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1.
BMC Vet Res ; 14(1): 279, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30200947

RESUMO

BACKGROUND: The role of bats as reservoirs of zoonotic agents, especially pathogenic bacteria such as Bartonella and Coxiella, has been discussed around the world. Recent studies have identified bats as potential hosts of species from the proteobacteria phylum. In Brazil, however, the role of bats in the natural cycle of these agents is poorly investigated and generally neglected. In order to analyze the participation of bats in the epidemiology of diseases caused by Bartonella, Coxiella, Rickettsia, Anaplasma and Ehrlichia, we conducted a descriptive epidemiological study in three biogeographic regions of the Brazilian Atlantic Forest. RESULTS: Tissues of 119 bats captured in preserved areas in the states of Rio de Janeiro, Bahia and Santa Catarina from 2014 to 2015 were submitted to molecular analysis using specific primers. Bartonella spp. was detected in 22 spleen samples (18.5%, 95% CI: 11.9-26.6), whose phylogenetic analysis revealed the generation of at least two independent clusters, suggesting that these may be new unique genotypes of Bartonella species. In addition, four samples (3.4%, 95% CI: 0.9-8.3) were positive for the htpAB gene of C. burnetii [spleen (2), liver (1) and heart (1)]. Rickettsia spp., Anaplasma and Ehrlichia were not identified. This is the first study reporting C. burnetii and Bartonella spp. infections in bats from the Atlantic Forest biome. CONCLUSIONS: These findings shed light on potential host range for these bacteria, which are characterized as important zoonotic pathogens.


Assuntos
Bartonella/isolamento & purificação , Quirópteros/microbiologia , Coxiella/isolamento & purificação , Animais , Bartonella/genética , Infecções por Bartonella/epidemiologia , Brasil/epidemiologia , Coxiella/genética , DNA Bacteriano , Feminino , Florestas , Bactérias Gram-Negativas , Masculino , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Baço/microbiologia , Zoonoses/epidemiologia
3.
Int J Biometeorol ; 60(3): 421-33, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26219606

RESUMO

We evaluated the effects of climate seasonality from a thermal and water availability perspective on the activity patterns and resource use of Pecari tajacu and Tayassu pecari during wet and dry seasons in the northeastern Brazilian Pantanal. We used camera traps and temperature sensors to record species activity patterns in relation to temperature, established five habitat categories based on flooding intensity and local vegetation characteristics, assessed the activity patterns of each species in dry and wet periods and in artificial water bodies using circular statistical metrics, and calculated niche amplitude and overlap on three axes (temperature, time, and habitat) in both periods. Peccaries shared a strong resemblance in resource use and in their responses to seasonal variations in the tested gradients. The activity patterns of both species exhibited a significant correlation with air temperature on all the evaluated measures, and both species strongly reduced their activity when the air temperature exceeded 35 °C. High temperatures associated with low water availability were most likely responsible for the changes in species activity patterns, which resulted in an increased temporal overlap in habitat use throughout the dry season. However, the peccaries avoided intensively flooded habitats; therefore, the habitat gradient overlap was greater during the wet period. Our results show that an increase in niche overlap on the environmental gradient as a result of climatic seasonality may be partially compensated by a reduction in other niche dimensions. In this case, temporal partitioning appears to be an important, viable mechanism to reduce competition by potentially competing species.


Assuntos
Artiodáctilos , Comportamento Animal , Estações do Ano , Animais , Brasil , Ecossistema , Microclima , Tempo (Meteorologia)
4.
Parasit Vectors ; 11(1): 155, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29514680

RESUMO

BACKGROUND: Leishmaniasis represents an important public health problem in Brazil. The continuous process of urbanization and expansion of human activities in forest areas impacts natural habitats, modifying the ecology of some species of Leishmania, as well as its vectors and reservoirs and, consequently, changes the epidemiological pattern that contributes to the expansion of American cutaneous leishmaniasis in Brazil. Here, we discuss Lutzomyia (Nyssomyia) whitmani, the main vector of ACL, transmitting two dermotropic Leishmania species including Leishmania (Viannia) braziliensis and Leishmania (V.) shawi. METHODS: We used the maximum entropy niche modelling approach (MaxEnt) to evaluate the environmental suitability of L. (N.) whitmani and the transmission of ACL in Brazil, in addition to designing models for a future scenario of climate change. MaxEnt was used under the "auto-features" mode and the default settings, with 100-fold repetition (bootstrap). The logistic output was used with higher values in the habitat suitability map, representing more favourable conditions for the occurrence of L. (N.) whitmani and human cases of ACL. RESULTS: Two models were developed: the Lutzomyia (N.) whitmani model (LWM) and the American cutaneous leishmaniasis model (ACLM). LWM identified the species "preferential habitat" included regions with moderate annual precipitation (AP) between 1000-1600 mm, intermediate vegetation density (NDVI) values, mean temperature of the coldest quarter (MTCQ), between 15-21 °C, and annual mean temperature (AMT), between 19-24 °C. ACLM indicates that ACL is strongly associated with areas of intermediate density vegetation, areas with AP between 800-1200 mm, MTCQ above 16 °C and AMT below 23 °C. CONCLUSIONS: The models generated for L. (N.) whitmani and ACL indicated a satisfactory predictive capacity. Future projections of LWM indicate an expansion of climatic suitability for L. (N.) whitmani for the northern and southern regions of Brazil. Future projections of ACL indicate the ongoing process of disease expansion in the face of the predicted climatic changes and reinforce the broad geographical expanse of this disease in Brazil. The models were able to identify that a continuous process of environmental degradation favours the establishment of L. (N.) whitmani and the occurrence of ACL by a strong association of the vector(s) and ACL to areas of intermediate vegetation cover density.


Assuntos
Insetos Vetores/crescimento & desenvolvimento , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Psychodidae/crescimento & desenvolvimento , Animais , Brasil/epidemiologia , Mudança Climática , Exposição Ambiental , Humanos , Insetos Vetores/parasitologia , Modelos Estatísticos , Psychodidae/parasitologia , Temperatura
5.
PeerJ ; 4: e2456, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27672509

RESUMO

The development of species distribution models (SDMs) can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA) at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs) better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19%) of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

6.
Rev Bras Parasitol Vet ; 18 Suppl 1: 19-28, 2009 Dec.
Artigo em Português | MEDLINE | ID: mdl-20040186

RESUMO

Biodiversity studies allow ecosystem assessment and monitoring of environmental changes and impacts. Parasite diversity could reflect the host/ parasite coevolutionary process and the environment changes that permit the loss, gain or maintenance of species. This survey used species/morphotypes of helminths eggs found in feces from seven wild mammal species (the groups Dasypodidae and Large Cats, and Tamandua tetradactyla, Cebus apella, Alouatta caraya, Cerdocyon thous, Pecari tajacu) and from two domestic species (Canis familiaris and Sus scrofa), which occur within the Serra da Capivara National Park (PNSC) and surrounding areas in order to analise the diversity of mammal intestinal helminths. This work used the helminthological fauna findings of wild and domestic mammals, to consider a possible helminth flux between these two host groups using Unweighted Pair Group Method with Arithmetic Mean (UPGMA) of the hosts based on helminthological fauna composition. The results indicate that the region of the PNSC still maintains environmental conditions that still keep wild mammal helminthological fauna composition different from the one found for domestic mammals.


Assuntos
Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Biodiversidade , Helmintos/classificação , Helmintos/isolamento & purificação , Animais , Brasil , Fezes/parasitologia
7.
Rev. bras. parasitol. vet ; 18(supl.1): 19-28, out.-dez. 2009. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-624824

RESUMO

Estudos sobre biodiversidade permitem avaliações ecossistêmicas e monitoramentos de impactos e mudanças ambientais. A diversidade parasitária pode refletir o processo coevolutivo entre parasitos e hospedeiros, e mudanças ambientais que permitem a perda, ganho ou a manutenção das espécies nesse processo. O presente trabalho utilizou espécies/morfotipos de ovos de helmintos encontrados em fezes de sete mamíferos silvestres (os grupos Dasypodidae e grandes felinos, e as espécies: Tamandua tetradactyla, Cebus apella, Alouatta caraya, Cerdocyon thous, Pecari tajacu) e dois domésticos (Canis familiaris e Sus scrofa), que cohabitam o Parque Nacional Serra da Capivara (PNSC) e seu entorno, para analisar a diversidade dos helmintos intestinais desses mamíferos. Neste trabalho, utilizou-se achados da fauna helmintológica de mamíferos silvestres e domésticos, para avaliar um possível fluxo de helmintos entre estes dois grupos hospedeiros usando Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dos hospedeiros com base na composição de suas faunas helmintológicas. Os resultados indicam que a região do PNSC, ainda mantém condições ambientais que ainda propiciam a manutenção da composição da fauna de helmintos de mamíferos silvestres, diferente da encontrada nos animais domésticos.


Biodiversity studies allow ecosystem assessment and monitoring of environmental changes and impacts. Parasite diversity could reflect the host/ parasite coevolutionary process and the environment changes that permit the loss, gain or maintenance of species. This survey used species/morphotypes of helminths eggs found in feces from seven wild mammal species (the groups Dasypodidae and Large Cats, and Tamandua tetradactyla, Cebus apella, Alouatta caraya, Cerdocyon thous, Pecari tajacu) and from two domestic species (Canis familiaris and Sus scrofa), which occur within the Serra da Capivara National Park (PNSC) and surrounding areas in order to analise the diversity of mammal intestinal helminths. This work used the helminthological fauna findings of wild and domestic mammals, to consider a possible helminth flux between these two host groups using Unweighted Pair Group Method with Arithmetic Mean (UPGMA) of the hosts based on helminthological fauna composition. The results indicate that the region of the PNSC still maintains environmental conditions that still keep wild mammal helminthological fauna composition different from the one found for domestic mammals.


Assuntos
Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Biodiversidade , Helmintos/classificação , Helmintos/isolamento & purificação , Brasil , Fezes/parasitologia
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