Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 37
Filter
Add more filters











Publication year range
1.
Acta Trop ; 257: 107309, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38955321

ABSTRACT

Bats are the second most diverse order of mammals and play a central role in ecosystem dynamics. They are also important reservoirs of potentially zoonotic microorganisms, of which rabies virus is the most lethal among the bat-transmitted zoonotic pathogens. Importantly, recent outbreaks of human rabies have been reported from the Brazilian Amazon. Here we present a survey of bat species and rabies virus (RABV) circulation in a bat assemblage in the Marajó region, northern Brazil. Using data from mist-net captures and bioacoustic sampling, 56 bat species were recorded along the Jacundá River basin over a 10-day expedition in November 2022. For the investigation of RABV, we used the direct fluorescent antibody test (DFAT) and the rapid fluorescent focus inhibition test (RFFIT). In total, 159 bat individuals from 22 species were investigated for RABV. Five adults of the common vampire bat, Desmodus rotundus, showed RABV-specific antibodies in serum samples. Additionally, we report on local residents with injuries caused by D. rotundus bites and the occurrence of colonies of non-hematophagous bats from different species roosting inside human residences. This scenario raises concerns about the risks of new cases of human rabies and other zoonotic diseases associated with bats in the region and highlights the need for epidemiological surveillance and mitigation measures to prevent outbreaks of emerging infectious diseases.


Subject(s)
Antibodies, Viral , Chiroptera , Disease Outbreaks , Rabies virus , Rabies , Zoonoses , Chiroptera/virology , Animals , Brazil/epidemiology , Rabies virus/immunology , Rabies virus/isolation & purification , Rabies virus/classification , Rabies/epidemiology , Rabies/veterinary , Rabies/virology , Humans , Zoonoses/epidemiology , Zoonoses/virology , Antibodies, Viral/blood , Female , Male , Adult , Middle Aged , Adolescent
2.
Ecol Evol ; 14(6): e11419, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38932963

ABSTRACT

Myotis originated during the Oligocene in Eurasia and has become one of the most diverse bat genera, with over 140 species. In the case of neotropical Myotis, there is a high degree of phenotypic conservatism. This means that the taxonomic and geographic limits of several species are not well understood, which constrains detailed studies on their ecology and evolution and how to effectively protect these species. Similar to other organisms, bats may respond to climate change by moving to different areas, adapting to new conditions, or going extinct. Ecological niche models have become established as an efficient and widely used method for interpolating (and sometimes extrapolating) species' distributions and offer an effective tool for identifying species conservation requirements and forecasting how global environmental changes may affect species distribution. How species respond to climate change is a key point for understanding their vulnerability and designing effective conservation strategies in the future. Thus, here, we assessed the impacts of climate change on the past and future distributions of two phylogenetically related species, Myotis ruber and Myotis keaysi. The results showed that the species are influenced by changes in temperature, and for M. ruber, precipitation also becomes important. Furthermore, M. ruber appears to have been more flexible to decreases in temperature that occurred in the past, which allowed it to expand its areas of environmental suitability, unlike M. keaysi, which decreased and concentrated these areas. However, despite a drastic decrease in the spatial area of environmental suitability of these species in the future, there are areas of potential climate stability that have been maintained since the Pleistocene, indicating where conservation efforts need to be concentrated in the future.

4.
Zookeys ; 1174: 273-287, 2023.
Article in English | MEDLINE | ID: mdl-37614246

ABSTRACT

Histiotus is a Neotropical genus of bat that currently includes 11 species. The systematics of Histiotus has been the focus of several studies over the last decades. However, no broad systematic revision has been made, and taxonomic issues such as synonymies, use of subspecies, and specimens that do not fit the description of valid species still persist, as pointed out by several authors. Histiotusalienus was described in 1916 and is known only by the holotype. Here we present a second record of H.alienus and an amended diagnosis of this species. We use qualitative, quantitative, and morphometric analyses based on data from 184 specimens of Histiotus and almost all valid species. Our amended diagnosis establishes the taxonomic limits of H.alienus, as well as a comprehensive comparison with congeners. We also explore new diagnostic characters for H.alienus and provide a few notes on the natural history of this species. Our results highlight skull similarities among Histiotus species and reinforce the usefulness of external morphology for their correct identification. Despite our new insights into the taxonomy of the genus, several taxonomic issues remain, and a comprehensive revision of the genus is needed.

5.
Biosens Bioelectron ; 232: 115291, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-37060864

ABSTRACT

Rabies is a lethal zoonotic disease caused by rabies virus (RABV) that affects human health and the economy. RABV is transmitted mainly by bats in Brazil, and surveillance in remote areas is hampered by the difficulty of properly collecting samples during fieldwork and the diagnosis is performed in laboratory conditions. Here, we report a portable electrochemical biosensor based on nucleic acid interactions for RABV detection in nasopharyngeal swab samples. The working electrode of the biosensor is composed of reduced graphene oxide (rGO) thin-film immobilized with cDNA through pi-pi stacking to enhance virus detection and specificity. Sensor performance was determined using RNA, and swab samples from bats. RNA detection shows good selectivity, and quantification presents a highly linear calibration curve (R2 = 0.990) using a concentration range of 0.145-25.39 ng/µL. A LOD of 0.104 ng/µL was reached with a sensitivity of 0.321 µA (ng/µL)-1. RABV detection in nasopharyngeal swab samples showed a good difference of positive sample from negative with a response time in seconds, ultra-fast detection compared to known techniques. Three biosensor groups were identified and named after physic-chemical surface characterization as: GO-1, GO-2, and rGO; with best performance for rGO group due to its sp2 hybridized network. Thus, we have successfully fabricated a promising electrochemical biosensor for fast in-situ detection of the RABV in swab samples, which can be expanded to other enveloped viruses that have RNA.


Subject(s)
Biosensing Techniques , Chiroptera , Graphite , Rabies virus , Rabies , Animals , Humans , Rabies virus/genetics , Chiroptera/genetics , Rabies/diagnosis , Rabies/veterinary , Rabies/epidemiology , Graphite/chemistry , RNA , Nasopharynx
6.
Pathogens ; 12(1)2023 Jan 02.
Article in English | MEDLINE | ID: mdl-36678419

ABSTRACT

Mixed infections by different Trypanosoma species or genotypes are a common and puzzling phenomenon. Therefore, it is critical to refine the diagnostic techniques and to understand to what extent these methods detect trypanosomes. We aimed to develop an accessible strategy to enhance the sensitivity of the hemoculture, as well as to understand the limitations of the hemoculture and the blood clot as a source of parasitic DNA. We investigated trypanosomatid infections in 472 bats by molecular characterization (18S rDNA gene) of the DNA obtained from the blood clot and, innovatively, from three hemoculture sample types: the amplified flagellates ("isolate"), the pellet of the culture harvested in its very initial growth stage ("first aliquot"), and the pellet of non-grown cultures with failure of amplification ("sediment"). We compared (a) the characterization of the flagellates obtained by first aliquots and isolates; and (b) the performance of the hemoculture and blood clot for trypanosomatid detection. We observed: (i) a putative new species of Bodo in Artibeus lituratus; (ii) the potential of Trypanosoma cruzi selection in the hemoculture; (iii) that the first aliquots and sediments overcome the selective pressure of the hemoculture; and (iv) that the blood clot technique performs better than the hemoculture. However, combining these methods enhances the detection of single and mixed infections.

7.
Parasitology ; 149(11): 1487-1504, 2022 09.
Article in English | MEDLINE | ID: mdl-35929484

ABSTRACT

Cruzia tentaculata is a helminth parasite of marsupials and has a wide geographic distribution from Mexico to Argentina. The aim of this study was to analyse the genetic population structure of this nematode along the Atlantic Forest biome. Cruzia tentaculata specimens were recovered from Didelphis aurita, Didelphis albiventris and Philander quica in 9 localities. Morphological and morphometric data were investigated for phenotypic diversity among localities and hosts using multivariate discriminant analysis of principal components. Phylogenetic relationships of C. tentaculata were determined using maximum likelihood and Bayesian inference. The population structure was analysed by fixation indices, molecular variance analysis, Tajima's D and Fu's Fs neutrality tests, Mantel tests and Bayesian clustering analysis. A higher significant morphometric difference for males was observed between localities. In the haplogroup networks, 2 groups were recovered, separating locations from the north and from the south/southeast. The morphometric variation in C. tentaculata between different localities was compatible with this north and southeast/south pattern, suggesting adaptation to different ecological conditions. Population genetic analyses suggested a pattern of evolutionary processes driven by Pleistocene glacial refugia in the northeast and southeast of the Atlantic Forest based on the distribution of genetic diversity.


Subject(s)
Ascaridida , Didelphis , Marsupialia , Nematoda , Parasites , Animals , Ascaridida/anatomy & histology , Bayes Theorem , Didelphis/parasitology , Forests , Genetic Variation , Genetics, Population , Male , Phylogeny , South America
8.
Biodivers Data J ; 10: e82139, 2022.
Article in English | MEDLINE | ID: mdl-35586260

ABSTRACT

Conceição dos Ouros is located in the Mantiqueira mountain range (elevation: 831‒1443 m a.s.l.), State of Minas Gerais, southeast Brazil. The largest two Atlantic Forest remnants of the Municipality of Conceição dos Ouros total more than 2,000 ha and the main vegetation type is seasonal semi-deciduous forest, isolated by a matrix of agricultural fields and pasture. The Municipality does not have any protected areas and is located in a highly fragmented region, albeit considered of special importance for the conservation of terrestrial vertebrates in the State of Minas Gerais. Due to a cooperation with the Municipality of Conceição dos Ouros to carry out a survey of the local biodiversity, in this study we present the results of the survey of medium- and large-sized terrestrial mammals from the two forest remnants in the region. Sampling was performed from July 2019 to August 2021 and comprised a camera trap survey, active searching including direct (e.g. carcass sightings) and indirect (e.g. footprints and faeces) evidence of species presence and interviews with residents. Twenty-nine native and two non-native species were documented. Ten species are in some category of threat of extinction at regional, national or global levels. This is the first survey of the terrestrial mammal fauna in the area of Conceição dos Ouros and results could be helpful in designing conservation strategies at the local scale.

9.
Zookeys ; 1105: 127-164, 2022.
Article in English | MEDLINE | ID: mdl-36760324

ABSTRACT

Myotis comprises a diverse group of vespertilionid bats with worldwide distribution. Neotropical Myotis have an accentuated phenotypic conservatism, which makes species delimitation and identification difficult, hindering our understanding of the diversity, distribution, and phylogenetic relationships of taxa. To encourage new systematic reviews of the genus, a catalogue of the primary types and names is presented, current and in synonymy, for Neotropical Myotis. Currently 33 valid species (and three subspecies) are recognized, and their primary types are deposited in 12 scientific collections in the USA (30 types), Brazil (two types), England (two types), and France (one type). The names of 29 Neotropical Myotis species currently in synonymy were found. However, it is possible that some synonyms represent independent evolutionary lineages, considering recent results provided by taxonomic revisions.


ResumoMyotis compreende um grupo diverso de morcegos vespertilionídeos amplamente distribuídos ao redor do planeta. Myotis neotropicais têm um acentuado conservatismo fenotípico, o que dificulta a delimitação e identificação de espécies a partir de caracteres morfológicos, criando barreiras para a compreensão da diversidade, distribuição e relações filogenéticas entre os táxons. Visando encorajar novas revisões sistemáticas para o gênero, é apresentado este catálogo de nomes e tipos primários, válidos e sob sinonímia, para Myotis neotropicais. Atualmente, são reconhecidas 33 espécies válidas (e três subespécies) e seus tipos estão depositados em 12 coleções científicas nos EUA (30 tipos), Brasil (2 tipos), Inglaterra (2 tipos) e França (1 tipo). Compilamos 29 nomes de espécies de Myotis atualmente sob sinonímia. Entretanto, é possível que alguns desses sinônimos possam representar linhagens evolutivas independentes, considerando resultados recentes de revisões taxonômicas.

10.
Biodivers Data J ; 10: e86756, 2022.
Article in English | MEDLINE | ID: mdl-36761537

ABSTRACT

The Pedra Branca Forest is in a highly urbanised region of the central portion of Rio de Janeiro City and comprises the largest urban forest in the world (> 12,000 ha). The local flora and fauna are protected by three conservation units and the Estação Biológica Fiocruz Mata Atlântica (EFMA), which comprises 462 hectares on the east side of the remnant. The local biodiversity is still little known compared to other Atlantic Forest remnants from the Rio de Janeiro State. Here, we provide results of a survey of medium- and large-sized terrestrial mammals from the EFMA. In addition, we analysed the distribution of this fauna along three habitat types defined as Peridomicile, Transitional Forest and Forest Core. Sampling was performed from 2017 to 2020 and comprised a camera-trap survey, interviews with residents and local workers and occasional records. Results include occurrence records for 16 autochthonous and one allochthonous (Callithrix sp.) wild mammals, which are distributed into 14 families and seven orders, in addition to the presence of free-ranging domestic dogs and cats. Four species are in some category of threat of extinction at national or global levels. Amongst them, Leontopithecusrosalia (first record for the Rio de Janeiro City in more than a century) and Leopardusguttulus are classified as Vulnerable by IUCN. Most wild native species were registered in the three habitat types, but with differences in the frequency of records. Our results indicate that the presence of domestic dogs and cats influenced the species composition in each area, with Nasuanasua, Dasyproctaleporina and Didelphisaurita less frequent in places where domestic dogs and cats are more frequent. This is the first systematic effort to understand the occurrence and distribution of mid- and large-sized mammals in the Pedra Branca Forest.

SELECTION OF CITATIONS
SEARCH DETAIL