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1.
Am J Primatol ; 82(12): e23202, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33040387

RESUMO

Species distributions are influenced by both climate conditions and landscape structure. Here we propose an integrated analysis of climatic and landscape niche-based models for a forest-dependent primate, the endangered black lion tamarin (Leontopithecus chrysopygus). We applied both climate and landscape variables to predict the distribution of this tamarin and used this information to prioritize strategic areas more accurately. We anticipated that this approach would be beneficial for the selection of pertinent conservation strategies for this flagship species. First, we built climate and landscape niche-based models separately, combining seven algorithms, to infer processes acting on the species distribution at different scales. Subsequently, we combined climate and landscape models using the EcoLand Analysis. Our results suggest that historic and current landscape fragmentation and modification had profoundly adverse effects on the distribution of the black lion tamarins. The models indicated just 2096 km2 (out of an original distribution of 92,239 km2 ) of suitable areas for both climate and landscape. Of this suitable area, the species is currently present in less than 40%, which represents less than 1% of its original distribution. Based on the combined map, we determined the western and southeast regions of the species range to be priority areas for its conservation. We identified areas with high climatic and high landscape suitability, which overlap with the remaining forest fragments in both regions, for habitat conservation and population management. We suggest that areas with high climatic but low landscape suitability should be prioritized for habitat management and restoration. Areas with high landscape suitability and low climatic suitability, such as the Paranapiacaba mountain range should be considered in light of projected climate change scenarios. Our case study illustrates that a combined approach of climatic and landscape niche-based modeling can be useful for establishing focused conservation measures that may increase the likelihood of success.


Assuntos
Clima , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Meio Ambiente , Leontopithecus , Animais , Modelos Biológicos
2.
Am J Primatol ; 79(10)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28902417

RESUMO

The DARC (Duffy antigen receptor for chemokines) gene encodes the DARC protein, which serves multiple roles in the immune system, as a binding site for the malarial parasites Plasmodium vivax and Plasmodium knowlesi, a promiscuous chemokine receptor and a blood group antigen. Variation in DARC may play particularly significant roles in innate immunity, immunotolerance and pathogen entry in callitrichines, such as the black lion tamarin (Leontopithecus chrysopygus). We compared amino acid sequences of DARC in the black lion tamarin (BLT) to non-human Haplorhine primates and Homo sapiens. Consistent with prior studies in other Haplorhines, we observed that the chemokine receptor experiences two opposing selection forces: (1) positive selection on the Plasmodium binding site and (2) purifying selection. We observed also that D21N, F22L, and V25L differentiated BLT from humans at a critical site for P. vivax and P. knowlesi binding. One amino acid residue, F22L, was subject to both positive selection and fixation in New World monkeys, suggesting a beneficial role as an adaptive barrier to Plasmodium entry. Unlike in humans, we observed no variation in DARC among BLTs, suggesting that the protein does not play a role in immunotolerance. In addition, lion tamarins differed from humans at the blood compatibility Fya /Fyb antigen-binding site 44, as well as at the putative destabilizing residues A61, T68, A187, and L215, further supporting a difference in the functional role of DARC in these primates compared with humans. Further research is needed to determine whether changes in the Plasmodium and Fya /Fyb antigen-binding sites disrupt DARC function in callitrichines.


Assuntos
Suscetibilidade a Doenças , Sistema do Grupo Sanguíneo Duffy , Leontopithecus , Animais , Quimiocinas , Humanos , Primatas , Receptores de Superfície Celular
3.
Braz. j. microbiol ; 45(4): 1531-1539, Oct.-Dec. 2014. ilus
Artigo em Inglês | LILACS | ID: lil-741310

RESUMO

Black lion tamarins (Leontopithecus chrysopygus) are endangered callithrichids. Their conservation may require future translocations or reintroductions; however these approaches involve risks of pathogen introduction in the environment and stress-related opportunistic infections in these animals. In order to screen for opportunistic and potential pathogenic bacterial and fungal microbiota, ten free-ranging and ten captive Black lion tamarins were studied and the results compared. Nasal, oral and rectal swabs were collected and cultured for aerobic and facultative anaerobic bacteria and fungi, and a total 203 bacterial and 84 fungal isolates were obtained. Overall, the most frequent organisms were Staphylococcus spp., Bacillus spp., Candida spp. and Aspergillus spp. Microbiota of free-ranging and captive animals were similar in composition. A number of potentially pathogenic organisms were identified, emphasizing the importance of microbiological screening in future translocation or reintroduction conservation management programs.


Assuntos
Animais , Bactérias/classificação , Fungos/classificação , Leontopithecus/microbiologia , Microbiota , Boca/microbiologia , Cavidade Nasal/microbiologia , Reto/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Técnicas Microbiológicas
4.
Braz J Microbiol ; 45(4): 1531-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25763064

RESUMO

Black lion tamarins (Leontopithecus chrysopygus) are endangered callithrichids. Their conservation may require future translocations or reintroductions; however these approaches involve risks of pathogen introduction in the environment and stress-related opportunistic infections in these animals. In order to screen for opportunistic and potential pathogenic bacterial and fungal microbiota, ten free-ranging and ten captive Black lion tamarins were studied and the results compared. Nasal, oral and rectal swabs were collected and cultured for aerobic and facultative anaerobic bacteria and fungi, and a total 203 bacterial and 84 fungal isolates were obtained. Overall, the most frequent organisms were Staphylococcus spp., Bacillus spp., Candida spp. and Aspergillus spp. Microbiota of free-ranging and captive animals were similar in composition. A number of potentially pathogenic organisms were identified, emphasizing the importance of microbiological screening in future translocation or reintroduction conservation management programs.


Assuntos
Bactérias/classificação , Fungos/classificação , Leontopithecus/microbiologia , Microbiota , Boca/microbiologia , Cavidade Nasal/microbiologia , Reto/microbiologia , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Técnicas Microbiológicas
5.
Braz. j. biol ; 61(3)Aug. 2001.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467547

RESUMO

Foraging behavior, seasonality and time-budgets in the Black Lion Tamarin (L. chrysopygus) was observed in the Caetetus Ecological Station, South-eastern Brazil, during 83 days between November 1988 to October 1990. For the full dry season we found that animal prey represented 11.2% of the black lion tamarin diet, while during the wet season they represented 1.9%. Foraging behavior made up 19.8% of their total activity in the dry season and only 12.8% in the wet season. These results point out that animal prey are relatively more important during the dry season, due to reduced availability of other resources, e.g. fruits, and that a greater foraging effort is required when a larger proportion of the diet is animal prey.


O comportamento de forrageio por presas, a sazonalidade e o orçamento temporal das atividades no mico-leão-preto (L. chrysopygus) foram observados na Estação Ecológica dos Caetetus, sudeste do Brasil, durante 83 dias, entre novembro de 1988 e outubro de 1990. Para toda a estação seca, observou-se que as presas animais representaram 11,2% da dieta do mico-leão-preto, enquanto na estação chuvosa elas foram responsáveis apenas por 1,9%. O comportamento de forrageio por presas compreendeu 19,8% de sua atividade total na estação seca e 12,8% na estação chuvosa. Esses resultados indicam que as presas animais são relativamente mais importantes durante a estação seca, devido à redução na disponibilidade de outros recursos, como frutos, e que o maior esforço de forrageio é exigido quando a maior proporção da dieta é composta por presa animal.

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