations in the Atlantic Forest of the Pontal do Paranapanema region, Brazil, including Morro do Diabo State Park (MDSP) and surrounding forest fragments. Results from the model projected that the population of 126 tapirs in MDSP is likely to persist over the next 100 years; however, 200 tapirs would be required to maintain a viable population. Sensitivity analysis showed that sub-adult mortality and adult mortality have the strongest influence on the dynamics of lowland tapir populations. High road-kill has a major impact on the MDSP tapir population and can lead to population extinction. Metapopulation modeling showed that dispersal of tapirs from MDSP to the surrounding fragments can be detrimental to the overall metapopulation, as fragments act as sinks. Nevertheless, the model showed that under certain conditions the maintenance of the metapopulation dynamics might be determinant for the persistence of tapirs in the region, particularly in the smaller fragments. The establishment of corridors connecting MDSP to the forest fragments models resulted in an increase in the stochastic growth rate, making tapirs more resilient to threats and catastrophes, but only if rates of mortality were not increased when using corridors. The PVA showed that the conservation of tapirs in the Pontal region depends on: the effective protection of MDSP; maintenance and, whenever possible, enhancement of the functional connectivity of the landscape, reducing mortality during dispersal and threats in the unprotected forest fragments; and neutralization of all threats affecting tapirs in the smaller forest fragments.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Modelos Biológicos , Perissodáctilos/fisiologia , Fatores Etários , Animais , Brasil , Simulação por Computador , Tamanho da Ninhada de Vivíparos , Mortalidade , Densidade Demográfica , Dinâmica Populacional , Reprodução/fisiologia , Sensibilidade e Especificidade , Árvores
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