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Microbiome studies targeting hypervariable regions of the 16S rRNA gene are suitable for understanding interactions between animals and their associated bacteria. While many studies focus on the gut microbiome, assessments of blood microbiota remain scarce despite the prevalence of blood-borne pathogens in vertebrates. This study aimed to investigate the bacterial community in blood samples from 79 living and 7 road-killed lowland tapirs (Tapirus terrestris), a vulnerable species, sampled in two biomes in midwestern Brazil: Pantanal and Cerrado. Animals were categorized by condition (living or road-killed), sex, age, and biome. V3–V4 16S rRNA fragments were obtained from 86 blood samples and 4 negative controls. After filtering contaminants, 13,742,198 sequences representing 2146 ASVs were analyzed. Alpha diversity significantly differed by condition, while beta diversity differed by condition, site, and age (adults vs. sub-adults). For living animals (79/86 samples), alpha diversity showed no significant differences, but beta diversity differed by age. Different vector-borne bacterial pathogens, including Anaplasmataceae, Bartonella, and Borrelia spp., were detected. Additionally, evidence of transient translocation of microbial communities from other body regions to the bloodstream was observed. Amplification of bacterial 16S rRNA from blood samples of wild T. terrestris provided novel information about the diversity of blood-borne microbiota of lowland tapirs, members of a poorly studied mammalian family. Next-generation sequencing proved to be a valuable tool for screening potential vector-borne pathogens in this host.

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IntroductionUnderstanding human-wildlife interactions is critical to overcoming the socio-environmental crises we face worldwide. Among these interactions, poaching and hunting, human-wildlife conflict, and transmission of zoonotic diseases are major causes of biodiversity loss and detrimental to human well-being. Therefore, this study aimed to analyze wildlife poaching, feral pig hunting, human-wildlife conflict, and health issues in a region of the Brazilian Cerrado, in the state of Mato Grosso do Sul. The study also focused on the lowland tapir (Tapirus terrestris), a poached species listed as vulnerable to extinction.MethodsFrom October 2016 to September 2017, we conducted face-to-face semi-structured interviews with 51 local people from nine stakeholder groups. Interview answers and additional information compiled during the study were evaluated using coding, narrative, and co-occurrence analyses.Results and discussionWe found that the main human-wildlife conflict in the region involves feral pigs, and hunting is practiced as a population control strategy. The lowland tapir is not considered a conflictual species, as it is beloved by most people. However, tapirs are still poached, although less so than in the past, mainly for cultural reasons. Culture was the main motivation behind wildlife poaching in general. We identified 28 species and five taxa currently poached in this Cerrado region, of which 11 are used for medical and aphrodisiac purposes. Historically, wildlife poaching was linked to poor livelihood conditions and lack of support from governmental institutions during the Agrarian Reform process, becoming a cultural habit over the years. Nevertheless, wildlife poaching is less frequent than in the past, and its main barriers are surveillance, poaching prohibition by landowners, and social norm. Therefore, promoting a change in the way people relate to nature, meeting socioeconomic needs, and increasing surveillance appear to be important conservation strategies. Although feral pig hunting may replace wildlife poaching, some hunters still poach wild species, especially peccaries. Hence, it is necessary to keep hunters under surveillance, raise awareness among them, and make them allies in conservation strategies. We found a worryingly low level of awareness about disease transmission risk through bushmeat manipulation and consumption, highlighting the importance of One Health approaches.

Tapirus terrestris is the largest South American land mammal, with an extensive historical distribution and capable of occupying diverse habitats, and yet its populations have declined across its range. In order to provide baseline data on the conservation status of tapirs in the Atlantic Forest, we conducted a long-term study in one landscape, visited 93 forests, and received 217 expert reports over the 15-year study. We estimate that 2,665–15,992 tapirs remain in 48 confirmed populations, occupying 26,654 km2 of forest or 1.78% of its original range in the biome. Historically, hunting and deforestation were the main causes of decline, but today population isolation is the principal long-term threat. Vortex models indicate that 31.3–68.8% and 70.8–93.8% of the populations are demographically and genetically non-viable over the next 100 years, respectively, and that only 3–14 populations are viable when considering both variables. Habitat use data indicate that tapirs are adaptable to disturbed and secondary forests and will use diverse tree plantations and agricultural lands but hunting and highways keep populations isolated. Reserve staff report tapirs as common/abundant at 62.2% of the sites, and populations as stable and growing in 60% and 36% of the sites, respectively, and there is ample habitat in the biome for a population expansion, but overcoming the causes of isolation will be necessary for this to occur. Lack of adequate funding for protecting reserves is a chronic threat throughout the biome, especially in federal and state/provincial reserves, and increased funding will be necessary to implement effective conservation plans.

O atropelamento de fauna silvestre em estradas é responsável pela perda direta de milhões de indivíduos anualmente no Brasil, sendo importante acessar, compreender e mitigar seus impactos. Apresentamos um diagnóstico sobre o atropelamento de mamíferos na bacia hidrográfica do alto Paraguai (BAP), com o objetivo de acessar o atual estado de conhecimento, identificar lacunas e propor medidas de conservação e mitigação. Os dados foram coletados através de uma revisão sistemática da literatura científica, posteriormente caracterizados de acordo com tipo de estudo, localidade na BAP, riqueza e status de conservação de espécies e taxas de atropelamento. Identificamos 15 estudos que realizaram monitoramentos sistemáticos de atropelamento, a maioria em estradas do Mato Grosso do Sul. Entre eles, 93% dos monitoramentos foram realizados por carro, com uma duração média de 14 meses. Compilamos 5.241 indivíduos atropelados, distribuídos em dez ordens e 47 espécies, sendo a ordem Carnivora a mais representativa. Doze espécies apresentaram o status de ameaçada de extinção em nível nacional; destas, o tamanduá-bandeira (Myrmecophaga tridactyla) possui as maiores médias de taxas de atropelamento. Nosso diagnóstico se mostrou importante para identificar espécies vulneráveis aos efeitos dos atropelamentos, nortear novas pesquisas e auxiliar nas estratégias em políticas públicas e mitigação de impactos.

Wildlife road mortality is a worldwide problem. In tropical developing countries, it is urgent to implement and test mitigation measures to reduce wildlife-vehicle collisions, especially because financial resources are limited and alternatives should be considered such as retrofitting of existing underpasses. We assessed herein the use of 12 unfenced crossing structures, including drainage culverts and cattle boxes, by medium and large mammals along a highway in the Brazilian Cerrado. Underpass usage was monitored for 3682 trapping nights from September 2017 to May 2018. We recorded 20 species of medium and large wild mammals in a total of 4212 events. The most frequent mammals were lowland tapirs (Tapirus terrestris, n = 1154), followed by capybaras (Hydrochoerus hydrochaeris, n = 910), and crab-eating foxes (Cerdocyon thous, n = 271). Underpass usage did not differ between drainage culverts and cattle boxes, but species composition differed among the structures, suggesting that terrestrial mammals prefer cattle boxes while some semiaquatic species used only culverts. We identified 28 different individual tapirs using the underpasses and we estimated over 180 tons of tapir biomass crossing under the highway. Tapir underpass usage did not differ between cattle boxes and culverts, but it was negatively associated with the presence of pasture area around the structures. Our study suggests that, although underpasses show high mammal usage suggesting a satisfactory level of connectivity, combining this method with fencing would be critical to substantially decrease wildlife road mortality and increase human safety.

Abstract 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.

The low-land tapir (Tapirus terrestris) is the largest wild terrestrial mammal found in Brazil. Although T. terrestris has been already reported as a host of hemoparasites, the occurrence and genetic identity of Piroplasmida agents in this species is still cloudy. Although it is reported that Theileria equi, an endemic equid-infective agent in Brazil, is occurring in lowland tapirs, these reports are probably misconceived diagnoses since they are solely based on small fragments of 18S rRNA that may not achieve accurate topologies on phylogenetic analyses. The present study aimed to detect and investigate the identity of Theileria spp. in tapirs from Pantanal and Cerrado biomes. Blood-DNA samples from tapirs were screened for a partial (~800 bp) 18S rRNA gene fragment from Piroplasmida and 64 (64/122; 52.46% CI: 43.66–61.11%) presented bands of expected size. Samples were submitted to different protocols for molecular characterization, including near-full length 18S rRNA gene (~1500 bp), and the ema-1 gene from T. equi. Eight sequences were obtained for extended fragments (1182–1473 bp) from the 18S rRNA gene. Moreover, three sequences from partial cox-1 and five from partial hsp70 gene were obtained. None of the samples presented amplifications for the ema-1 gene. Phylogenetic and distance analyses from the 18S rRNA sequences obtained demonstrated a clear separation from tapirs’ Theileria spp. and T. equi. Phylogenetic analyses of cox-1 and hsp70 sequences obtained herein also showed a unique clade formed by tapir’s Theileria spp. Theileria terrestris sp. nov. is positioned apart from all other Theileria species in 18S rRNA, cox-1, and hps70 phylogenetic analyses. This novel proposed species represents a new Piroplasmida clade, yet to be characterized regarding biological features, vectors involved in the transmission cycles, additional vertebrate hosts, and pathogenicity.

The lowland tapir (Tapirus terrestris) is the largest land mammal in Brazil and classified as a vulnerable species, according to the assessment of the risk of extinction. The present study aimed at investigating the occurrence and genetic diversity of hemoplasmas in free-ranging T. terrestris from the Brazilian Pantanal and Cerrado biomes. Blood samples were collected from 94 living and eight road-killed tapirs, totalizing 125 samples Conventional PCR targeting four different genes (16S rRNA, 23S rRNA, RNAse P, and dnaK) were performed, and the obtained sequences were submitted for phylogenetic, genotype diversity, and distance analyses. The association between hemoplasma positivity and possible risk variables (age, gender, and origin) was assessed. Out of 122 analyzed samples, 41 (41/122; 33.61% CI: 25.84–42.38%) were positive in the 16S rRNA-based PCR assay for hemoplasmas. Positivity for hemoplasmas did not differ between tapirs’ gender and age. Tapirs from Pantanal were 5.64 times more likely to present positive results for hemoplasmas when compared to tapirs sampled in Cerrado. BLASTn, phylogenetic, genotype diversity, and distance analyses performed herein showed that the sampled lowland tapirs might be infected by two genetically distinct hemoplasmas, namely ‘Candidatus Mycoplasma haematoterrestris’ and ‘Candidatus Mycoplasma haematotapirus’. While the former was positioned into “Mycoplasma haemofelis group” and closely related to ‘Candidatus Mycoplasma haematoparvum, the latter was positioned into “Mycoplasma suis group” and closely related to ‘Candidatus Mycoplasma haematobos’. The impact of both putative novel species on tapir health status should be investigated.