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The dietary ecology of a species can provide information on habitat requirements, food resources, and trophic interactions, important to guide conservation efforts of wildlife populations in endangered habitats. In this study, we investigated the dietary ecology of bearded capuchin monkeys (Sapajus libidinosus) in Brasilia National Park, in the endangered Cerrado biome of central Brazil. To obtain diet composition and evaluate the role of these primates as seed dispersers of local tree species, fecal sample collections and feeding observations were performed for a 7-month period. To determine whether seeds germinated better after passing through a primate gut, we conducted germination trials with (i) pulped seeds from trees, (ii) depulped seeds from trees, (iii) seeds from feces planted with feces, and (iv) seeds from feces planted without feces. During experimental procedures, 7308 seeds from 8 families and 10 species were planted. We found that S. libidinosus spent more time feeding on fruits than on any other food item and the diet consisted of 33 plant species from 21 families. However, 20% of their diet consisted of anthropic food. Most seeds planted with feces germinated faster compared to seeds in other experimental treatments, suggesting that passing through the gut and being deposited with fecal material is advantageous. The bearded capuchins also defecated many medium- (5 species) and large-sized (2 species) seeds that may be inaccessible to smaller arboreal frugivores. The results obtained emphasize the important role of bearded capuchins as seed dispersers for the maintenance and conservation of the endangered Cerrado biome.
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Cebinae , Dieta , Fezes , Dispersão de Sementes , Sementes , Animais , Dieta/veterinária , Brasil , Cebinae/fisiologia , Parques Recreativos , Comportamento Alimentar , Germinação , Masculino , Espécies em Perigo de Extinção , FemininoRESUMO
Introduction: Bearded capuchins display a wide variety of manipulatory skills and make routine use of tools in both captivity and the wild. The efficient handling of objects in this genus has led several investigators to assume near-human thumb movements, despite a lack of anatomical studies. Methods: Here, we performed an anatomical analysis of muscles and bones in the capuchin hand. Sapajus morphological traits were quantitatively compared with those of humans, chimpanzees, gorillas, and baboons. Results: The comparative analysis indicated that the Sapajus hand is more similar to that of baboons and least similar to that of humans according to the muscles, bones, and three-dimensional data. Furthermore, these findings suggest that bearded capuchins lack true thumb opponency. Regarding manipulatory skills, they display rather primitive hand traits, with limited resources for precision grasping using the opponens pollicis. Discussion: These findings suggest that bearded capuchins' complex use of tools depends more heavily on their high cognitive abilities than on a versatile hand apparatus. These findings offer crucial insights into the evolution of primate cognition.
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Glucocorticoids (GCs) are mammalian steroid hormones involved in a variety of physiological processes, including metabolism, the immune response, and cardiovascular functions. Due to their link to the physiological stress response, GC measurement is a valuable tool for conservation and welfare assessment in animal populations. GC levels can be measured from different matrices, such as urine and feces. Moreover, especially in captive settings, measuring GCs from saliva samples proved particularly useful as those samples can be collected non-invasively and easily from trained animals. Salivary GC levels can be measured using a variety of analytical methods, such as enzyme immunoassays. However, it is crucial to validate the analytical method for each specific application and species when using a new matrix. Using high-pressure liquid chromatography and a cortisol enzyme immunoassay, we show that the main glucocorticoids secreted in the saliva of squirrel monkeys and brown capuchin monkeys are cortisol and cortisone. Our biological validation found the expected salivary cortisol level to decline throughout the day. Our findings support the reliability of salivary cortisol measurements and their potential to be used as a valid tool in research and welfare assessment for these non-human primates.
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Capuchin monkeys have rich social relationships and from very young ages they participate in complex interactions with members of their group. Lipsmacking behaviour, which involves at least two individuals in socially mediated interactions, may tell about processes that maintain, accentuate or attenuate emotional exchanges in monkeys. Lipsmacking is a facial expression associated with the establishment and maintenance of affiliative interactions, following under the 'emotional regulation' umbrella, which accounts for the ability to manage behavioural responses. We investigated behaviours related to the emitter and to the receiver (infant) of lipsmacking to answer the question of how lipsmacking occurs. In capuchin monkeys, lipsmacking has been previously understood solely as a face-to-face interaction. Our data show that emitters are engaged with infants, looking longer towards their face and seeking eye contact during the display. However, receivers spend most of the time looking away from the emitter and stay in no contact for nearly half of the time. From naturalistic observations of wild infant capuchin monkeys from Brazil we found that lipsmacking is not restricted to mutual gaze, meaning there are other mechanisms in place than previously known. Our results open paths to new insights about the evolution of socio-emotional displays in primates.
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Bite force and gape are two important performance metrics of the feeding system, and these metrics are inversely related for a given muscle size because of fundamental constraints in sarcomere length-tension relationships. How these competing performance metrics change in developing primates is largely unknown. Here, we quantified in vivo bite forces and gapes across ontogeny and examined these data in relation to body mass and cranial measurements in captive tufted capuchins, Sapajus spp. Bite force and gape were also compared across geometric and mechanical properties of mechanically challenging foods to investigate relationships between bite force, gape and food accessibility (defined here as the ability to breach shelled nuts). Bite forces at a range of gapes and feeding behavioral data were collected from a cross-sectional ontogenetic series of 20 captive and semi-wild tufted capuchins at the Núcleo de Procriação de Macacos-Prego Research Center in Araçatuba, Brazil. These data were paired with body mass, photogrammetric measures of jaw length and facial width, and food geometric and material properties. Tufted capuchins with larger body masses had absolutely higher in vivo bite forces and gapes, and animals with wider faces had absolutely higher bite forces. Bite forces and gapes were significantly smaller in juveniles compared with subadults and adults. These are the first primate data to empirically demonstrate the gapes at which maximum active bite force is generated and to demonstrate relationships to food accessibility. These data advance our understanding of how primates meet the changing performance demands of the feeding system during development.
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Força de Mordida , Crânio , Animais , Estudos Transversais , Comportamento Alimentar/fisiologia , Sarcômeros , Fenômenos Biomecânicos , Arcada Osseodentária/fisiologiaRESUMO
Among vector-borne helminths, filarioids of the genus Dipetalonema (Spirurida: Onchocercidae) localize in several tissues and body cavities of several animal species, causing mild to moderate lesions. The pathological findings associated with Dipetalonema spp. infection in Neotropical monkeys from southern Brazil are herein described, along with a fatal case due to filarial polyserositis and entrapment of an intestinal segment. At necropsy, nematodes were observed in abdominal and thoracic cavities, or in the pericardium of 37 (31.3%) out of the 118 individuals examined (i.e., 35 Alouatta guariba clamitans and two Sapajus nigritus). In addition, at histology, 27.0% of positive animals presented microfilarie (inside blood vessels of lung, spleen, liver, and brain) and 8.1% presented adult nematodes in the heart, lung, and liver. In two cases, cross-sections of filarioids were associated with areas of epicardial thickening with intense fibrosis and pyogranulomatous inflammation in the brain, heart, liver, lungs, or spleen. The DNA fragment was amplify using the cox1 gene, sequenced and analyzed to identify the nematode species collected; presence of Wolbachia was assessed in the filarioids using the 16S rRNA gene. At BLAST analysis of the cox1 gene, 10 sequences showed 91.7% nucleotide identity with Dipetalonema gracile, and two with D. gracile (98.5%) and Dipetalonema graciliformis (98.3%). Phylogenetic analyses clustered sequences of the cox1 obtained in this study in two clades corresponding with the host species. Wolbachia sp. endosymbiont was detected in four samples. Data herein reported provide a description of pathological lesions associated with the infection by Dipetalonema spp., suggesting that they may cause disease in Neotropical monkeys. In addition, a better understanding of diversity and biology of Dipetalonema spp. in South America is needed to assess the impact they may cause in native non-human primates from Brazil.
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Infecções por Dipetalonema , Dipetalonema , Filarioidea , Nematoides , Espirurídios , Animais , Dipetalonema/genética , Espirurídios/genética , Brasil/epidemiologia , Haplorrinos/genética , Filogenia , RNA Ribossômico 16S/genética , Filarioidea/genética , Infecções por Dipetalonema/parasitologia , Nematoides/genéticaRESUMO
In primates, many species exhibit same-sex sexual behaviors (SSB), defined as "genital contact or genital manipulation between same-sex individuals." Several sociosexual functions have been proposed, including proceptivity enhancement, receptivity reduction, dominance assertion, practice for heterosexual copulation, tension regulation, reconciliation, and alliance formation. Capuchin monkeys are known for their rich and flexible sexual behavioral repertoire and elaborated courtships. At present, the few reports of SSB in capuchin monkeys (genera Sapajus and Cebus) focused on mounting. Here, we describe the case observed in a population of wild yellow-breasted capuchin monkeys (Sapajus xanthosternos) in which two young males, aged 5-6 years and 19 months, performed a 15-min uninterrupted sequence of courtship behaviors and mounting. Comparing with a previously established ethogram of 20 behaviors typical for heterosexual behavior of tufted capuchins, we show that these males performed 16 of them. Thus, SSBs are already present in the repertoire of young individuals and the practice may serve to create or strengthen bonds. Although same-sex mounting and genital inspection are common in capuchins' play and other social interactions, the almost entire array of courtship behaviors has never been observed in youngsters. Additionally, this example supports the notion that primate (homo)sexual behavior is not limited to genitalia and copulation, since the observed courtship included diverse behaviors different from genital contact. Thus, we propose a broader definition of sexual behavior.
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Corte , Minorias Sexuais e de Gênero , Animais , Masculino , Humanos , Cebus/fisiologia , Comportamento Sexual Animal/fisiologia , HomossexualidadeRESUMO
Terrestriality was an essential factor in human evolution. Hominins' extensive use of the ground allowed exploring a new range of environments and their objects, including new resources and potential tool raw materials. Capuchin monkeys are primarily arboreal primates but are also the most prolific tool users among platyrrhines, customarily using stone tools on the ground due to physical limitations and material availability. OBJECTIVES: Our goals were to (1) measure the terrestriality levels of a group of capuchin monkeys and (2) test the hypothesis that terrestriality has a positive effect on the stone tool use variability because the increased time on the ground would offer more opportunities to interact with the available stones, leading to more innovations of tool use behaviors. We predict a more diversified use of stone tools in the population with a higher degree of terrestriality. MATERIALS AND METHODS: This study was on a group of capuchin monkeys (Sapajus libidinosus) at Serra da Capivara National Park (SCNP), Brazil. Scan sampling was done for 23 months, recording the behavior and substrate used by the individuals. RESULTS: The ground use rate was 41%, with no sex difference but an age difference: infants were less terrestrial than juveniles and adults. DISCUSSION: Compared to a population with a more limited tool use repertoire (Fazenda Boa Vista), SCNP adult capuchins are more terrestrial (43% v. 27%). Stone tool use diversity and terrestriality in capuchins appear to be positively correlated. Our results support this hypothesis and provide terrestriality measurements of the wild capuchin population with the most complex stone tool kit.
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Cebus , Comportamento de Utilização de Ferramentas , Animais , Humanos , Brasil , ÁrvoresRESUMO
The environments in which neotropical primates live have been undergoing an intense fragmentation process, constituting a major threat to the species' survival and causing resource scarcity, social isolation, and difficulty in dispersal, leaving populations increasingly vulnerable. Moreover, the proximity of wild environments to anthropized landscapes can change the dynamics of pathogens and the parasite-host-environment relationship, creating conditions that favor exposure to different pathogens. To investigate the previous exposure of free-living primates in Rio Grande do Sul State (RS), southern Brazil, to the bacterial agents Leptospira spp. and Brucella abortus, we investigated agglutinating antibodies against 23 serovars of Leptospira spp. using the microscopic agglutination test and B. abortus acidified antigen test in primate serum samples; 101 samples from primates captured between 2002 and 2016 in different forest fragments were used: 63 Alouatta caraya, 36 Alouatta guariba clamitans, and 02 Sapajus nigritus cucullatus. In addition, the forest remnants where the primates were sampled were characterized in a multiscale approach in radii ranging from 200 to 1400 m to investigate the potential relationship of previous exposure to the agent with the elements that make up the landscape structure. The serological investigation indicated the presence of antibodies for at least one of the 23 serovars of Leptospira spp. in 36.6% (37/101) of the samples analyzed, with titers ranging from 100 to 1600. The most observed serovars were Panama (17.8%), Ballum (5.9%), Butembo (5.9%), Canicola (5.9%), Hardjo (4.9%), and Tarassovi (3.9%); no samples were seropositive for Brucella abortus. Decreased forest cover and edge density were the landscape factors that had a significant relationship with Leptospira spp. exposure, indicating that habitat fragmentation may influence contact with the pathogen. The data generated in this study demonstrate the importance of understanding how changes in landscape structure affect exposure to pathogenic microorganisms of zoonotic relevance. Hence, improving epidemiological research and understanding primates' ecological role in these settings can help improve environmental surveillance and conservation strategies for primate populations in different landscapes.
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Alouatta caraya , Brucelose , Cebinae , Leptospira , Leptospirose , Animais , Brucella abortus , Leptospirose/epidemiologia , Leptospirose/veterinária , Brucelose/epidemiologia , Brucelose/veterinária , Brucelose/microbiologia , Brasil/epidemiologia , Anticorpos AntibacterianosRESUMO
OBJECTIVES: Morphological variation in cranial sutures is used to infer aspects of primate feeding behavior, including diet, but strain regimes across sutures are not well documented. Our aim is to test hypotheses about sagittal suture morphology, strain regime, feeding behavior, and muscle activity relationships in robust Sapajus and gracile Cebus capuchin primates. MATERIALS AND METHODS: Morphometrics of sinuosity in three regions of the sagittal suture were compared among museum specimens of Sapajus and Cebus, as well as in robust and gracile lab specimens. In vivo strains and bilateral electromyographic (EMG) activity were recorded from these regions in the temporalis muscles of capuchin primates while they fed on mechanically-varying foods. RESULTS: Sapajus and the anterior suture region exhibited greater sinuosity than Cebus and posterior regions. In vivo data reveal minor differences in strain regime between robust and gracile phenotypes but show higher strain magnitudes in the middle suture region and higher tensile strains anteriorly. After gage location, feeding behavior has the most consistent and strongest impact on strain regime in the sagittal suture. Strain in the anterior suture has a high tension to compression ratio compared to the posterior region, especially during forceful biting in the robust Sapajus-like individual. DISCUSSION: Sagittal suture complexity in robust capuchins likely reflects feeding behaviors associated with mechanically challenging foods. Sutural strain regimes in other anthropoid primates may also be affected by activity in feeding muscles.
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Suturas Cranianas , Mastigação , Cebus/fisiologia , Sapajus/fisiologia , Animais , Masculino , Feminino , Análise de Variância , Modelos Lineares , Teorema de Bayes , Músculo Esquelético/fisiologia , Análise de Regressão , Mastigação/fisiologia , Suturas Cranianas/fisiologiaRESUMO
Masturbation is part of the natural behavioral repertoire of primates, with visual sexual stimuli known to trigger this behavior. Here, we report masturbation events triggered by visual sexual stimulus (VSS) in the South American primate Sapajus libidinosus. We observed a multi-male multi-female captive colony of 17 bearded capuchins between January and October 2014. Over this period, we registered 11 copulation events, 68 attempt copulations, and five masturbation events. The same low-ranking male (named Fu) performed all masturbation events. Fu directly looked at other individuals engaged in sexual displays while he masturbated in three events. The masturbation events associated with VSS lasted up to 2 min and 40 s. Our observations show that VSS can trigger masturbation in capuchin monkeys. The low hierarchy rank of the male, and the consequent lack of mating opportunities in the multi-male multi-female recently formed group in captivity, may have prompted the masturbation events.
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Cebinae , Masturbação , Animais , Masculino , Feminino , Humanos , Cebus , Comportamento SexualRESUMO
There are strong physiological and behavioral differences that allow animals to live in forests versus savannas. For example, terrestrial forest-dwelling mammals tend to be small compared to species living in savannas. Robust capuchin monkeys (genus Sapajus) are widespread in tropical South America, occurring in both forest and savanna environments, with forest species considered basal in an evolutionary context. Whether or not skull shape and size variations are associated with variation in resource use remains unknown, particularly for the two species living in savanna (Sapajus libidinosus and S. cay). Here we show that savanna species present convergent size and skull characteristics that may facilitate living in this new environment. Geometric morphometric methods were used to assess skull size and shape variation for 184 Sapajus specimens distributed across South America. We used phylogenetic generalized least squares to test size against environmental variables and multivariate morphological trajectories/partial least square analyses on the skull shape to detect shape differences in specimens between forest and savanna biomes. Our findings reveal Sapajus size reduction in the evolutionary transition from forest to savanna, a process related to increasing seasonality. Moreover, we found morphological parallelism in the skull (e.g., muzzle shortening) and (large) molars in the two savanna species, features that may facilitate the processing of harder food such as fallback resources. We associate these phenotypic differences to the evolutionary process of colonizing the savannas by primates (including early hominins), leading to morphological adaptations to tolerate stressful, seasonal environments, such as body size reduction and ingestion and mastication of tough foods.
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Platirrinos , Sapajus , Animais , Pradaria , Filogenia , Haplorrinos , Florestas , Cebus , MamíferosRESUMO
This work focuses on the distribution of LINE-1 (a Long Interspersed Nuclear Element) in primates and its role during evolution and as a constituent of the architecture of primate genomes. To pinpoint the LINE-1 repeat distribution and its role among primates, LINE-1 probes were mapped onto chromosomes of Homo sapiens (Hominidae, Catarrhini), Sapajus apella, and Cebus capucinus (Cebidae, Platyrrhini) using fluorescence in situ hybridisation (FISH). The choice of platyrrhine species are due to the fact they are taxa characterised by a high level of rearrangements; for this reason, they could be a useful model for the study of LINE-1 and chromosome evolution. LINE-1 accumulation was found in the two Cebidae at the centromere of almost all acrocentric chromosomes 16-22 and on some bi-armed chromosomes. LINE-1 pattern was similar in the two species but only for chromosomes 6, 8, 10, and 18, due to intrachromosomal rearrangements in agreement with what was previously hypothesised as through g banding. LINE-1 interstitial accumulation was found in humans on the 1, 8, 9, 13-15, and X chromosomes; on chromosomes 8, 9, and 13-15, the signal was also at the centromeric position. This is in agreement with recent and complete molecular sequence analysis of human chromosomes 8 and some acrocentric ones. Thus, the hypothesis regarding a link between LINE-1 and centromeres as well as a link with rearrangements are discussed. Indeed, data analysis leads us to support a link between LINE-1 and inter- and intrachromosomal rearrangements, as well as a link between LINE-1 and structural functions at centromeres in primates.
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Cebidae , Animais , Humanos , Cebidae/genética , Retroelementos/genética , Cariotipagem , Cebus/genética , Cromossomo X , Elementos Nucleotídeos Longos e Dispersos/genéticaRESUMO
PURPOSE: Habitat fragmentation is the main threat to primate survival in the world. Additionally, changes in the environments in which they live can also contribute to exposure to pathogens. To investigate some pathogens that free-living primates may be exposed to in Rio Grande do Sul State (RS; southern Brazil) and characterize the forest remnants in which they live, we investigated anti-Neospora caninum, Toxoplasma gondii, and Sarcocystis spp. antibodies in the serum of the animals. METHODS: We analyzed 105 serum samples from 63 black howler monkeys (Alouatta caraya), 39 southern brown howler monkeys (Alouatta guariba clamitans), and 03 capuchin monkeys (Sapajus nigritus cucullatus), which were captured in forest fragments of RS. Indirect fluorescence antibody test (IFAT) and indirect hemagglutination assay (IHA) were used to detect antibodies to the agents. We then characterized the landscapes in a multiscale approach in radii from 200 to 1400 m to investigate the relationship of the presence of the agents with landscape elements. RESULTS: In the IFAT-IgG, 13.3% (14/105) of the samples were seropositive for N. caninum, 4.8% (5/105) for T. gondii, and 5.7% (6/105) for Sarcocystis spp. In the IHA-IgM/IgG, 24.8% (26/105) were seropositive for T. gondii. The metrics that best explained exposure to agents were edge and patch density, forest cover, urban cover, and average Euclidean distance to the nearest patch. CONCLUSIONS: This study indicated that the primates were exposed to the agents studied, demonstrating that some landscape features are associated with exposures to the investigated pathogens.
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Alouatta , Coccidiose , Neospora , Sarcocystis , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários , Brasil/epidemiologia , Imunoglobulina G , Estudos Soroepidemiológicos , Toxoplasmose Animal/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterináriaRESUMO
This study had the purpose of understanding the effects of visitation on behavioral patterns and on the well-being of primates in captivity. Five Amazonian primate species were observed using the focal animal method: Ateles chamek, Ateles belzebuth, Ateles paniscus, Lagothrix cana, and Sapajus apella. Two categories of visitor behavioral observations were adopted - active and passive. From the total number of records, the behavior of primates could be observed in 53.7% of the notes in the presence of visitors. The behavior of the visitors in front of the cages was considered passive in 91.2% of those records. The three species of Ateles reacted in different ways in the presence and absence of visitors. The type of visitor behavior had influence on the behavior of the primate (Chi-square=22.9, p<0.001). Stress indicating behaviors (CIE) represented 3.3% of the behavioral repertoire of the species (n=253 records). The primates presented a varied number of CIE, which included indexes of reduced well-being levels. A. belzebuth was ranked first as the species most affected by visitation. These results show the importance of understanding the stress effects on the behavioral pattern of captive primates in relation to visitation and other factors, leading to alternative actions for the zoo in order to improve the level of their welfare.(AU)
O entendimento dos efeitos da visitação nos padrões comportamentais e no bem-estar dos primatas em cativeiro foi o objetivo deste estudo. Por meio do método animal focal foram realizadas observações de cinco espécies de primatas amazônicos: Ateles chamek, Ateles belzebuth, Ateles paniscus, Lagothrix cana e Sapajus apella. Para observações comportamentais dos visitantes, foram adotadas duas categorias, ativo e passivo. Do total de registros, encontrou-se que os comportamentos dos primatas foram exibidos em 53,7% das anotações na presença de visitantes. O comportamento dos visitantes diante dos recintos foi em 91,2% considerado passivo. As três espécies de Ateles reagiram de formas diferentes na presença e ausência de visitantes. O tipo de comportamento dos visitantes teve influência no comportamento dos primatas (Chi-quadrado=22,9, p<0,001). Os comportamentos indicadores de estresse (CIE) representaram 3,3% do repertório comportamental das espécies (n=253 registros). Os primatas apresentaram um número variado de CIE, apresentando indicadores de reduzido grau de bem-estar. A. belzebuth esteve em primeiro lugar no ranking das espécies mais afetadas pela visitação. Estes resultados mostraram a importância de compreender os efeitos do estresse no padrão comportamental dos primatas cativos relacionados a visitação e outros fatores, levando ao zoológico alternativas que conduzam a ações para melhorar o grau de bem-estar.(AU)
Comprender los efectos de visitaciones en los estándares comportamentales y en el bienestar de los primates en cautiverio fue el objetivo de este estudio. Mediante el método de animales focales se realizaron observaciones en cinco especies de primates amazónicos: Ateles chamek, Ateles belzebuth, Ateles paniscus, Lagothrix cana y Sapajus apella. Para observaciones comportamentales de los visitantes, se adoptaron dos categorías, activa y pasiva. Del total de registros, se encontró que los comportamientos de los primates se mostraron en 53,7% de las notas en presencia de visitantes. El comportamiento de los visitantes frente a los recintos fue considerado pasivo en un 91,2%. Las tres especies de Ateles reaccionaron de manera diferente a la presencia y ausencia de visitantes. El tipo de comportamiento de los visitantes influyó en el comportamiento de los primates (Chi-cuadrado=22,9, p<0,001). Los comportamientos indicadores de estrés (CIE) representaron el 3,3% del repertorio conductual de la especie (n=253 registros). Los primates presentaron un número variado de CIE, mostrando indicadores de un reducido grado de bienestar. A. belzebuth ocupó el primer lugar en el ranking de las especies más afectadas por las visitas. Estos resultados mostraron la importancia de comprender los efectos del estrés en el estándar comportamental de los primates en cautivos relacionados con las visitas y otros factores, llevando al zoológico alternativas que conduzcan a acciones para mejorar el grado de bienestar.(AU)
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Animais , Comportamento Animal , Bem-Estar do Animal , Interação Humano-Animal , Animais de Zoológico , Brasil , Atelinae , Técnicas de Observação do Comportamento/estatística & dados numéricos , SapajusRESUMO
Gastric cancer (GC) is the fifth most common type of tumor and the third leading cause of cancer death worldwide. The evolution of gastric carcinogenesis is still poorly understood and, for this reason, preclinical research protocols were established that included the development of gastric cancer cell lines and the establishment of models of gastric carcinogenesis in non-human primates such as Sapajus apella. A comprehensive literature search was performed in relevant databases such as PubMed, ResearchGate, and Google Scholar to identify studies related to the topic. After an in-depth study of these reports, significant data were collected and compiled under appropriate headings. The main result of the studies carried out by the group on GC is the demonstration of the MYC gene overexpression as a common phenomenon in stomach carcinogenesis. Furthermore, we revealed that reducing the expression of the CDC25B gene, regulated by the MYC protein, is a therapeutic strategy against stomach tumors. This review article reveals preclinical evidence that treatment with menadione in experimental models of gastric tumorigenesis, in vivo and in vitro, inhibits the action of the phosphatase CDC25B and, consequently, prevents cell proliferation, invasion, and migration.
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Neoplasias Gástricas , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Genes myc , Neoplasias Gástricas/metabolismo , Vitamina K 3/farmacologia , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismoRESUMO
Capuchins are platyrrhines (monkeys found in the Americas) within the Cebidae family. For most of their taxonomic history, the two main morphological types of capuchins, gracile (untufted) and robust (tufted), were assigned to a single genus, Cebus. Further, all tufted capuchins were assigned to a single species, Cebus apella, despite broad geographic ranges spanning Central and northern South America. In 2012, tufted capuchins were assigned to their genus, Sapajus, with eight currently recognized species and five Cebus species, although these numbers are still under debate. Alu retrotransposons are a class of mobile element insertion (MEI) widely used to study primate phylogenetics. However, Alu elements have rarely been used to study capuchins. Recent genome-level assemblies for capuchins (Cebus imitator; [Cebus_imitator_1.0] and Sapajus apella [GSC_monkey_1.0]) facilitated large scale ascertainment of young lineage-specific Alu insertions. Reported here are 1607 capuchin specific and 678 Sapajus specific Alu insertions along with candidate oligonucleotides for locus-specific PCR assays for many elements. PCR analyses identified 104 genus level and 51 species level Alu insertion polymorphisms. The Alu datasets reported in this study provide a valuable resource that will assist in the classification of archival samples lacking phenotypic data and for the study of capuchin phylogenetic relationships.
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Cebus , Sapajus , Elementos Alu/genética , Animais , Cebus/anatomia & histologia , Cebus/genética , Genômica , FilogeniaRESUMO
BACKGROUND: The aim of this work was to identify gram-positive bacteria and their respective resistance profiles of free-living capuchin monkeys. METHODS: For this, 15 Sapajus nigritus were captured in a municipal urban park in the northern region of the state of Paraná, Brazil, and under pharmacological restraint, samples were collected with sterile swabs from the oral, rectal, ocular, nasal, and auricular regions. After isolation of the 22 gram-positive bacteria, each isolate was subjected to the catalase and coagulase tests for presumptive identification. Subsequently, phenotypic tests for bacterial resistance were performed using the agar diffusion disc method. The samples resistant to oxacillin were submitted to the PCR technique to search for the mecA gene. RESULTS: Of the 22 gram-positive cocci of these two (9.09%) are Streptococcus spp. and twenty (90.91%) Staphylococcus spp. Among Staphylococcus spp. three (13.64%) were coagulate-negative (CoNS) and seventeen (86.36%) coagulate-positive (CoPS). Of the antimicrobials tested, enrofloxacin had the best performance, with only one (04.54%) isolate resistant to it, on the other hand, the antimicrobials with the lowest performance were cefotaxime and penicillin with 19 (82.36%) and 18 (81.81%) resistant isolates, respectively. Only five isolates had MAR less than 0.2, being one ocular, one oral, and three nasal, they had multiple resistance index varied between 0.07 and 0.92, with an average of 0.45 and a mode of 0.3. Among the samples with the highest resistance index, a positive coagulase Staphylococcus stood out, being intermediate to gentamicin and resistant to other antibiotics and an intermediate streptococcus to gentamicin, enrofloxacin, and resistant to other antibiotics. No sample was positive to mecA gene. CONCLUSIONS: Future studies should be conducted to identify the Staphylococcus species, the high rate of antimicrobial resistance of the monkeys in this study suggests that Grooming's behavior may be contributing to the sharing of the resistant microorganism among the members of this group of primates.
Assuntos
Anti-Infecciosos , Microbiota , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Coagulase , Farmacorresistência Bacteriana , Enrofloxacina , Gentamicinas , Primatas , Staphylococcus , StreptococcusRESUMO
When primates groom each other, they tend to concentrate on those parts of the body they cannot efficiently self-groom (i.e., not visually accessible), and prefer to intensify grooming in areas with high hair density, thus suggesting a hygienic function. However, preferences for some body sites over others during social grooming may also result from different degrees of social bonding and relative dominance. To assess the relative importance of physical (hygienic) and social factors, we examined grooming interactions in two groups of wild black capuchin monkeys (Sapajus nigritus) during 15 nonconsecutive months. We evaluated the distribution of social grooming across body sites according to their accessibility by self-grooming and hair density. At the same time, we assessed whether the degree of dyadic social bonding affects the relative body orientation between groomer and groomee and the access to vulnerable body sites (e.g., face, throat, groin) during grooming. As expected, capuchins preferentially groomed inaccessible body sites (e.g., back and head), with a disproportionate effort directed to the tufts of their partners. We found that dyadic social bond strength, together with rank distance, significantly affected the proportion of grooming in ventro-ventral body relative orientation only in dominant-subordinate groomer-groomee dyads. This may indicate that, when two individuals differ in rank but are strongly bonded, the level of uncertainty related to the social context is already resolved and thus grooming per se is no longer perceived by the subordinate as an uncertain/risky situation. We found no effect of social bonding on grooming vulnerable body sites for any type of dyad. Our findings suggest that grooming site preferences in black capuchin monkeys simultaneously reflect hygienic and social functions.
Assuntos
Cebus , Comportamento Social , Animais , Asseio Animal , Haplorrinos , SapajusRESUMO
In studies of simple and conditional discrimination, procedures are needed to measure those aspects of stimuli that control behavior. The blank comparison procedure is one such procedure. It was designed explicitly for assessing S+ and S- functions when discriminative stimuli are presented simultaneously. In this procedure, a neutral stimulus serves sometimes as S+ and sometimes as S-. Its discriminative function is defined in relation to other stimuli in the display. The present study aimed to prepare 2 infant female capuchin monkeys for the effective use of the blank comparison procedure in a simple discrimination task. First, simple discrimination training was applied up to a stable accuracy criterion of ≥90%. This training was followed by the replacement of S+ and then of S- stimuli with new stimuli. Ultimately, trials with the blank comparison were introduced. Following this sequence, both monkeys immediately displayed highly accurate blank-comparison performances without the need for stimulus control shaping or other preparatory discrimination training. Thus, this procedure sequence may be an efficient, effective method for establishing blank-comparison baselines for experimental analyses of S+/S- discriminative functions and perhaps for other applications in teaching simple and conditional discrimination performances to this species and others.