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1.
Am J Primatol ; 86(7): e23635, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38738522

RESUMO

The golden lion tamarin (GLT) is an Endangered primate endemic to Brazil's lowland Atlantic Forest. After centuries of deforestation and capture for the pet trade, only a few hundred individuals survived, all in isolated forest fragments 85 km from Rio de Janeiro city. Intensive conservation actions, including reintroduction of zoo-born tamarins, increased numbers to about 3700 in 2014. The most severe yellow fever epidemic/epizootic in Brazil in 80 years reduced two of the largest GLT populations by over 90%. Herein we report the results of a 2023 survey of GLTs designed to examine the dynamics of population recovery following yellow fever. Results indicate that populations hard hit by yellow fever are recovering due in part to immigration from adjacent forest fragments. No local extirpations were observed. About 4800 GLTs live in the survey area. This represents a 31% increase since the baseline survey completed in 2014. Two factors explain most of the increase: four large areas that had no GLTs or very low-density populations in 2014 are now at moderate density (three areas) or low density (one area), explaining 71% of overall increase since 2014. Increase in forest area within our survey area may explain up to 16% of the increase in GLT numbers since 2014. Results of computer simulations suggest that strengthening forest connectivity will facilitate metapopulation resilience in the face of mortality factors such as yellow fever.


Assuntos
Leontopithecus , Dinâmica Populacional , Febre Amarela , Animais , Febre Amarela/epidemiologia , Brasil/epidemiologia , Doenças dos Macacos/epidemiologia , Espécies em Perigo de Extinção , Conservação dos Recursos Naturais , Feminino , Masculino
2.
Am J Primatol ; 86(5): e23606, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38340360

RESUMO

Many animal species depend on sound to communicate with conspecifics. However, human-generated (anthropogenic) noise may mask acoustic signals and so disrupt behavior. Animals may use various strategies to circumvent this, including shifts in the timing of vocal activity and changes to the acoustic parameters of their calls. We tested whether pied tamarins (Saguinus bicolor) adjust their vocal behavior in response to city noise. We predicted that both the probability of occurrence and the number of long calls would increase in response to anthropogenic noise and that pied tamarins would temporally shift their vocal activity to avoid noisier periods. At a finer scale, we anticipated that the temporal parameters of tamarin calls (e.g., call duration and syllable repetition rate) would increase with noise amplitude. We collected information on the acoustic environment and the emission of long calls in nine wild pied tamarin groups in Manaus, Brazil. We found that the probability of long-call occurrence increased with higher levels of anthropogenic noise, though the number of long calls did not. The number of long calls was related to the time of day and the distance from home range borders-a proxy for the distance to neighboring groups. Neither long-call occurrence nor call rate was related to noise levels at different times of day. We found that pied tamarins decreased their syllable repetition rate in response to anthropogenic noise. Long calls are important for group cohesion and intergroup communication. Thus, it is possible that the tamarins emit one long call with lower syllable repetition, which might facilitate signal reception. The occurrence and quantity of pied tamarin' long calls, as well as their acoustic proprieties, seem to be governed by anthropogenic noise, time of the day, and social mechanisms such as proximity to neighboring groups.


Assuntos
Leontopithecus , Vocalização Animal , Humanos , Animais , Vocalização Animal/fisiologia , Saguinus/fisiologia , Ruído
3.
Am J Primatol ; 86(4): e23588, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38143424

RESUMO

The golden-headed lion tamarin (Leontopithecus chrysomelas) is an endangered primate that occurs exclusively in the Atlantic Forest of southern Bahia, Brazil. Its geographic range has been severely reduced by deforestation and its populations are restricted to a human-modified landscape consisting primarily of Atlantic forest fragments and shade cacao (Theobroma cacao) agroforestry, locally known as cabrucas. In the last 30 years, there has been a 42% reduction in the geographic range and a 60% reduction in the population size of L. chrysomelas, with only 8% of its habitat represented by protected areas. Thus, we investigated the occurrence of L. chrysomelas in forest fragments and cabrucas based on interviews and using playback census, and evaluated the influence of landscape attributes on its occurrence. The occurrence was measured using a Generalized Linear Model using a set of 12 predictor variables, including fragment size and elevation. L. chrysomelas inhabited 186 (38%) of the 495 forest fragments and cabrucas. Most inhabited habitat patches (n = 169, 91%) are in the eastern portion (ca. 70 km wide region from the Atlantic coast to inland) of its geographic range. The remaining (n = 17, 9%) are in the western portion of the distribution, between 70 and 150 km from the Atlantic coast. Our models indicate a higher occurrence of L. chrysomelas in the eastern portion of its geographic range, where the landscape exhibits lower land cover diversity, greater functional connectivity, lower altitudes (<400 m), and is primarily composed of forest fragments and cabrucas with a higher core percentage. In contrast, we observed a lower occurrence of L. chrysomelas in the western portion, where the landscape is more diverse and heterogeneous due to anthropogenic activities, such as agriculture and livestock. We urge the establishment of ecological corridors via reforestation of degraded areas in the western portion of the range. This increase in habitat availability and suitability in the west together with the protection of the forests and cabrucas in the east would increase our chances of saving L. chrysomelas from extinction.


Assuntos
Leontopithecus , Humanos , Animais , Brasil/epidemiologia , Florestas , Ecossistema
4.
PLoS One ; 18(8): e0288097, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37531319

RESUMO

Leontopithecus chrysomelas, the Golden-headed Lion Tamarin (GHLT), is an endangered and endemic Neotropical primate from the Atlantic Forest of Brazil that has suffered a reduction of its habitat and population size in the wild. Ex situ populations have been established as a relevant alternative to safeguard the species and retain its genetic diversity and evolutionary potential. This study evaluated the genetic diversity and structure of the two main Brazilian captive populations of GHLT, which have been under human care at the Primatology Center of Rio de Janeiro (CPRJ) and the Zoological Park Foundation of São Paulo (FPZSP). Our results revealed levels of genetic diversity overall comparable to those observed for other Leontopithecus species and for ex situ and in situ populations of GHLT previously studied. Bayesian and principal coordinate analyses showed a moderate differentiation between CPRJ and FPZSP populations. Both populations presented observed heterozygosity values higher than expected heterozygosity values for most of the microsatellites used in this study, suggesting that the management has been efficient in avoiding an increase in homozygosity. However, simulations point to a significant loss of genetic diversity in the next 100 years, mainly in the FPZSP population. Such data are relevant for further decision-making on the metapopulation management of L. chrysomelas in captive conditions and for integrating in situ and ex situ conservation plans.


Assuntos
Leontopithecus , Animais , Humanos , Leontopithecus/genética , Teorema de Bayes , Brasil/epidemiologia , Variação Genética , Espécies em Perigo de Extinção
5.
Am J Primatol ; 85(7): e23503, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37157182

RESUMO

Identifying the factors swaying physiological stress levels in wild animals can help depict how they cope with environmental and social stressors, shedding light on their feeding ecology, behavioral plasticity, and adaptability. Here, we used noninvasive methods to explore the link between glucocorticoid levels and behavior in an endangered neotropical primate facing habitat fragmentation pressure, the black lion tamarin (Leontopithecus chrysopygus). We investigated monthly and day-to-day glucocorticoid variations independently to attempt to disentangle the complex nature of the adrenocortical activity. Between May 2019 to March 2020, we followed two groups of black lion tamarins in two different areas, a continuous forest and a small fragment, and gathered behavioral data (over 95 days in total; 8.6 ± 3.9 days/month) and fecal samples (Nsamples = 468; 4.93 ± 3.5 samples/day) simultaneously. Preliminary analyses enabled us to identify circadian variations linked to the biological rhythm, which were taken into account in subsequent models. Monthly analyses revealed that black lion tamarin fecal glucocorticoid metabolite levels vary according to changes in activity budget associated with the fruit consumption, movement, and resting time of the groups. At a day-to-day level, while intergroup encounters led to increases in fecal glucocorticoid metabolite concentrations, we found that changes in food intake or activity level did not trigger physiological stress responses. These findings suggest that diet and ranging patterns, driven by food availability and distribution, influence physiological stress at a seasonal scale, while acute stressors such as interspecific competition trigger short-term stress responses. Exploring fecal glucocorticoid metabolite variations over different timescales can help uncover the predictive and reactive facets of physiological stress in wild species. Moreover, having a comprehensive understanding of the physiological state of species is a valuable conservation tool for evaluating how they cope in changing environments.


Assuntos
Glucocorticoides , Leontopithecus , Animais , Glucocorticoides/análise , Primatas , Animais Selvagens , Ecossistema
6.
J Med Primatol ; 52(1): 17-23, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36028986

RESUMO

BACKGROUND: Cholelithiasis is a digestive system disorder of multifactorial origin that occurs due to stones formed in the gallbladder. This study aimed at investigating by abdominal ultrasound examination the prevalence of cholelithiasis in lion tamarins kept under human care. METHODS: Thirty lion tamarins from five Brazilian zoos, including 17 golden lion tamarins and 13 golden-headed lion tamarins, were evaluated. RESULTS: Considering all lion tamarins, the overall frequency of cholelithiasis was 53.3% (16/30). There were no significant differences between species and sex. Cholelithiasis was predominant (75.0%) in lion tamarins older than 5 years. Septate gallbladder was observed in 86.6% (26/30) of the lion tamarins. Of these, 53.8% (14/26) had gallstones. Biochemical analysis revealed a moderate positive correlation between gamma-glutamyl transferase and the number of gallstones. CONCLUSIONS: Asymptomatic cholelithiasis is frequent in lion tamarins kept under human care. Therefore, systematic monitoring through ultrasound should be part of the preventive care of these animals.


Assuntos
Cálculos Biliares , Leontopithecus , Humanos , Animais , Prevalência , Brasil/epidemiologia
7.
Am J Primatol ; 85(1): e23454, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36415048

RESUMO

Information about species distribution is important for conservation but the monitoring of populations can demand a high sampling effort with traditional methods (e.g., line transects, sound playback) that are poorly efficient for cryptic primates, such as the black lion tamarin (Leontopithecus chrysopygus). Here we investigated the effectiveness of passive acoustic monitoring (PAM) as an alternative method to identify the presence of vocalizing lion tamarins in the wild. We aimed to: (1) determine the maximum distance at which autonomous recorders (Song Meter 3) and Raven Pro acoustic software can respectively detect and identify lion tamarin long calls emitted by two captive subjects (ex situ study); and (2) determine the sampling effort required to confirm the presence of the species in the wild (in situ study). In captive settings, we recorded lion tamarin long calls with one to two autonomous recorders operating at increasing distances from the animals' enclosure (8-202 m). In a 515 ha forest fragment, we deployed 12 recorders in a grid, 300 m apart from each other, within the estimated 100 ha home range of one group, and let them record for 10 consecutive days, totaling 985 h. In the ex situ study, hand-browsing of spectrograms yielded 298 long calls emitted from 8 to 194 m, and Raven's Template Detector identified 54.6% of them, also emitted from 8 to 194 m. In the in situ study, we manually counted 1115 long calls, and the Raven's Template Detector identified 44.75% of them. Furthermore, the presence of lion tamarins was confirmed within 1 day using four randomly sorted recorders, whereas 5 days on average were necessary with only one device. While specific protocols still need to be developed to determine primate population size using this technology, we concluded that PAM is a promising tool when considering long term costs and benefits.


Assuntos
Leontopithecus , Animais , Espécies em Perigo de Extinção , Primatas , Densidade Demográfica , Florestas
8.
Viruses ; 14(10)2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36298786

RESUMO

Beside humans, thousands of non-human primates (NHPs) died during the recent outbreak caused by the yellow fever virus (YFV) in Brazil. Vaccination of NHPs against YFV with the YF 17DD attenuated virus has emerged as a public health strategy, as it would reduce sylvatic transmission while also preserving endangered susceptible species. The hypothesis of establishing an uncontrolled transmission of this attenuated virus in nature was raised. We assessed vector competence of four sylvatic mosquito species, Haemagogus leucocelaenus, Haemagogus janthinomys/capricornii, Sabethes albiprivus, and Sabethes identicus, as well as the urban vector Aedes aegypti for YF 17DD attenuated vaccine virus when fed directly on eleven viremic lion tamarins or artificially challenged with the same virus. No infection was detected in 689 mosquitoes engorged on viremic lion tamarins whose viremia ranged from 1.05 × 103 to 6.61 × 103 FFU/mL, nor in those artificially taking ≤ 1 × 103 PFU/mL. Low viremia presented by YF 17DD-vaccinated New World NHPs combined with the low capacity and null dissemination ability in sylvatic and domestic mosquitoes of this attenuated virus suggest no risk of its transmission in nature. Thus, vaccination of captive and free-living NHPs against YFV is a safe public health strategy.


Assuntos
Aedes , Leontopithecus , Febre Amarela , Animais , Humanos , Vírus da Febre Amarela , Febre Amarela/prevenção & controle , Febre Amarela/veterinária , Febre Amarela/epidemiologia , Mosquitos Vetores , Viremia/prevenção & controle , Vacinas Atenuadas , Primatas
9.
J Med Primatol ; 51(6): 381-383, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35394073

RESUMO

Primary female reproductive neoplasms in Platyrrhines species are few reported. We present the gross, histological, and immunohistochemical findings of metastatic endometrioid carcinoma in the uterus, urinary bladder, jejunum, and rectum of a Leontopithecus sp. The neoplastic endometrial cells expressed strong cytoplasmic immunolabeling of cytokeratin 7.


Assuntos
Carcinoma Endometrioide , Neoplasias do Endométrio , Leontopithecus , Animais , Feminino , Carcinoma Endometrioide/veterinária , Carcinoma Endometrioide/patologia , Carcinoma Endometrioide/secundário , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/veterinária , Imuno-Histoquímica/veterinária , Útero/patologia
10.
Am J Primatol ; 84(4-5): e23370, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35294050

RESUMO

The black lion tamarin (Leontopithecus chrysopygus) is an endangered primate species, restricted to the Atlantic Forest fragments of São Paulo state, Brazil, with an estimated wild population of ~1600 individuals. Integrative studies between zoo (ex situ) and wild (in situ) animals are crucial to modern conservation programs. They can demonstrate a substantial impact with the One Health concept, an interdisciplinary research frontier regarding the relations between human, animal, and environmental health. Studies of wild populations of Leontopithecus spp. are scarce and should be encouraged to provide baseline information to develop preventive and curative medicine in zoos and other conservation programs. Studying these animals in the wild can offer important reference parameters for the species. Comparing bacterial communities between in situ and ex situ populations can help us understand both conditions and the dynamics of potentially pathogenic microorganisms. To increase our understanding of resident microorganisms among these groups, we collected oral and rectal samples from captive (zoo) and wild black lion tamarins. We employed a culture method for the identification of aerobic bacteria. Thirty-three specimens were sampled (24 zoo and 8 wild animals) and 18 bacterial genera were identified. We found primarily Gram-positive bacteria in wild animals, whereas in zoo animals, Gram-negative bacteria were dominant. Some of the bacterial species we identified are potentially pathogenic, whereas several others are being reported here for the first time in this host species. Our results reinforce the importance of integrative studies for the future management and conservation of this endangered primate species.


Assuntos
Leontopithecus/microbiologia , Microbiota , Boca/microbiologia , Reto/microbiologia , Animais , Animais Selvagens , Animais de Zoológico , Bactérias , Brasil , Espécies em Perigo de Extinção , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Saúde Única
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