Navegando por Assunto "Macaco-prego"

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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)
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)
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)
Criopreservação do sêmen de macaco-prego (Sapajus apella Linnaeus, 1758): avaliação de diferentes diluidores, concentração de glicerol e antioxidante catalase
(Universidade Federal do Pará, 2015-02-24) LEÃO, Danuza Leite; DOMINGUES, Sheyla Farhayldes Souza; http://lattes.cnpq.br/2794753357251149
The main objective of the present study was to establish an efficient semen cryopreservation protocol in Sapajus apella for maintaining sperm viability. For this, we compared the performance of TES-TRIS, CWS and ACP-118® extenders during the seminal coagulum dissolution and cooling. Then, in order to improve the sperm parameters, we also determined the glycerol concentration (3; 5 and 7%) as well as to evaluate the effect of catalase antioxidant (10 µg and 50 µg). Therefore, six adult males of S. apella from the National Primate Center were used. Semen was collected by electro-ejaculation with rectal probe after chemical restraint of animals with ketamine and xylazine hydrochloride. In the first phase of the project, the semen obtained was diluted in TES- TRIS, CWS and ACP®-118 extenders, kept in a water bath at 37 °C. After coagulum dissolution, the semen was cooled in the refrigerator at 4 °C for 90 minutes and evaluated after 28h for motility, vigor and plasma membrane integrity percentage before and after the cooling. ACP®-118 was the best extender to preserve the motility sperm and plasma membrane integrity after 28 hours of incubation. Based on these results, cryopreservation was performed by evaluation of different concentrations of glycerol (3, 5, and 7%). The cryopreserved sperm to 3% glycerol had better results. In the second project phase was performed S. apella semen cryopreservation in ACP®-118 extender supplemented or not with catalase antioxidant (10 µg/mL and 50 µg /mL). All treatments were effective in maintaining sperm parameters and was possible to recovery the post-thaw motility. The catalase 50 treatment was the best for maintenance of the vigor after cooling and plasma membrane integrity in post-thaw sperm. So, we concluded that ACP-118® extender can be efficiently used for S. apella semen cryopreservation added 3% glycerol, moreover, the addition of the catalase antioxidant showed beneficial effect during this process.
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)
Desenvolvimento do dimorfismo sexual em espécies de macacos-prego, gênero Cebus Erxleben, 1777 (Primates, Cebidae)
(Universidade Federal do Pará, 2008) MIRANDA, Cleuton Lima; SILVA JÚNIOR, José de Sousa e; http://lattes.cnpq.br/4998536658557008
The studies on sexual dimorphism available in the scientific literature have shown that Cebus apella is the most dimorphic species within the genus Cebus. However, it is worthy to say that several species of Cebus currently recognized were previously considered subspecies of C. apella, and were grouped as one single species in the studies mentioned above. This is not the case for the present report, in which I recognize six species previously assigned to C. apella. Additionally, most studies on sexual dimorphism in Cebus were based only on adult specimens, assuming that individuals exhibit no more growth after reaching complete permanent dentition. The lack of studies that take into account young or subadult specimens may result in a deficient knowledge about the origins of sexual dimorphism, because different ontogenetic processes may be related to the development of sexual dimorphism, all of them leading to similar results in adult specimens. Considering the issues mentioned above, the aims of the present study are to assess the sexual dimorphism in the skull and in the development degree of head tufts through different ontogenetic stages in six capuchin monkey species, all of them assigned to the subgenus Sapajus (Cebus apella, C. macrocephalus, C. libidinosus, C. cay, C. nigritus e C. robustus), and to evaluate the existence of taxonomic variation in the development and the amount of sexual dimorphism found. I examined 774 specimens housed in Brazilian institutions. I measured 20 cranial variables, examined 12 qualitative cranial characters, and established four character states for the development degree of the head tufts. I used the Student t Test with Bonferroni adjustment to evaluate the sexual dimorphism, and the Principal Component Analysis (PCA) followed by the Discriminant Analysis (DA) to test the statistical significance among the age classes herein recognized (infants, juveniles, subadults, and adults; the latter group was divided in AD1 and AD2 in C. apella). The results show that sexual differences in the skull of species of Sapajus can be found in subadult specimens (ca. 3.5 years old), of which the most conspicuous is the length of the upper canine. In this life stage, the sexual differences are not statistically significant. In adult specimens (ca. 5 years old), most cranial variables showed significant sexual dimorphism. The number and composition of the dimorphic variables varied among the different species included in this study. The species with more dimorphic variables were C. apella and C. robustus (N=15), followed by C. nigritus (N=13), C. libidinosus (N=10), C. cay (N=7), and C. macrocephalus (N=3). Different from previous studies available in the scientific literature, which states that sexual dimorphism in the skull of Cebus (Sapajus) arises in young specimens (ca. 27 months old), my results showed that a significant sexual dimorphism in this subgenus appears only in adult specimens. My results suggest that the heterocronic process of the hipermorphose rate is the main cause of the sexual dimorphism pattern exhibited by Sapajus. The species of capuchin monkeys included in this study exhibited different degree of development in the head tufts. In general, the development degree of this character in Cebus (Sapajus) is related to the age class to which the specimen belongs. Moreover, there is no sexual dimorphism in this character in C. cay, C. robustus, and C. nigritus. By contrast, female specimens of C. libidinosus appear to exhibit more developed head tuft than male specimens. Finally, my results suggest that the species of capuchin monkeys analyzed herein may have experienced different kinds or intensities of selective pressure relative to sexual dimorphism during their evolutionary history.
Acesso aberto (Open Access)
Discriminação simples auditiva em Macaco-prego (Cebus apella)
(Universidade Federal do Pará, 2009-03-11) MACHADO, Francisco José Freitas; SOUZA, Carlos Barbosa Alves de; http://lattes.cnpq.br/1264063598919201
The acquisition of generalized discriminative relational repertoires represents a complex discriminative capability in the interaction on any species with its environment, having, for much time, being considered to be exclusively human. There are few researches on this capability in non-human primates in the auditory modality, and even less about their multimodal discriminatory repertoire, which characterizes much of the complex discriminative human behavior. This study investigated the possibility of a capuchin monkey (Cebus apella) to learn to respond appropriately to different acoustic stimuli by the use of a simple discrimination procedure. The subject was exposed to five pairs acoustic stimuli: each pair was always composed of one sound with a predominance of high frequencies and another of low frequencies; one of them with a function of positive stimulus (S +) and the other of negative stimulus (S-). The criteria adopted for the presentation of a new pair of stimuli was the achievement of a rate of response for the (S-) equal of inferior more than 25% of the rate for the (S +), for five consecutive sessions. The subject reached the criteria for all five pairs of stimuli. The effects of learning set and the physical properties of the stimuli are discussed, as well as procedural differences in regard to previous studies. These results suggest the possibility of using capuchin monkey as an animal model in research on complex discriminative repertoires.
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.
Acesso aberto (Open Access)
Enriquecimento alimentar e cognitivo para o bem-estar em cativeiro
(Universidade Federal do Pará, 2012) COUTINHO, Paulo Henrique Módena; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075
When put an animal in captivity, we limit their actions, taking control of most of the variables that act on a restricted environment. These variables, although to remedy the basic needs of the animals has the potential to be highly predictable and therefore stress. Environmental enrichment can be one of the most important advances in animal health in captivity in recent times, raising the psychological and physiological parameters of well-being, suppressed by captivity. The main objective was to create and verify the effectiveness of an environmental enrichment equipment called "roulette" with the function of minimizing the harmful effects of the two captive capuchins, by increasing the time devoted to foraging activities, approaching its budget activities relevant to that of animals in the wild. The observations were made by instantaneous sampling method in five steps: 1) pre-intervention, 2) D5, 3) D10 4) D15 and 5) post-intervention, and subsequently compared longitudinally. The data demonstrate the effectiveness of roulette item enriching the environment, since the behaviors associated with the exploitation and displacement suffered increased over the intervention - with the exception of D10, which will soon be re-evaluated - keeping average frequency of foraging near than expected in free-living animals (Rímoli, 2001) still in the post-intervention observations, rather than the frequency of abnormal behavior or stereotyped.
Acesso aberto (Open Access)
Ensino de relações arbritárias e busca de simetria em Cebus apella
(Universidade Federal do Pará, 2010-02) FONSECA, Abraão Roberto; BARROS, Romariz da Silva; http://lattes.cnpq.br/7231331062174024
For some theorists, the lack of control over procedural variables has made difficult documenting equivalence classes in nonhuman subjects or human participants with developmental disabilities. The present research was divided in two experiments. The Experiment I aimed to evaluate the combined use of procedures such as “specific reinforcement”, “variations of S-“, “blocks of trials gradually smaller”, and “omission of previous S+ on the next trial block” in arbitrary relations training and symmetry test. A young male capuchin monkey (Cebus apella), Guga, served. The procedure comprised the following phases: pre-training, simple discrimination training, arbitrary relation training (A1B1 and A2B2), and symmetry test. The results show that Guga finished the arbitrary training in 39 sessions. The results of symmetry test show accurate performance for one relation and chance level accuracy for the other, with accurate performance in the first test trial for both relations. In Experiment II, two new relations (A3B3, A4B4) were added to the baseline (A1B1, A2B2). The results of the symmetry test for the new relations show accurate performance concerning to one relation and 75% of accuracy for the other. The present study encourages the development of procedures to reduce stimulus control incoherence and reinforces the possibility that the difficulty to document equivalence class formation in nonhumans relays on procedural variables.
Acesso aberto (Open Access)
Escola experimental de primatas
(2002-07) GALVÃO, Olavo de Faria; BARROS, Romariz da Silva; ROCHA, Aline Cardoso; MENDONÇA, Mariana Barreira; GOULART, Paulo Roney Kilpp
Equating, metaphorically, the terms "lab" and "school", this article presents an experimental research program aiming to develop procedures to build symbolic repertories in capuchin monkeys (Cebus apella). The metaphor "lab-school" arises from the similarity of the training procedures, used to teach discriminations or stimulus relations, to teaching programs used to introduce gradually more complex tasks. The challenge has been to keep the behavior of the "learners" under the control of the task properties, as programmed by the experimenter. Results document the acquisition of generalized identity and indicate the possibility of teaching more complex repertoires that are prerequisite for symbolic behavior and the possible application of the developed technology in teaching such repertoires to persons with difficulties to develop conventional symbolic functioning.
Acesso aberto (Open Access)
Escola experimental de primatas: análise da coerência entre pressupostos e práticas empíricas
(Universidade Federal do Pará, 2011-06-20) NAGAHAMA, Milena Monteiro; SOUZA, Carlos Barbosa Alves de; http://lattes.cnpq.br/1264063598919201
The development of animal models for the study of problems in human cognitive development requires, as a main factor, the existence of behavioral processes homology in repertories of the model and the humans. The Experimental School for Primates (ESP) has used the capuchin monkey (Cebus spp.) as an animal model to investigate the acquisition of generalized relational repertoires in humans. This study evaluated the empirical studies of the ESP in order to verify the consistency between their theoretical and empirical practices, especially the assumption of homology of behavioral processes among capuchin monkeys and humans. When analyzing a) the origin of the objectives and procedures of the studies (most come from animal studies), 2) if the expected results were achieved or not (in general, positive results in relation to the proposed objectives) and 3) if in studies of ESP the issue of animal model and/or applicability of the procedures used in studies to humans is discussed (it is not), it was noted that there are no empirical data supporting the homology proposal in theoretical proposition of the ESP. These results demonstrate that the scientific practice of ESP has advanced as basic research on the learning of generalized relational repertoires in capuchin monkeys, however, without providing transfer to study this phenomenon in humans. It is suggested that the way forward may be: 1) develop empirical studies that validate the homology of behavioral processes among some repertoires of human and capuchin monkeys, and 2) start implementing the findings of basic research of ESP in developing procedures for teaching relational repertoires for people with delayed cognitive development.