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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Controle do comportamento por relações entre estímulos em Cebus apella. / Control of behavior by stimulus relations in Cebus apella.

Romariz da Silva Barros 09 December 1998 (has links)
Equivalência de estímulos, um fenômeno comportamental amplamente demonstrado em humanos, tem sido encontrada com dificuldades em não-humanos, provavelmente devido a dificuldades de procedimento. Controle não programado pela posição dos estímulos tem sido apontado como um fator que interfere no desempenho de "matching-to-sample" e que leva a resultados negativos em testes de propriedades definidoras de equivalência (reflexividade, simetria e transitividade). Duas linhas de pesquisa foram exploradas: 1) Posição como estímulo em discriminações condicionais e testes de propriedades emergentes e 2) Treino e testes de relações condicionais na ausência de correlação entre a posição e a função dos estímulos. Foram conduzidos quatro experimentos com três macacos Cebus apella, uma fêmea e dois machos. No Experimento I, os sujeitos foram submetidos a treino de discriminações condicionais e testes de propriedades emergentes com posições como estímulo. Resultados positivos nos testes foram encontrados quando as relações testadas eram topograficamente semelhantes às relações treinadas. No Experimento II, treinos de discriminações simples com três conjuntos de estímulos visuais (cores e formas arbitrárias) mostraram diferenças na "discriminabilidade" dos estímulos. No Experimento III os sujeitos foram submetidos a treino de pareamento por identidade e testes de reflexividade com dois dos três conjuntos de estímulos facilmente discriminados no Experimento II e mais três novos conjuntos de estímulos. Os resultados dos testes foram positivos quando os estímulos já tinham sido apresentados antes em treinos de discriminações simples simultâneas, que possivelmente funcionaram como um treino de "matching-to-sample" com atraso. No Experimento IV os sujeitos foram submetidos a treinos de relações condicionais arbitrárias e a testes de simetria, cujos resultados foram negativos. Escolhas corretas foram reforçadas em todas as tentativas, em todos os experimentos. Todas as tentativas de "matching-to-sample" eram com atraso zero. A interpretação dos dados baseia-se na suposição de que relações de equivalência são relações ambientais. O pré-requisito para a emergência das propriedades definidoras é a aquisição de controle por essas propriedades enquanto relações ambientais, o que demanda extenso treino. / Stimulus equivalence, a largely demonstrated behavioral phenomenon in humans has been hardly found in non-humans likely due to procedural difficulties. Unprogrammed control by stimulus position has been pointed as interfering with matching-to-sample performances, which leads to negative results in tests of equivalence defining properties (reflexivity, symmetry and transitivity). Two lines of research were pursued that investigate: 1) Location as stimulus in conditional discriminations and tests of emergent properties and 2) Training and tests of conditional relations with no relation between location and function of stimuli. Four experiments with 1 female and 2 male Cebus apella were conducted. In Experiment I subjects were submitted to training of conditional discriminations and tests of emergent properties with location as stimulus, with positive results when the tested relations were similar to those trained. In Experiment II, training of simultaneous simple discriminations with three sets of visual stimuli (colors and arbitrary forms) showed differences in discriminability of the stimuli. In Experiment III, with two of the easily discriminated stimulus sets and three new stimulus sets, subjects received training of identity matching-to-sample and reflexivity tests, with positive results when the stimuli had been presented before in simultaneous simple discriminations, that possibly functioned as delayed identity matching-to-sample. In Experiment IV, subjects were submitted to arbitrary matching-to-sample training, and to symmetry tests with negative results. Correct choices in all trials were reinforced. All matching-to-sample trials were zero-delay. Interpretation of data relay on the assumption that equivalence relations are environmental relations. The prerequisite for defining properties emergence may be the acquisition of control by these defining properties as environmental relations, which demand extended training.
162

Revisão taxonômica do grupo Moloch, gênero Callicebus Thomas, 1903 (Primates, Pitheciidae, Callicebinae) / Taxonomic review of Moloch group, genus Callicebus  Thomas, 1903 (Primates, Pitheciidae, Calicebinae)

Rafaela Lumi Vendramel 19 December 2016 (has links)
Callicebus Thomas, 1903 são primatas neotropicais que ocorrem nas bacias Amazônica e do Orinoco, na Mata Atlântica e em parte da Caatinga, do Chaco e do Pantanal. São reconhecidas 33 espécies para o gênero, divididas em cinco grupos: Moloch, Cupreus, Torquatus, Donacophilus e Personatus. O grupo Moloch inclui espécies amazônicas, distribuídas entre a margem esquerda do Rio Madeira e a margem direita dos rios Tocantins-Araguaia. A história taxonômica dos sauás do grupo Moloch revelou uma considerável confusão, taxonômica e nomenclatural, de forma que sua composição e o reconhecimento das categorias específica e subespecífica variaram frequentemente. Sendo assim, o objetivo do presente trabalho foi revisar taxonomicamente os Callicebus do grupo Moloch, reconhecendo, descrevendo ou redescrevendo os táxons do grupo, a fim de elucidar o número de táxons nominais que o compõe. Foram realizadas análises qualitativas e quantitativas a partir de espécimes depositados em coleções científicas. Os caracteres qualitativos referentes ao padrão de coloração da pelagem foram confrontados diretamente em mapas, visando constatar descontinuidades geográficas ou possíveis clinas. Os caracteres quantitativos referentes às medidas cranianas e dentárias foram submetidos a testes estatísticos de dimorfismo sexual, variação ontogenética e variação geográfica. A partir dos resultados, foi constatado que para as espécies do grupo Moloch, o padrão de coloração é a principal característica diagnóstica, não havendo diferenças significativas quanto à morfologia e morfometria craniana e dentária. Sendo assim, foram consideradas válidas sete espécies para o grupo Moloch, gênero Callicebus: C. moloch, C. cinerascens, C. hoffmannsi, C. baptista, C. brunneus, C. vieirai, C. miltoni, havendo ainda a sinonimização de C. bernhardi com C. moloch. / The titi monkeys, genus Callicebus Thomas, 1903 are primates that occur throughout the Amazon and Orinoco basins, in the Atlantic forest region and in parts of Caatinga, Chaco and Pantanal. There are 33 species of this genus divided into five groups: Moloch, Cupreus, Torquatus, Donacophilus, and Personatus. The Moloch group is composed of Amazon species, distributed between the left bank of Rio Madeira and right bank of the Tocantins-Araguaia rivers. The taxonomic history of the titi monkeys from the Moloch group revealed some nomenclatural problems, so that the species and subspecies category varied frequently. Therefore, the aim of the present study was to present a taxonomic revision of the Callicebus species from the Moloch group, describing and/or redescribing its taxa, and to clarify the number of nominal taxa within it. I perform qualitative and quantitative analysis using specimens deposited in zoological collections. The qualitative characters related to the color pattern were mapped, aiming to find geographical gaps or clines. The quantitative characters consisted of cranial and dental morphometry that were submitted to statistical tests of sexual dimorphism, ontogenetic and geographical variation. For these, I performed univariate and multivariate analysis. The results showed that, for the Moloch group species, the color pattern is the main diagnostic characteristic, not showing significant differences in the cranial and dental morphology and morphometry. Therefore, seven species of the genus Callicebus, Moloch group, are here considered taxonomically valid: C. moloch, C. cinerascens, C. hoffmannsi, C. baptista, C. brunneus, C. vieirai, C. miltoni, and the new synonymy of C. bernhardi with C. moloch.
163

A vigilância de primatas não humanos e a febre amarela silvestre no Brasil / The surveillance of non-humam primates and the sylvatic yellow fever in Brazil

Romano, Alessandro Pecego Martins 19 September 2012 (has links)
Submitted by Luanna Matias (lua_matias@yahoo.com.br) on 2015-03-17T11:06:01Z No. of bitstreams: 2 Tese - Alessandro Pecego Martins Romano - 2012.pdf: 2327686 bytes, checksum: 033dd453809133aad159a6730bbcab88 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luanna Matias (lua_matias@yahoo.com.br) on 2015-03-17T11:10:04Z (GMT) No. of bitstreams: 2 Tese - Alessandro Pecego Martins Romano - 2012.pdf: 2327686 bytes, checksum: 033dd453809133aad159a6730bbcab88 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-03-17T11:10:04Z (GMT). No. of bitstreams: 2 Tese - Alessandro Pecego Martins Romano - 2012.pdf: 2327686 bytes, checksum: 033dd453809133aad159a6730bbcab88 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-09-19 / This study sought to describe the use of surveillance of non-human primates in surveillance of Sylvatic Yellow Fever and evaluate the usefulness in the prevention of human cases in Brazil. The epizootic surveillance began its records in 1999 and expanded the activity and the number of notifications after 2006, when the deaths or illnesses of nonhuman primates came to be considered an event of epidemiological relevance and therefore compulsory notification, as currently defines the ordinance 104/GM/MS/2011. 2748 epidemics were recorded in non-human primates in Brazil. The confirmation of yellow fever occurred in 8.8% of notifications. It was characteristic of yellow fever during the study period, two epizootic epidemic periods, with dispersal occurring from areas of Northern and central west with subsequent spread to the South and Southeast regions. During the study period yellow fever hit areas unvaccinated populations where the activity of epizootic surveillance helped to identify affected areas preventing human cases were recorded. The surveillance of NHP revealed the involvement of other infectious agents possibly involved in epizootics reported and highlights the potential contribution of this surveillance strategy for other infectious causes of public health importance and has been identified as seropositive for other arboviruses in primate populations in free life, demonstrating that this surveillance strategy animal may be useful to other map areas of occurrence of other arboviruses. The surveillance strategy allowed animals to detect areas of circulation of YF virus and direct vaccination campaigns, especially in outbreak situations, preventing human cases of the disease and demonstrating its utility and contribution to the monitoring of YF. This monitoring strategy can be enhanced by broadening their purposes as may possibly contribute to the surveillance of other diseases as an important interface of human and animal health. / Este estudo buscou descrever o uso da vigilância de primatas não humanos na vigilância da Febre Amarela Silvestre e avaliar a utilidade na prevenção de casos humanos no Brasil. A vigilância de epizootias iniciou seus registros em 1999 e ampliou a atividade assim como o número de notificações depois de 2006, quando a morte ou adoecimentos de primatas não humanos passou a ser considerado um evento de relevância epidemiológica e, portanto, de notificação compulsória, conforme atualmente define a portaria 104/GM/MS/2011. Foram registradas 2.748 epizootias de primatas não humanos no Brasil. A confirmação para a febre amarela ocorreu em 8,8% das notificações. Foi característica da febre amarela no período do estudo, dois períodos epizoóticos epidêmicos, com dispersão das áreas de ocorrência a partir do norte e centro oeste com disseminação posterior para as regiões sudeste e sul. No período do estudo a febre amarela atingiu áreas de populações não vacinadas, na qual a atividade de vigilância de epizootias contribuiu para identificar áreas afetadas evitando que casos humanos fossem registrados. A vigilância de primatas não humanos revelou a participação de outros agentes etiológicos possivelmente envolvidos nas epizootias notificadas e destaca o potencial de contribuição dessa ferramenta de vigilância para outras causas infecciosas de importância em saúde pública assim como quando foi identificada sorologia reagente para outros arbovírus em populações de primatas em vida livre, demonstrando que essa estratégia de vigilância animal pode ser útil para outras arboviroses com importância em saúde pública. A estratégia de vigilância animal permitiu detectar áreas de circulação do vírus da FA e orientar as campanhas de vacinação, principalmente, em situações de surto, prevenindo casos humanos da doença e demonstrando sua utilidade e contribuição para a vigilância da FA. Essa estratégia de vigilância pode ser aprimorada ampliando as suas finalidades já que possivelmente pode contribuir para a vigilância de outras doenças como importante interface da saúde humana e animal.
164

Tuberculose em primatas não humanos mantidos em cativeiro: uma revisão / Tuberculosis in nonhuman primates in captivity: a review

Tatiana Almeida Valvassoura 06 February 2012 (has links)
A Tuberculose vem acometendo animais selvagens desde o surgimento das primeiras coleções organizadas. Particularmente, macacos são altamente suscetíveis as micobactérias, gerando grandes perdas econômicas para as instituições, além do risco de transmissão para o homem e animais. As principais micobatérias, que causam a doença em primatas em cativeiro, são o Mycobacterium tuberculosis e Mycobacterium bovis. Acredita-se que primatas do "novo mundo" são menos suscetíveis do que os do "velho mundo", entretanto observa-se que tuberculose tem sido documentada em várias espécies. A principal forma de transmissão é através de aerossóis contendo os bacilos. A doença pode evoluir para a forma ativa ou latente, dependendo do estado imunológico do animal. Os sinais clínicos podem ser insidiosos, com somente uma alteração comportamental, seguido por anorexia e letargia, alterações respiratórias ou simplesmente o animal pode aparecer morto no recinto. O diagnóstico clínico é difícil e problemático, sendo que muitas vezes as lesões consistentes com a doença só são observadas na necropsia. Por isso o uso de outras ferramentas de diagnóstico é importante, como o teste de tuberculinização, cultivo e isolamento bacteriano, que são os mais usados na rotina das instituições, e os exames radiográficos do tórax e abdômen, testes moleculares e sorológicos. Toda instituição que mantém primatas em cativeiro deveriam possuir programas de prevenção para evitar a entrada da micobactéria dentro da coleção, principalmente ao se adquirir novos animais. Por isso, o emprego de medidas de biossegurança é essencial para diminuir o risco de doenças para o homem e para os animais dentro das instituições. Essas medidas consistem na implantação de uma série de procedimentos e normas operacionais rígidas, como programas de quarentena, programas de saúde para os funcionários e formação de equipe capacitada e treinada. / Tuberculosis has been affecting wild animals since the arising of the first organized collections. Specially, monkeys are highly susceptible to mycobacteria, which cause great economic losses in the institutions, beyond the risk of transmission to man and animals. The main species of mycobacteria, that cause disease in nonhuman primates in captivity, are Mycobacerium tuberculosis and Mycobacterium bovis. It is believed that nonhuman primates from the "new world" are less susceptible than the "old world" ones, however it is noted that tuberculosis has been continually documented in several species. Aerosols that contain infectious bacilli are the main transmission mode. The disease can progress to active or latent form, which depends on the animal's immune status. The clinical signs can be insidious, with only a behavior change, followed by anorexia and lethargy, respiratory alteration or the animal can appear dead in the room. The clinical diagnostic is difficult and problematic, and often lesions are only observed at necropsy. Therefore, the use of other diagnostic tools is important, as the tuberculin skin test, bacterial culture and isolation, that are most used during the routine of institutions, and radiography of the chest and abdomen, molecular and serological tests. Every institution that maintains nonhuman primates in captivity should have prevention programs to avoid the entry of mycobacteria inside of collection, mainly when new animals are acquired. Thus, the use of biosecurity measures is essential to reduce the risk of disease in humans and animals within institutions. These measures consist in implanting series of rigid procedures and operational standards, like quarantine programs, health programs for employees and formation of the qualified team.
165

Detecção dos agentes etiológicos da malária em símios resgatados em regiões de Mata Atlântica de São Paulo / Detection of etiological agents of malaria in monkeys rescued in Atlantic Forest regions of São Paulo

Tasciane Yamasaki 28 April 2011 (has links)
Foram analisadas, para a detecção de plasmódios, 50 amostras de sangue de bugios (Alouatta guariba clamitans) resgatados de várias áreas circundadas pela Mata Atlântica, pertencentes à região metropolitana da cidade de São Paulo. Para tanto, 20 e 30 amostras das regiões de resgate norte e sul respectivamente, foram analisadas pelas técnicas de microscopia, análise molecular e sorologia. Apenas uma lâmina de animal proveniente da região sul foi positiva para Plasmodium sp. A fim de encontrar um consenso molecular (dois ou mais resultados idênticos em PCR), utilizamos três protocolos de PCR. A porcentagem de infecções por plasmódios, detectada por PCR foi de 13,3% (04/30) e 6.6% (02/30) para Plasmodium vivax e P. malariae respectivamente nos animais resgatados na região sul, enquanto que na região norte 25% (05/20) das amostras foram positivas apenas para Plasmodium vivax. As médias geométricas em imunofluorescência indireta (IFI) foram maiores para Plasmodium vivax, seguidas das médias para P. malariae e P. falciparum nas duas regiões. As porcentagens de positividade para anticorpos contra a proteína circumsporozoíta (CSP) foram 30% (9/30), 13,6% (3/22), 3,84% (1/26), 23% (7/30), 27,6% para Plasmodium vivax VK210, P. vivax VK247, P. vivax like, P. malariae/P. brasilianum e P. falciparum respectivamente em regiões ao sul e 10% (2/20), 30,8% (4/13), 11,1% (2/18), 15% (3/20), 33,3% (6/18) para P. vivax VK210, P. vivax VK247, P. vivax like, P. malariae/P. brasilianum e P. falciparum respectivamente em regiões ao norte. Com relação a positividade de anticorpos contra a proteína MSP-119, estas foram de 30% (9/30) para o sul e 10% (2/20) para o norte. Nenhuma amostra foi positiva para Pf- MSP119 / In order to detect Plasmodium, fifty blood samples of holler monkeys (Alouatta guariba clamitans), collected in areas surrounded by the Atlantic Forest and located in the metropolitan region of São Paulo city, were analysed. Thus, 20 and 30 samples from the northern and southern areas, respectivelly, were examined by microscopy techniques, molecular analysis and sorology. Only one animal slide from the Southern area was positive for Plasmodium sp. In order to achieve a molecular agreement (two or more identic results on PCR), three PCR protocols were applied. The percentage of Plasmodium infections detected by PCR was 13.3% (04/30) and 6.6% (02/30) for Plasmodium vivax and P. malariae, respectivelly, in animals collected in the Southern area. Meanwhile, in the Northern area, 25% (05/20) of the samples were exclusively positive for Plasmodium vivax. The geometric means titles in indirect immunofluorescence were higher for Plasmodium vivax followed by P. malariae and P. falciparum in both areas. Percentages of positive results for antibodies against circumsporozoite protein (CSP) were of 30% (9/30); 13.6% (3/22); 3.84% (1/26); 23% (7/30); 27.6% for Plasmodium vivax VK210, P.vivax VK247, P. vivax like, P.malariae/P.brasilianum and P. falciparum, respectively in Southern areas and 10% (2/20), 30.8% (4/13), 11.1% (2/18), 15% (3/20), 33.3% (6/18) for P. vivax VK210, P.vivax VK247, P. vivax like, P. malariae/P.brasilianum and P. falciparum, respectivelly, in Northern areas. Antibodies with positive results against MSP-119 protein were 30% (9/30) in the South and 10% (2/20) in the North. None of the samples were positive for Pf-MSP119
166

Estudo da freqüência de micoplasma no trato urogenital, conjuntiva e orofaringe de macacos silvestres (Cebus). / Study of mycoplasma frequency in the urogenital tract, ororpharynx, and conjunctiva of wild monkeys.

Renata Lopes Neto 03 September 2007 (has links)
Pesquisou-se a freqüência de Mollicutes na orofaringe, conjuntiva e trato urogenital de 58 macacos. Na orofaringe detectou-se Mollicutes em 55,17 % e Ureaplasma spp em 43,10%. As espécies identificadas nesta região foram: M. arginini (43,10%), M salivarium (41,37%), e M. pneumoniae (18,96%). No trato genital detectou-se Mollicutes em 27,58% sendo identificado M. arginini em 8,62%, A. laidlawii em 1,72 % e Ureaplasma spp em 32,75%. Na conjuntiva detectou-se Mollicutes em 29,31 % e A. laidlawii em 1,72 %. Os cultivos apresentaram limitações pelo alto índice de contaminação e obtiveram-se apenas dois isolamentos da conjuntiva. As espécies detectadas constituem-se o achado inicial destas bactérias em macacos no Brasil. / The frequency of Mollicutes in oropharynx, conjunctiva, and urogenital tract were accessed in 58 monkeys. In oropharynx, Mollicutes and Ureaplasma spp were detected in 55.17% and 43.01% of the samples, respectively. The identified species in this site included: M. arginini (43.10%), M. salivarium (41.37%), and M. pneumoniae (18.96%). In the urogenital tract, Mollicutes were detected in 27.58% of the samples; including M. arginini (8.62%), A. laidlawii (1.72%) and Ureaplasma spp (32.75%). In the conjunctiva, Mollicutes were detected in 29.31% and A. laidlawii in 1.72% of the animals. Mollicutes culture showed technical limitations because of the high level of contamination and only two isolates were obtained; both from conjunctival sites. The Mollicute specie surveillance of this study provided initial and new insights about these bacteria in Brazilian monkeys.
167

Estudo genético dos pigmentos visuais em primatas do Novo Mundo / Genetic study of visual pigments in the New World monkeys

Viviani Mantovani Amador 22 February 2016 (has links)
A visão de cores em vertebrados necessita de pelo menos duas classes de cones, (fotorreceptores presentes na retina) e a existência de um substrato neural para que os fótons de luz sejam comparados, processados e posteriormente resultar na sensação da cor. Primatas do Velho Mundo, incluindo humanos, apresentam visão de cor tricromata, enquanto que primatas do Novo Mundo apresentam um polimorfismo nos genes dos pigmentos visuais e, entre os primatas, são os únicos que podem apresentar indivíduos com visão dicromata ou tricromata. O polimorfismo encontrado em primatas do Novo Mundo ocorre devido à variabilidade dos genes que expressam as opsinas responsáveis por absorver comprimentos de onda médios ou longos. Os estudos genéticos das opsinas são essenciais para compreensão do processamento e da sensação de cores nesses animais, e podem ajudar a entender a evolução da visão de cores nos Primatas. O objetivo deste trabalho é caracterizar a diversidade dos pigmentos visuais (LWS/MWS e SWS1) das espécies de primatas do Novo Mundo através de análises genéticas e descrever a sequência de aminoácidos observados para estimar o pico de sensibilidade espectral das opsinas. Foram coletadas amostras de sangue, fezes e/ou pelo de seis gêneros de primatas provenientes de diferentes regiões do Brasil (Pará, Rio de Janeiro, Rio Grande do Norte e São Paulo) e pertencentes às espécies Cebus apella, Callithrix jacchus, Alouatta clamitans, Alouatta caraya, Lagothrix lagothricha, Ateles belzebuth e Brachyteles arachnoides e posteriormente foram analisados os genes que expressam as opsinas nesses indivíduos. As sequências de aminoácidos encontradas nas posições importantes do gene SWS1 (52, 86, 93, 114 e 118) foram diferentes para algumas espécies. No gene SWS1 as espécies C. apella, L. lagotricha, A. belzebuth e B. arachnoides apresentam a sequência de aminoácidos LLPAT e as espécies C. jacchus, A. caraya e A. clamitans apresentaram a sequência de aminoácidos LLPGT. Foi descoberto que variações de aminoácidos na posição 50 do gene SWS1 em primatas do Novo Mundo podem ser importantes na determinação do pico de absorção espectral dos pigmentos expressos por este gene. Os genes LWS e MWS de indivíduos da espécie C. jacchus foram estudados e os aminoácidos localizados nas posições 180, 277 e 285 das opsinas foram identificados. Os resultados dos alelos encontrados nesses grupos tiveram cinco combinações diferentes (SFT, SYA, SYT, AYA e AYT), os alelos AYA e SYA foram descritos pela primeira vez neste grupo e a partir do resultado genético foi inferido o pico de absorção espectral da opsina. Este trabalho preencheu algumas lacunas da bibliografia e trouxe novas informações a respeito da diversidade genética dos pigmentos visuais em primatas do Novo Mundo / Color vision in vertebrates requires the presence of at least two different classes of cones in the retina, and a neural substrate capable to compare the activation of the different photoreceptors, which ultimately leads to color perception. Old World Monkeys (OWM), including humans, have trichromatic color vision, whereas New World Monkeys (NWM) have visual pigment genes polymorphism and among primates, are the only group with dichromatic or trichromatic individuals in the same species. This polymorphism in NWM occurs due to the variability of genes that express the opsins responsible for absorbing medium or long wavelengths. The genetic studies of color vision are fundamental for the comprehension of color perception in these animals and it could help to understand the color vision evolution in Primates. The aim of this work is to characterize the visual pigment diversity (LWS/MWS and SWS1) in NWM species by genetic analysis and estimate the opsin spectral absorption peak, based on the amino acid sequence. Blood, feces and hair were collected from six primate genres from different regions of Brazil (Pará, Rio de Janeiro, Rio Grande do Norte and São Paulo): Cebus apella, Callithrix jacchus, Alouatta clamitans, Alouatta caraya, Lagothrix lagothricha, Ateles belzebuth and Brachyteles arachnoides. The amino acid sequences found in important positions of the SWS1 gene (52, 86, 93, 114 and 118) were different among some species. In C. apella, L. lagotricha, A. belzebuth and B. arachnoides was found the amino acid sequence LLPAT. In C. jacchus, A. caraya and A. clamitans the amino acid sequence was LLPGT. It was observed in previous studies that residue 50 of the SWS1 gene in the New World primates is important to determining the spectral absorption peak of the visual pigments expressed by this gene. The LWS and MWS genes of C. jacchus have been studied and the amino acids located at positions 180, 277 and 285 have been identified. Five different combinations were found among the individuals analyzed: SFT, SYA, SYT, AYA and AYT. Two alleles, AYA and SYA, were described for the first time in this species. The present study filled some gaps in the literature and brought new information on the genetic diversity of visual pigments in New World primates
168

Assessment of lateralized behaviour in free-ranging Mexican mantled howler monkeys (Alouatta palliata mexicana)

Crespo Mingueza, Laia January 2015 (has links)
The evolutionary origins of human handedness are still unknown. The study of lateralized behaviour in our closest relatives, the nonhuman primates, is useful to clarify how this trait appeared and evolved in our species. In the present study, lateralized behaviour was assessed in a population of 32 free-ranging Mexican mantled howler monkeys (Alouatta palliata mexicana) for thirteen spontaneous motor patterns, at individual and group levels, as well as the effect that age, sex and posture have on its strength and direction. The studied population of howler monkeys displayed only few significant lateral biases at the individual level with single motor patterns (Binomial tests, p≤0.05). No biases towards the use of a particular limb or side of the body were found at a population level. Therefore, even though some individuals showed significant limb/side preference with single motor patterns, no signs of task specialization, side specialization, or true handedness were found. Similarly, no effects of sex, age or posture were found on the direction or strength of lateralized behaviour. The general absence of limb/side preferences found in this population may be due to the constraints imposed by the arboreal life and/or the type of diet. Possible causal agents of the few significant individual biases found here may be the presence of handicaps and/or experience. Further research is needed in order to assess whether the lack of human-like handedness reported in this study is only specific to the studied population, a general phenomenon of the genus Alouatta or perhaps of all the Platyrrhini.
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Taste responsiveness of black-handed Spider Monkeys (Ateles geoffroyi) to ten substances tasting sweet to humans

Pereira, Sofia January 2020 (has links)
Studies on taste perception in nonhuman primates contribute to the understanding of the evolution of the sense of taste. To assess the responsiveness of four adult spider monkeys (Ateles geoffroyi) to a set of substances perceived as sweet by humans, two-bottle preference tests were performed to determine taste preference thresholds, and taste-induced facial responses were analyzed. The spider monkeys displayed a significant preference for concentrations as low as 0.2-1 mM acesulfame K, 0.002-0.5 mM alitame, 10-20 mM isomalt, 0.002-0.5 mM sodium saccharin, 2-20 mM galactose and 20-50 mM sorbitol over water. The spider monkeys were generally unable to perceive aspartame and, based on their facial responses, probably do not perceive it as sweet. Thaumatin and monellin were not detected, and most likely neither was the sweetness of sodium cyclamate. Sodium saccharine and sodium cyclamate were rejected at high concentrations by at least one monkey, which is congruent with the perception of a bitter side taste as reported in humans. A significant correlation was found between the ranking order of sweetening potency for the different substances of spider monkeys and humans, but not between spider monkeys and chimpanzees. The results suggest that spider monkeys may be generally more sensitive than chimpanzees and at least as sensitive as humans to the tested substances, supporting the notion that high sensitivity to sweet taste may be associated with a frugivorous dietary specialization. The lack of responsiveness to some of the substances supports the notion of a dichotomy in sweet-taste perception between platyrrhine and catarrhine primates.
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Relationships Between Personality Type and Cognitive Ability in Marmoset Monkeys (Callithrix jacchus)

Marciano, Zachary 29 October 2019 (has links)
Personality refers to multiple traits that are thought to be stable over time and across situations. It is recognized that personality has a neural basis and is associated with health outcomes. Whether personality is also associated with cognitive ability, however, is still a matter of intense debate. One way to examine these potential relationships is to use a nonhuman primate model for which complexities present in humans can be minimized. Recent research into the varying personality types of marmoset monkeys suggests that there are predominantly three to five core primary domains that most marmosets and other primates can be categorized into, such as dominance, sociability, and neuroticism. The aim of the proposed study was to categorize a small colony of marmosets into respective personality domains, and to examine correlations between the monkeys’ personalities and their cognitive ability. This study was be conducted on 27 marmoset monkeys (14 male, 13 female) housed in the Lacreuse lab at the University of Massachusetts Amherst. A personality survey based on Koski (2015) containing 55 personality traits was utilized by 8 human judges, all of whom have been working with these monkeys daily for at least one year. Each judge rated each individual monkey on each individual trait on a 1 to 7-point scale; 1 indicating total absence of a trait and 7 indicating extreme presence of a trait. Once the survey data was compiled, a principal component analysis (PCA) was conducted to condense the myriad of ratings into smaller distinguishable personality domains. Three personality types were identified in this population, consistent with other non-human primate species. An ICC(2) was performed to ensure the interrater reliabilities of the 8 judges were consistent enough to be considered. Lastly, a linear regression was conducted to reveal possible correlations between the observed personality domains and cognitive performance achieved in a reversal learning task. The results of this experiment showed no statistically significant relationships between any of the three personality domains: Assertiveness, Neuroticism, and Inquisitiveness with the reversal learning cognitive scores. Although these findings suggest that personality and cognitive flexibility are independent in marmosets, we cannot rule out that personality may influence other cognitive domains. Additional studies are needed to examine this possibility.

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