Navegando por Assunto "Cebus apella"

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Alterações hepáticas por exposição a baixas doses de metilmercúrio em macacos prego, Cebus apella (Linnaeus 1758)
(Universidade Federal do Pará, 2011-09-16) SILVA, Márcia Cristina Freitas da; SILVEIRA, Luiz Carlos de Lima; http://lattes.cnpq.br/9383834641490219
Cebus apella were exposed to 1,5 ppm methylmercury (methylHg) in the diet for 120 days. Hepatotoxicity was investigated, concentrations of mercury in total blood were monitored each 30 days using atomic absorption spectrometry with cold vapor Hg201, aspartate transaminase (AST), alanine transaminase (ALT) and total bilirubin (BT) were determined. Liver was fixed by formaldehyde 10% and prepared by histopathology protocols. Significant difference was observed in groups exposed and control about total mercury (Hgtotal) in the periods of 60, 90 (P < 0,05) and 120 days (P < 0,01). The histopathology revealed moderate steatosis and hydropic degeneration, common in methylHg exposed in other species. No Significant difference between the levels of AST (p= 0.38), ALT (p= 0.83) and BT (p= 0.07) in groups exposed and control. The Pearson correlation with Hgtotal was negative (AST r= -0,7; ALT r=0,07; BT r= -0,3 e p > 0,05), suggests another studies to clarify the alert levels of mercury concentrations and liver dosages.
Acesso aberto (Open Access)
Alterações histopatológicas dos rins de macacos prego, Cebusapella (Linnaeus 1758) após exposição crônica a baixas doses de metilmercúrio
(Universidade Federal do Pará, 2014-02-28) SOUSA, Andréa do Socorro Campos de Araújo; SILVEIRA, Luiz Carlos de Lima; http://lattes.cnpq.br/9383834641490219
Mercury has been a major environmental and occupational risk and it still remains a problem for human health in the Amazon region. Although studies have shown that mercury affects various tissues and organs, kidneys are the target organs to the metal toxicity. Thus, the aim of this study was to investigate the effects of chronic exposure to low doses of methylmercury on renal parenchyma of Cebusapella, adult males exposed during 120 consecutive days with daily oral doses of 1.5 μg in the diet. The concentrations of total mercury in the animals’ blood were monitored every 30 days using a cold vapor atomic spectrophotometer (201 Hg), compared to the control group. The method used for histopathological analysis was the immersion in paraffin for staining with hematoxylin and Eosin, Masson's CAB and PAS. The immunohistochemical investigations included reactions for detection of smooth muscle actin ( IA4 ), muscle actin ( HHF35 ) and cytokeratin (AE1 and AE2). The results showed that treatment with mercury caused significant differences (P < 0.001) between the exposed and control groups. As for total Hg levels, histopathologicalchanges just likehydrops in Proximal tubuleswere observed, a common finding in methylmercury exposure in other species, with no significant changes in creatinine and urea concentrations. The Person correlation test showed a strong negative relationship between mercury concentration and animal body weight loss (P < 0.0001). Another important finding was the decrease in mesangial cells number, which suggests that methylmercury executed its nephrotoxicity, affecting not only the renal tubular system, as well as the glomerular mesangium cells, making necessary a greater amount of experimental studies to clarify which mercury concentration alert level is capable of triggering aggression mechanisms and kidney injury in subjects exposed to methylmercury.
Acesso aberto (Open Access)
Aquisição de relações condicionais simétricas e não simétricas e formação de classes por Cebus apella
(Universidade Federal do Pará, 2010) SOARES FILHO, Paulo Sérgio Dillon; BARROS, Romariz da Silva; http://lattes.cnpq.br/7231331062174024
Difficulty in documenting class formation in non-human participants may be due to the use of standard training and testing procedures developed in the context of research with human participants. Differences among testing and training situation may produce a decrease in performance during test. Using capuchin monkeys (Cebus spp.) as subject, this study intended to compare acquisition curve of a symmetrical with non-symmetrical conditional relation tasks, with different baselines for each conditional relation trained. This comparative analysis may provide us with some evidence of class formation without the need of the stimulus equivalence standard test protocols. Two male capuchin monkeys (Cebus spp.) participated: a young-adult (M09) and an adult (M12), both with history of simple and conditional discrimination training. Six pairs of bi-dimensional stimuli were used (A1-B1, A2-B2, A3-B3, A4-B4, A5-B5, and A6-B6). The procedure comprised three phases. In Phase 1, a “preparatory” 0-delay arbitrary matching to sample training was carried out (A1-B1 and A2-B2). In Phase 2, a "consistent" or “symmetrical” arbitrary matching to sample training was carried out (A3-B3, A4-B4, B3-A3, and B4-A4). In Phase 3, a "inconsistent" or “non-symmetrical” arbitrary matching to sample training was carried out (A5-B5, A6-B6, B5-A6, and B6-A5). Subject M12 finished all phases of the experiment. The comparative analysis between symmetrical and non-symmetrical acquisition curves (subject M12) shows easier acquisition of symmetrical task than non-symmetrical relations, suggesting that the arbitrary related events are members of class. This data suggest that the comparison between acquisition curves, such as it is described here, is a promising way to evaluate class formation in non-human participants. Subject M09 was removed from experiment because his performance did not reach the criterion in phase 3.1. M09 results pointed the need of a refined control relations analysis during the MTS task, making possible to improve the training procedure.
Acesso aberto (Open Access)
Associação de emissões vocais de macacos-prego (Cebus apella, Primate, Cebidae) a contextos comportamentais em cativeiro
(Universidade Federal do Pará, 2008) MARQUES, Karoline Luiza Sarges; SILVA, Maria Luisa da; http://lattes.cnpq.br/2101884291102108; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
The vocalization is an important form of communication in primates, because the majority of the species lives in dense forests, what makes difficult visual communication at a distance. The Cebus apella species presents a rich vocal repertoire contextualized to diverse behaviors, as feeding, foraging, predators avoidance, contact, copulation, and others. Aiming to elaborate a vocalization data base of sixteen Cebus apella captive subjects, we collected, at the Experimental School for Primates biotery of Federal University of Pará, vocalizations emitted in natural occurrences (agonism, contact) and in designed experiments (individual meal and alarm). The vocalizations were recorded, edited, and the sonograms were made and analysed. At least ten distinct vocal emissions, grouped in different contexts (feeding, alarm, agonism and contact) and the behaviors without vocalizations were mapped. Our data confirmed that Cebus apella species, own an extensive vocal repertoire, with different calls associated to particular behaviors, exhibit sexual differences in calls and sound unity combinations, in agreement with indications of the cerebral plasticity and the social complexity of the species.
Acesso aberto (Open Access)
Avaliação da susceptibilidade do primata Cebus apella (Primates: Cebidae) à infecção experimental com diferentes inóculos de Leishmania (Leishmania) chagasi
(Universidade Federal do Pará, 2005) SANTOS, Dirceu Costa dos; SILVEIRA, Fernando Tobias; http://lattes.cnpq.br/8106158306299969
In Brazil, the monkey Cebus apella has been successfully used as a model for studying cutaneous leishmaniasis. Thus, we decided to investigate its usefulness as a model for visceral leishmaniasis. For this purpose, we used 10 specimens of C. apella: 7 males and 3 females, juveniles. All were born and raised in captivity. In the first experiment was realize with 6 monkeys divided in 2 groups, in the first group with 3 monkeys was inoculated with 30 x 106 promastigotes of L. (L.) chagasi (MCAO/BR/1998/M18011, Maranhão State) from stationary phase of cultures, while in the second group with 3 monkeys was inoculated 5 doses successive with 30 x 106 promastigotes (150 x 106) of L. (L.) chagasi (MCAO/BR/1998/M18011, Maranhão State) from stationary phase of cultures. In the second experiment were used 4 monkeys, divided in 2 groups was also inoculated with five pairs of salivary glands of Lutzomyia longipalps together with parasites. In the first group with 2 monkeys was inoculated with 30 x 106 promastigotes of L. (L.) chagasi, second group with 2 monkeys was inoculated 5 doses successive with 30 x 106 promastigotes (150 x 106). The inoculations were, intradermaly, into the base of the tail of the animals. The evaluation of infections was monthly and included clinical examination, IgG antibody response (IFAT). In monkeys inoculated with promastigotes only or in those inoculated with promastigotes plus the salivary glands of the flebotominae sand fly we have till now found no clinical manifestations of infection all the experiment, neither have demonstrated parasites in the bone-marrow or specific antibody response. These results suggest that C. apella monkey is able to resist against to infection by L. (L.) chagasi.
Acesso aberto (Open Access)
Avaliação do perfil da resposta celular observado em indivíduos da espécie Cebus apella expostos ao carcinógeno N-Metil-N-nitrosuréia (mnu) e tratados com o modificador da resposta imune canova®
(Universidade Federal do Pará, 2011-04-19) FEIO, Danielle Cristinne Azevedo; BRITO JÚNIOR, Lacy Cardoso de; http://lattes.cnpq.br/9705670940390281; LIMA, Patrícia Danielle Lima de; http://lattes.cnpq.br/3411620003450812
The Immune response modifier Canova® (CA) is a homeopathic drug indicated for patients with a depressed immune system, once this medicine appears to increase the innate immunity and induce an immune response against multiple and severe pathological conditions, including Neoplasms. This increase of innate immunity is due to its involvement in the proliferation and differentiation of hematopoietic cells and mononuclear differentiation induction in bone marrow cells. The chemical compound N-Methyl-N-Nitrosourea (MNU) is a alkylating agent powerful carcinogenic able to cause mutations, chromosomal aberrations and DNA methylation, that induce the imbalance in the defense system of the cell and thus stop mechanisms related to cellular metabolism. This compound has been widely used in the induction of experimental tumors. The goal of this work is to assess the pattern of hematopoietic cell response in Cebus apella primate species exposed to carcinogenic N-Methyl-N-Nitrosourea (MNU) and subjected to the treatment with the Immune response modifier Canova®, through the analysis of biochemical, haematological, immune and cell cycle. We had used 13 (thirteen) adult animals of the species Cebus apella divided into five main groups: the control (negative and positive) and experimental (composed of three subgroups). The first experimental group received the MNU during thirty-five days, the second received treatment with Canova during three days, and the third received the MNU during 35 days and the end of this period received treatment with Canova during three days. Evaluation of cellular immune response was through immunophenotyping (CD3, CD4, CD8, T, B, NK) and complete blood count, liver and kidney function through biochemical analysis (ALT, AST, GGT, urea and creatinine) and kinetic evaluation of cell cycle by flow cytometry. Analysis of haematological values of hemoglobin, hematocrit and red blood cells of positive control groups performed significantly lower when compared to the negative control groups, demonstrating an anemia, while the increased white lineage cells in these groups is probably due to the animal's inflammatory response to neoplastic process. The increase of leukocytes has also been observed in experimental groups treated with the CA, a fact explained by the action of this drug, which acts as a modifier of immune response. Although it has been reported that CA can act by increasing the number of neutrophils, in this study we did not observe this action of the medicinal product, probably by the short time of treatment. Monocytes were decreased in the group treated with MNU and risen in groups that received CA probably by drug act in the activation of macrophages via stimulation of monocytes. In biochemical analysis, urea and creatinine were changed in the groups that received the MNU acutely, these changes, as well as those found in the analysis of liver enzymes, can be associated with typical symptoms of poisoning by carcinogenic drugs. Analysis of cell cycle kinetics of animals treated with CA, there had been a significant increase in cell G0-G1 as well as the percentage of cells in cellular proliferation stage (stageG2-M). We found that CA had minimized the toxicity of the MNU in certain haematological and biochemical, we had observed their partially skill to modify immune response, as improve white blood cell count, but without changing the pattern of immunological markers. Then CA is able to restore some hematopoietic system components and can act as an adjuvant in chemotherapy treatments.
Acesso aberto (Open Access)
Avaliação do perfil de metilação e expressão do gene CDH1 em Cebus apella como modelo experimental para câncer gástrico
(Universidade Federal do Pará, 2012-07-09) ANTUNES, Symara Rodrigues; BORGES, Barbara do Nascimento; http://lattes.cnpq.br/0676220027193876; ANSELMO, Nilson Praia; http://lattes.cnpq.br/6518287721873199
The gastric cancer remains a major cause of death among cancers in the world. In Brazil, are expected around 500 000 new cases in 2012/2013. The origin of stomach cancer, as in others, arises from the accumulation of genetic alterations. Therefore, it is necessary to know which genetic changes are important in triggering the pathogenesis of gastric cancer. We know that the intestinal type develops through well defined stages. The MNU - a known carcinogen - when ingested in oral form at dosages determined triggers development of this histological type of gastric cancer. Based on this knowledge, we conducted an experiment with six specime of Cebus paella, induced to develop intestinal type gastric cancer. The animals consumed 16mg/kg of body weight daily drugs. All pre-neoplasic lesions developed. Due to drug toxicity, only one survived the entire treatment and developed a tumor. Periodic evaluations were made of animals in pre-determined days (the beginning, days 120, 150, 300, 940) during which samples were made of the gastric mucosa. We collected 20 samples of tissue, distributed among normal mucosa, gastritis, dysplasia, metaplasia, and tumor. DNA extracted from these samples for further analyzes of the CDH1 gene. There is no sequence of this gene in the literature for the species under study. So the first step was to get this sequence. Using the initiators constructed from sequences of CDH1 Callithrix jacchus (species phylogenetically closer to C. apella) we get a sequence of 342pb. There is a similarity of 98% with humans, the presence of binding sites for transcription factors like (sp1, Ap2, NF-x, AREB6, Puf and CTF) and the presence of CAAT Box. The sequence has 30 CpG sites could suffer epigenetic regulation. We also performed MSP analysis with specific primers and found that the region analyzed, there was predominance of the unmethylated CDH1 alleles for all samples pre-neoplastic and adenocarcinoma sample is methylated. When we compared these data with immunohistochemistry revealed that only tumor sample did not express the protein cadherin. Our analyzes suggest that methylation of the CDH1 gene plays an important role in gastric tumorigenesis in C. apella. And, from the similarity between sequences, we suggest that the same occurs in humans. This cadherin promoter methylation leads to inactivation of the gene and establishment of gastric adenocarcinomas. The cadherin promoter hypermethylation has been reported in several articles associated with the development of gastric cancer.
Acesso aberto (Open Access)
Avaliação do uso de nanopartículas lipídicas que se ligam a receptores celulares como instrumento para a terapêutica do câncer
(Universidade Federal do Pará, 2014-12-19) FEIO, Danielle Cristinne Azevedo; LIMA, Patrícia Danielle Lima de; http://lattes.cnpq.br/3411620003450812
Lipid-based nanoparticle systems have been used as vehicles for chemotherapeutic agents in experimental cancer treatments. More recently, those preparations have also been assayed in animal models of cardiovascular, rheumatic and other chronic inflammatory diseases. In general those systems reportedly attenuate the severe toxicities of chemotherapeutic agents. This study was aimed to investigate the effects of associating paclitaxel to a lipid-based nanoparticle system upon the organism of a non-human primate, Cebus apella, by extensively documenting the toxicity by serum biochemistry, hematological and detailed histopathological methods. The lipid nanoparticles (LDE) were constituted of cholesterol esters and esterified cholesterol, lecithin and triolin, with addition of paclitaxel. Eighteen Cebus apella were studied; three animals were treated with LDE only, without paclitaxel, as ministered intravenously every three weeks, during six treatment cycles; six animals were treated with paclitaxel associated to LDE at the same administration scheme, three with the lower (175mg/m2) and three with higher (250mg/m2) paclitaxel doses; six animals were treated with commercial paclitaxel, three with the lower and three with the higher doses levels. Three weeks after the treatment cycle the animals were euthanized by lethal anesthetic dose, and tissues fragments were collected for histopathological analysis. In three non-treated animals, the plasma kinetics of LDE’s labeled with radioactive cholesterol was determined after intravenous injection and blood sampling over 24 hours. The ethics committee in research with experimental animals UFPA (BIO008-11) approved the project. In the LDE-paclitaxel group, no clinical toxicity appeared, and the weight food consumption curve were similar to controls. Treatment was interrupted after the second cycle in four animals of commercial paclitaxel group for very high clinical toxicity but the remaining two complete the 6-cycle-treatment. Those two animals presented weight loss, nausea and vomiting, diarrhea, escame decamation, 70% fur loss and loss of physical activity. The 175mg/m2 paclitaxel dose is used in cancer chemoterapie with considerable toxicity, while the 250 mg/m2 dose shows intorable toxicity to the patients. The use of LDE as carrier in both those levels was almost complete neutralized the toxicity of the drug in this species more closed related to human subjects. This was observed not only by clinical, biochemical and hematological profiles but also by the histopathological analysis of stomach, small and large intestine, esophagus, pancreas, trachea and gallbladder. The current results support the assumption that lipid-based nanoparticles systems used was drug carriers can offer valuable tools decrease the toxicity and increase the safety of the chemotherapeutic agents, while extending the use to chronic diseases other than cancer.
Acesso aberto (Open Access)
Avaliação dos marcadores de injúria miocárdica induzida pela exposição ao metilmercúrio em modelos experimentais de primatas do novo mundo (Cebus Apella)
(Universidade Federal do Pará, 2009-07-10) MAGNO, Ismaelino Mauro Nunes; QUARESMA, Juarez Antônio Simões; http://lattes.cnpq.br/3350166863853054
This study aimed to examine effects of the mechanisms of injury producing cellular damage in the heart of the monkey Cebus apella exposed for 120 consecutive days, with daily dose of 1.5 methyl Hg, by changes detected in biochemical markers of myocardial injury CK - MB, the histopathological findings as well as the technique of immunolabeling of apoptotic cells. For that, we related to the serum profiles of CK-MB, total CK, AST, ALT, urea, creatinine and total bilirubin with the histopathological and immunohistochemical findings in the involvement of the heart muscle during exposure to methyl Hg, and compared with a control group. The method used for determination and analysis of the serum and the determination of mercury in blood was the kinetic ultraviolet; atomic absorption spectroscopy, respectively; for histopathological analysis used the technique of Hematoxylin and Eosin; and for detection of apoptotic profiles the method APOPTAG. Was obtained information that correlate the biochemical changes, histopathologic profiles and apoptotic mechanism of cardiac involvement in three animals exposed to methyl Hg, when compared with control group. Among all substances of biochemical analysis were found that there was only marked increase of serum CK-MB enzyme, whereas, the histopathologic analysis showed reversible cell damage by accumulation of water in the three organs examined (heart, liver and kidney). It is also the observation of a clear labeling of apoptotic cells in heart, liver and kidney tissues of exposed animals, showing a higher number of positive cells in cells of renal tubules. Emphasizing that there was no inflammatory infiltrate around these tissues described and analyzed, and was there absence of such lesions in tissues of three control animals. It was concluded that the enzyme CK-MB, the hydropic degeneration and the mechanism of apoptosis may be indicators of myocardial injury in acute exposure to methyl Hg whose pathogenesis could be related to mitochondrial decompensation because massive commitment of the Na + / K + and Ca + + pumps. Requiring a greater intake of experimental studies that can clarify the exact pathogenesis, the mechanism of cellular injury and aggression in individuals exposed to toxic doses of methyl Hg.
Acesso aberto (Open Access)
Bem estar em cativeiro: análise e planejamento da ocupação do tempo em macacos-prego (Cebus apella)
(Universidade Federal do Pará, 2009) LESSA, Miguel Angelo Monteiro; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
Foraging is one of the most important activities and consuming great part of the day time of neotropical primates in the natural environment. In the wild, Capuchins spend up to 80% of their time traveling and foraging in the search for food. On the other side, in captivity no effort is usually required to obtain food. Therefore the opportunity to express foraging activities becomes virtually excluded in captivity. The main objective of this work was to create and evaluate the effectiveness of an environmental enrichment tool called “bowlboard”, designed to difficult access, extending the time devoted to reach food. The observation was carried through in four different contexts, being one in the morning and three in the afternoon, using a focal animal sampling method. The relative duration of each behavioral event was compared in the absence and presence of the enrichment. It was found that the bowller extended foraging time, functioning as instrument of environmental enrichment. A considerable lowering in frequency of abnormal behaviors, while search and manipulation of food was more time consuming.
Acesso aberto (Open Access)
Cebus cf. apella exhibits rapid acquisition of complex stimulus relations and emergent performance by exclusion
(2010-12) BRINO, Ana Leda de Faria; ASSUMPÇÃO, Ana Paula Bemerguy; CAMPOS, Rodolfo da Silva; GALVÃO, Olavo de Faria; MCILVANE, William J.
A "second generation" matching-to-sample procedure that minimizes past sources of artifacts involves (1) successive discrimination between sample stimuli, (2) stimulus displays ranging from four to 16 comparisons, (3) variable stimulus locations to avoid unwanted stimulus-location control, and (4) high accuracy levels (e.g., 90% correct on a 16-choice task in which chance accuracy is 6%). Examples of behavioral engineering with experienced capuchin monkeys included four-choice matching problems with video images of monkeys with substantially above-chance matching in a single session and 90% matching within six sessions. Exclusion performance was demonstrated by interspersing non-identical sample-comparison pairs within a baseline of a nine-comparison identity-matching-to-sample procedure with pictures as stimuli. The test for exclusion presented the newly "mapped" stimulus in a situation in which exclusion was not possible. Degradation of matching between physically non-identical forms occurred while baseline identity accuracy was sustained at high levels, thus confirming that Cebus cf. apella is capable of exclusion. Additionally, exclusion performance when baseline matching relations involved non-identical stimuli was shown.
Acesso aberto (Open Access)
Cognição animal: identidade generalizada e simetria em macaco-prego (Cebus apella)
(Universidade Federal do Pará, 2003-02-14) SANTOS, José Ricardo dos; BARROS, Romariz da Silva; http://lattes.cnpq.br/7231331062174024
Complex behavioral repertories, such as generalized identity matching and equivalence classes, have been easily found in normal humans, children, and youngsters with learning deficits. However, it is not easy to find such a positive results with non-human subjects. Symmetry is one of the most difficultly found defining properties of equivalence in nonhumans. It might happen because symmetry involves sample-comparison function reversals as well as modification in the sequence and position of stimuli presentation. The negative results in obtaining generalized identity matching and equivalence class formation in non-humans subjects may be related to incoherence between the SCT (Stimulus Control Topography) planned by the experimenter and the SCT presented by the subjects. So it suggests the necessity of a more specific methodological development. The present study proposed to apply the training and testing experimental procedures to obtain generalized identity matching and to verify the possibility of emergence of symmetry after arbitrary matching to sample training, through sample stimulus control shaping procedure and in the absence of correlation between the function and the positions of the stimuli. One capuchin monkey (Cebus apella) served as subject. He was young-adult and naive. Two experiments were executed. In the Experiment I, we carried out simple discrimination reversals training, conditional discrimination training, with an identity matching to sample procedure, and generalized identity test in extinction. The results showed that the procedure used to train simple discrimination (and reversals) was efficient as well as the procedure to train identity matching. All generalized identity tests reached positive results. In the Experiment II, we carried out arbitrary matching to sample training, with a sample stimulus shaping procedure in 8 steps, and one BA symmetry test. This study aimed to verify if elements positively related in conditional discriminations (AB training, for example) might be recombined by the subject without additional training. The performance of the subject in the BA symmetry test reached 100% of correct choices, showing that it is possible to obtain the property of symmetry in arbitrary conditional discriminations with non-humans subjects. The data also suggest that additional research has to be carried out in order to contribute to specifying the necessary conditions to obtaining complex repertory such as equivalence class formation in non-human subjects.
Acesso aberto (Open Access)
Comparação de dois procedimentos computadorizados para avaliação de discriminação de cores em Cebus sp
(Universidade Federal do Pará, 2009-11) MAKIAMA, Sheila Tetsume; GOULART, Paulo Roney Kilpp; http://lattes.cnpq.br/7800966999068746; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
Color vision consists in discrimination of objects based on their spectral composition, assisting in the organism-environment interaction. Among primates, it is estimated that the majority of the platyrrhines monkeys has a polymorphic and sex-linked dichromacy. The objective of this study was to compare the results produced by different equipments and softwares for assessment of tri/dichromatic conditions of two males and two females of the genus Cebus sp. Two computerized programs were used: one involving an adapted version of the Cambridge Colour Test and another one developed for a standard computational system. In Experiment 1 and 2 were possible to verify the trichromatic condition of one female subject and the dichromatic condition of the rest of the participants. In Experiment 3, a female and a male subject presented a dichromatic performance compatible to that one registered in previous experiments. In this Experiment, a female participant presented a trichromatic performance compatible to that one registered in previous experiments. It was concluded that favorable conditions for assessment of color vision in platyrrhines species can be built involving equipment and software with low financial cost and easy to program. However, due the few number of sessions with the low financial cost equipment, it is suggested the replication of the Experiment 3 and more sessions should be made with more subjects and involving new stimuli arrangement. It is believed that, if new data confirm the data produced here, this equipment and procedure can be used for evaluation of others platyrrhines species where behavioral data are scarce.
Acesso aberto (Open Access)
Comparison of two computerized procedures for the assessment of color discrimination in Cebus apella
(2011-12) MAKIAMA, Sheila Tetsume; GOULART, Paulo Roney Kilpp; GALVÃO, Olavo de Faria
Color vision consists of the discrimination of objects based on their spectral composition. Among primates, the majority of Platyrrhini monkeys are estimated to have polymorphic and sex-linked dichromacy. The objective of this study was to compare the results produced by different equipment and software for the assessment of tri- and dichromatic conditions in one male and two female Cebus apella. Three experiments were programmed. In Experiment 1, verifying the trichromatic condition of one female subject and dichromatic condition of the remainder of the subjects was possible using an adapted version of the Cambridge Colour Test. Experiment 2 confirmed the results of Experiment 1 using a different array of stimuli of the same test. Experiment 3, which produced results similar to Experiment 2, consisted of a test developed for a standard computer system using stimuli with color properties similar to the ones used in the previous experiment. Favorable conditions for the assessment of color vision in Platyrrhini can be built with low-cost equipment and software. Once data have been gathered with additional subjects and new stimulus arrangements have been tested and confirmed, the procedure can be used for the evaluation of other Platyrrhini species for which behavioral color discrimination data are currently lacking.
Acesso aberto (Open Access)
Conservação do sêmen e liquefação do coágulo seminal de macaco-prego (Cebus apella) em água de coco em pó (ACP-118®), em diferentes temperaturas
(2010-03) OLIVEIRA, Karol Guimarães; CASTRO, Paulo Henrique Gomes de; MUNIZ, José Augusto Pereira Carneiro; DOMINGUES, Sheyla Farhayldes Souza
The aim of this study was to evaluate the powdered coconut water (PCW) in the semen conservation and seminal clot liquefaction. The semen of six adult male Cebus apella was collected by electroejaculation (EEJ), diluted in ACP-118® extender and stayed in water bath at 33, 35 and 37°C for 24 hours. The sperm integrity was evaluated by eosin-nigrosine staining every one hour during the six initial hours and after 24 hours of incubation. The average volumes and sperm concentrations of clotted and liquid fractions were 0.20±0.02 and 0.20±0.10mL, 1.1±0.3x108 and 1.3±0.9x107 sperm mL-1, respectively. Immediately after collection, only in a sample of liquid fraction was observed 20% motility and vigor 4, which stopped after 40 minutes. Most of the clot was liquefied in ACP-118® after 12 hours of incubation. The best observed treatment was 33°C, because it kept 47±12.8% of sperm integrity after 24 hours. It was concluded that the PCW extender is effective in the liquefaction of seminal clot and maintenance of sperm viability 24 hours after the EEJ at 33, 35 and 37°C.
Acesso aberto (Open Access)
Desenvolvimento comportamental manipulativo e ocorrência de olhar mútuo entre macacos-prego (Cebus cf. apella) em cativeiro
(Universidade Federal do Pará, 2011-11-07) JACOMETTO, Ingrid Schunlaus Nikolak; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
During the first two months of life the offspring of Cebus depend almost exclusively on their mother. Only after the third month the newborn starts to move around independently, and at that time major changes in their behaviors pattern occur, along with an increase in the manipulative repertoire. The objectives of this study are to monitor the development of manipulative behavior in three Cebus cf. apella newborns, and check the possible occurrence of mutual gaze between monkeys. In Experiment 1, using the focal animal sampling, it was observed the baseline frequency of the behavioral categories of manipulative behavior of three Cebus cf. apella newborns. Following, four types of objects were inserted in the cage, one every week. Experiment 2 was a simple discrimination test between pictures of faces with direct versus desviated gaze. Experiment 3 was a simple discrimination training, between two stimulus pairs: front faces with direct versus deviated gaze, and front face versus profile face. The results show that newborns of the same age group spent about the same time manipulating objects. It was not possible to observe a clear pattern of preference for direct or deviated gaze in Experiment 2. Subjects were able to discriminate gaze direction (Experiment 3).
Acesso aberto (Open Access)
Discrimination of complex visual stimuli in Cebus apella: identity matching with pictures
(2009-06) GALVÃO, Olavo de Faria; SOARES FILHO, Paulo Sérgio Dillon; NEVES FILHO, Hernando Borges; NAGAHAMA, Milena Monteiro
Do capuchin monkeys respond to photos as icons? Do they discriminate photos of capuchin monkeys' faces? Looking for answers to these questions we trained three capuchin monkeys in simple and conditional discrimination tasks and tested the discriminations when comparison stimuli were partially covered. Three capuchin monkeys experienced in simultaneous simple discrimination and IDMTS were trained with repeated shifts of simple discriminations (RSSD), with four simultaneous choices, and IDMTS (1 s delay, 4 choices) with pictures of known capuchins monkeys' faces. All monkeys did discriminate the pictures in both procedures. Performances in probes with partial masks with one fourth of the stimulus hidden were consistent with baseline level. Errors occurred when a picture similar to the correct one was available among the comparison stimuli, when the covered part was the most distinct, or when pictures displayed the same monkey. Capuchin monkeys do match pictures of capuchin monkeys' faces to the sample. The monkeys treated different pictures of the same monkey as equivalent, suggesting that they respond to the pictures as icons, although this was not true to pictures of other monkeys. Subsequent studies may bring more evidence that capuchin monkeys treat pictures as depictions of real scenes.
Acesso aberto (Open Access)
Efeito de diferentes histórias de treino sobre a ocorrência de "insight" em macacos-prego (Cebus spp.)
(Universidade Federal do Pará, 2010-03-17) NEVES FILHO, Hernando Borges; CARVALHO NETO, Marcus Bentes de; http://lattes.cnpq.br/7613198431695463
The origin of novel behavior is a multilayered phenomenon that comprehends several distinct processes. One of these processes is known as insightful problem solving. The "insight" could be explained as a result of a spontaneous interconnection of multiple previously learned behavioral repertoires. The objective of this study was to investigate if different performances of insightful problem solving could be produced by different training histories of behavioral prerequisites in Cebus spp. Six subjects were divided in two groups of three subjects each. The prerequisite repertoires taught were: 1) to join two different objects (joining), and; 2) to rake a box with food inside using a tool (raking). The subjects of the first group had an asymmetric training of the two prerequisite repertoires. In this group the joining ability had a short training with a low learning criterion, and an extensive training of the raking ability, with a high learning criterion. The subjects of this group had to obtain more than the double of the number of training sessions for raking, in comparison with the joining repertoire. The other group passed by a symmetric training of the two repertoires, with high learning criterions for both. The subjects of this group passed by the same number of training sessions of joining and raking. In the test situation, a two joinable pieces tool never before handled by the subjects were presented, with a box with food out of range that could only be reached with the joined tool. Most of the subjects successfully solved the final task, with consistent results depending on the type of training. Only one subject of the asymmetric group didn’t solve the task. The topographies of solving were highly dependable on the quantity of training of one repertoire in comparison to another.
Acesso aberto (Open Access)
Efeito do treino de discriminação simples sobre o repertório de pareamento ao modelo por identidade de um macaco-prego (Cebus apella)
(Universidade Federal do Pará, 2007-03-01) MAN, Tiago Sales Larroudé de; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
this paper reports an experiment training to verify the function of simple simultaneous discrimination training with pairs of stimuli on identity match-to-sample performance with the same stimuli. An infant capuchin monkey with experience with identity match-to-sample served as subject. It was investigated how much training with a Repeated Shift of Simple Discrimination (RSSD) procedure would facilitate performance in match-to-sample with the same stimuli. Response ratio to advance the procedure and duration of the intertrial interval (ITI) were manipulated, and discriminative training for all possible pairs of a four-stimulus set was undergone. Identity match-to-sample with set A was used as baseline. Set B was trained in simple discrimination and tested in identity matching-to-sample. Test trials were interspersed among baseline trials. Correct responses were followed by a grape-flavor sugar pellet of 45 mg, and started the ITI. Incorrect responses ended the trial and started the ITI. Results shows variable performances on identity tests and RSSD, indicating small contribution of RSSD to IDMTS when to choices are used in both. Discuss about wrong patterns on identity test yelded by contraditory Stimulus Topography Control selectioned by RSSD procedure.
Acesso aberto (Open Access)
Efeitos da manipulação do número de escolhas sobre o desempenho em tarefas de discriminação simples em macaco-prego (Cebus cf. apella)
(Universidade Federal do Pará, 2010-11) QUEIROZ, Lidianne Lins de; BRINO, Ana Leda de Faria; http://lattes.cnpq.br/9930065472602966; BARROS, Romariz da Silva; http://lattes.cnpq.br/7231331062174024
There are several variables that can affect the precision of repertoire acquisition in discrimination training. The number of choices presented in the discrete trials is still one variable little explored in the context of verifying in which situations the discriminative control is more easily established. The general objective of the present work is to describe the effects of the manipulation of the number of choices on performance in simple discrimination tasks in capuchin monkeys (Cebus cf. apella). In Experiment I, the subjects were given a discriminative training with three types of trials (2, 4, and 9 choices). A stimulus control test assessed if the acquired repertoire could be maintained when the stimuli used in the three types of trials were then presented in the two-choice fashion. Additionally, in Experiment II, we evaluated if the correct responses in previous discrimination training occurred due to selection of the S+, rejection of the S-, or mixed control (selection and rejection). This evaluation was carried out through a mask procedure. The results in Experiment I suggest that the exposure to a larger number of choices is an efficient strategy to establish the discriminated responses since the performance was accurate even when the number of choices was reduced to two. The results obtained in Experiment II show different data for the two subjects. M30 showed control by rejection and preference for mask and M31 showed mixed control. The present research shows a path to a more complete analysis of stimulus control in studies on the manipulation of the number of choices and indicates that this variable may be an efficient way to reduce the difficulty in acquisition of discriminations in applied context.