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1.
J Wildl Dis ; 57(2): 443-446, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33822143

RESUMO

We evaluated the presence of antibodies for rabies virus in 177 serum samples from 125 wild lowland tapirs (Tapirus terrestris) from three different Brazilian biomes. The rapid fluorescent focus inhibition test was performed. No antibody titers suggesting the circulation of the rabies virus in tapir habitat were detected.

2.
Ticks Tick Borne Dis ; 12(3): 101648, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33508536

RESUMO

This study evaluated ticks and rickettsial exposure in 220 free-ranging lowland tapirs, Tapirus terrestris, from 2006 to 2018 in selected areas of three major biomes of Brazil - Atlantic Forest, Pantanal, and Cerrado. Overall, a total of 5970 tick specimens representing the following nine species were collected from tapirs: Amblyomma brasiliense, Amblyomma coelebs, Amblyomma dubitatum, Amblyomma ovale, Amblyomma parvum, Amblyomma sculptum, Amblyomma triste, Haemaphysalis juxtakochi, and Rhipicephalus microplus. Amblyomma sculptum was the most prevalent and abundant tick species in all three biomes; however, mean intensity values for A. sculptum were significantly lower in Atlantic Forest than in the Pantanal or Cerrado, and at the same time, statistically similar among tapirs from Pantanal and Cerrado. Contrastingly, mean intensity values for A. coelebs were significantly higher in the Atlantic Forest than in the other biomes. The remaining tick species were collected in lower numbers, or were exclusive for one biome, e.g., A. brasiliense and H. juxtakochi only in the Atlantic Forest. A total of 177 blood sera (123 individuals plus 54 recaptures) were collected from tapirs and tested for the presence of reactive antibodies to six Rickettsia species by immunofluorescence assay. Overall, 69% (9/13), 49% (62/126), and 66% (25/38) tapir sera from Atlantic Forest, Pantanal and Cerrado, respectively, were seroreactive to at least one Rickettsia species, with no significant difference between the three areas. Although many tapir sera reacted simultaneously to ≥2 Rickettsia species, Rickettsia parkeri elicited highest % seroprevalence and endpoint titers, and was incriminated as the possible agent involved in a homologous reaction in tapirs from the three biomes, where A. ovale was previously found infected by R. parkeri. In fact, seroconversion to R. parkeri was demonstrated in five tapirs that were captured at least twice during the study. This study demonstrated that tapirs were found to be constantly infested by several tick species in the Atlantic Forest, Pantanal and Cerrado biomes; however, the richness of tick infestations was concordant to the tick species known to be established in each biome. Under natural conditions, lowland tapirs were shown to be exposed to tick-borne spotted fever group rickettsiae.

3.
J Wildl Dis ; 56(1): 34-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31526278

RESUMO

Over 2 yr, we assessed the health of 35 lowland tapirs (Tapirus terrestris) in the Brazilian Cerrado (CE) biome, an area that is highly affected by human activities. This involved physical examinations, hematology and blood biochemistry, urinalysis, fecal parasitologic evaluation, microbial profiling of anatomic cavities and lesions, and serologic surveys for evidence of infectious agents. Research methods closely resembled those used in previous tapir health assessments in the Atlantic Forest (AF) and Pantanal (PA) biomes, allowing for a comparison among the three populations. Although not reaching statistical significance (P>0.05), tapirs from the CE exhibited poorer body and skin condition as compared to animals from the AF and PA. Furthermore, there were higher prevalences of dental problems and traumatic lesions as compared to those from the AF and PA. Eight of the 12 hematologic parameters evaluated and 17 of the 30 biochemical parameters differed significantly (P<0.05) between the tapirs from CE and those from the AF and PA. We isolated 24 different microbiologic strains from swabs of anatomic cavities and dermal lesions, of which five taxa had not previously been found in the AF or PA. We detected serum antibodies to Leptospira interrogans, bluetongue virus, and porcine parvovirus. Overall, our results suggested that tapirs from the CE exhibited more health abnormalities than tapirs in the AF and PA, possibly due to a greater exposure to environmental disturbances in the area.

4.
Parasit Vectors ; 12(1): 473, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604471

RESUMO

BACKGROUND: A considerable amount of evidence has favored ecological host-fitting, rather than coevolution, as the main mechanism responsible for trypanosome divergence. Nevertheless, beyond the study of human pathogenic trypanosomes, the genetic basis of host specificity among trypanosomes isolated from forest-inhabiting hosts remains largely unknown. METHODS: To test possible scenarios on ecological host-fitting and coevolution, we combined a host capture recapture strategy with parasite genetic data and studied the genetic variation, population dynamics and phylogenetic relationships of Trypanosoma terrestris, a recently described trypanosome species isolated from lowland tapirs in the Brazilian Pantanal and Atlantic Forest biomes. RESULTS: We made inferences of T. terrestris population structure at three possible sources of genetic variation: geography, tapir hosts and 'putative' vectors. We found evidence of a bottleneck affecting the contemporary patterns of parasite genetic structure, resulting in little genetic diversity and no evidence of genetic structure among hosts or biomes. Despite this, a strongly divergent haplotype was recorded at a microgeographical scale in the landscape of Nhecolândia in the Pantanal. However, although tapirs are promoting the dispersion of the parasites through the landscape, neither geographical barriers nor tapir hosts were involved in the isolation of this haplotype. Taken together, these findings suggest that either host-switching promoted by putative vectors or declining tapir population densities are influencing the current parasite population dynamics and genetic structure. Similarly, phylogenetic analyses revealed that T. terrestris is strongly linked to the evolutionary history of its perissodactyl hosts, suggesting a coevolving scenario between Perissodactyla and their trypanosomes. Additionally, T. terrestris and T. grayi are closely related, further indicating that host-switching is a common feature promoting trypanosome evolution. CONCLUSIONS: This study provides two lines of evidence, both micro- and macroevolutionary, suggesting that both host-switching by ecological fitting and coevolution are two important and non-mutually-exclusive processes driving the evolution of trypanosomes. In line with other parasite systems, our results support that even in the face of host specialization and coevolution, host-switching may be common and is an important determinant of parasite diversification.


Assuntos
Perissodáctilos/parasitologia , Trypanosoma/classificação , Jacarés e Crocodilos/parasitologia , Animais , Teorema de Bayes , Coevolução Biológica , Análise por Conglomerados , Fenômenos Ecológicos e Ambientais , Ecossistema , Variação Genética , Genética Populacional , Interações Hospedeiro-Parasita , Filogenia , Dinâmica Populacional , Trypanosoma/genética , Trypanosoma/crescimento & desenvolvimento
5.
J Environ Manage ; 248: 109320, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376609

RESUMO

We modelled the spatiotemporal patterns of road mortality for seven medium-large mammals, using a roadkill dataset from Mato Grosso do Sul, Brazil (800 km of roads surveyed every two weeks, for two years). We related roadkill presence-absence along the road sections (1000 m) and across the survey dates with a collection of environmental variables, including land cover, forest cover, distance to rivers, temperature, precipitation and vegetation productivity. We further included two variables aiming to reflect the intrinsic spatial and temporal roadkill risk. Environmental variables were obtained through remote sensing and weather stations, allowing the estimate of the roadkill risk for the entire surveyed roads and survey periods. Overall, the models could explain a small fraction of the spatiotemporal patterns of roadkills (<0.23), probably due to species being habitat generalists, but still had reasonable discrimination power (AUC averaging 0.70 ±â€¯0.07). The intrinsic spatial and temporal roadkill risk were the most important variables, followed by land cover, climate and NDVI. We show that identifying spatiotemporal roadkill patterns may provide valuable information to define specific management actions focused on road sections and time periods, in complement to permanent road mitigation measures. Our approach thus offers a new insight into the understanding of road effects and how to plan and strategize monitoring and mitigation.


Assuntos
Ecossistema , Mamíferos , Animais , Brasil , Florestas , Rios
6.
J Wildl Dis ; 50(4): 817-28, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25105810

RESUMO

Abstract The lowland tapir (Tapirus terrestris) is found in South America and is listed as Vulnerable to Extinction by the International Union for Conservation of Nature, Red List of Threatened Species. Health issues, particularly infectious diseases, are potential threats for the species. Health information from 65 wild tapirs from two Brazilian biomes, Atlantic Forest (AF) and Pantanal (PA), were collected during a long-term study (1996-2012). The study included physic, hematologic and biochemical evaluations, microbiologic cultures, urinalysis, and serologic analyses for antibodies against 13 infectious agents (viral and bacterial). The AF and PA tapirs were significantly different for several hematologic and biochemical parameters. Ten bacteria taxa were identified in the AF and 26 in the PA. Antibodies against five viruses were detected: Bluetongue virus, eastern equine encephalitis virus, western equine encephalitis virus, infectious bovine rhinotracheitis virus, and porcine parvovirus. A high prevalence of exposure to Leptospira interrogans (10 serovars: Autumnalis, Bratislava, Canicola, Copenhageni, Grippotyphosa, Hardjo, Hebdomadis, Icterohaemorrhagiae, Pomona, and Pyrogenes) was detected in both the AF and PA sites. A greater diversity of serovars and higher antibody titers were found in the PA. Statistically significant differences between sites were found for L. interrogans, equine encephalitis virus, and porcine parvovirus. Based on physical evaluations, both AF and PA populations were healthy. The differences in the overall health profile of the AF and PA tapir populations appear to be associated with environmental factors and infectious diseases ecology. The extensive datasets on hematology, biochemistry, urinalysis, and microbiology results from this paper can be used as reference values for wild tapirs.


Assuntos
Infecções Bacterianas/veterinária , Perissodáctilos , Viroses/veterinária , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Infecções Bacterianas/sangue , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Brasil/epidemiologia , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Viroses/sangue , Viroses/epidemiologia , Viroses/virologia
7.
Integr Zool ; 7(4): 331-345, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23253365

RESUMO

Tapirs have unique nutritional needs, as well as anatomical, physiological, behavioral and ecological adaptations that must be considered when managing their health, both in the wild and in captivity. Information about how tapirs live in their natural habitats can provide crucial knowledge to prevent many of the health problems found in captivity such as infectious and parasitic diseases, reproductive issues and nutritional and behavioral disorders. Likewise, proper management in captivity can significantly contribute to in situ conservation programs. Conservation medicine is a science created to address the global health crisis that jeopardizes biodiversity causing imbalances among ecosystem, human, animal and vegetal health. In this context, common threats to tapir health and conservation, such as isolated and small populations surrounded by human activity, chemical pollution, domestic animals and their pathogenic agents, need to be better understood. This manuscript provides information about the health of tapirs both in captivity and in the wild and aims to encourage tapir conservationists worldwide to gather information about pathogen and disease dynamics and manifestation, as well as implications for tapir conservation.


Assuntos
Criação de Animais Domésticos/métodos , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais de Zoológico , Conservação dos Recursos Naturais/métodos , Nível de Saúde , Perissodáctilos/fisiologia , Medicina Veterinária/métodos , Animais
8.
Integr Zool ; 7(4): 346-355, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23253366

RESUMO

In this manuscript, as a starting point, the ancient and current distribution of the genus Tapirus are summarized, from its origins, apparently in Europe, to current ranges. Subsequently, original and current tapir habitats are described, as well as changes in ancient habitats. As the manuscript goes on, we examine the ways in which tapir species interact with their habitats and the main aspects of habitat use, spatial ecology and adaptability. Having reviewed the historic and current distribution of tapirs, as well as their use and selection of habitats, we introduce the concept of adaptability, considering that some of the tapir physiological characteristics and behavioral strategies can reduce the negative impact of habitat alteration and climate change. Finally, we provide recommendations for future research priorities. The conservation community is still missing important pieces of information for the effective conservation of tapirs and their remaining habitats in Central and South America and Southeast Asia. Reconstructing how tapir species reached their current distribution ranges, interpreting how they interact with their habitats and gathering information regarding the strategies they use to cope with habitat changes will increase our understanding about these animals and contribute to the development of conservation strategies.


Assuntos
Adaptação Fisiológica/fisiologia , Comportamento Animal/fisiologia , Evolução Biológica , Mudança Climática , Conservação dos Recursos Naturais/métodos , Demografia , Ecossistema , Perissodáctilos/fisiologia , Animais
9.
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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