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| Author(s): |
Olívia de Mendonça Furtado
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Psicologia (IP/SBD) |
| Defense date: | 2012-08-01 |
| Examining board members: |
Patricia Izar Mauro;
Marie Odile Monier Chelini;
Fernando Ribeiro Gomes;
Briseida Dogo de Resende;
Michele Pereira Verderane
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| Advisor: | Patricia Izar Mauro |
| Abstract | |
Stress physiology studies are of fundamental importance for the area of behavioral endocrinology and for projects that aim to promote the wellbeing of captive animals. When the subjects of those researches are wild animals, it is possible to investigate which environmental or social stimuli constitute stressors for this taxon. Little is known in this regard about capuchin monkeys (Sapajus genus), a neotropical primate that are constantly kept in zoos, breeders and others captive environments. A better comprehension of the stressors agents in this genus can contribute for the wellbeing of those captive individuals. Therefore this study aimed: 1) to investigate through the variation of glucocorticoids levels (GCs hormones related to stress), which environmental and behavioral events are perceived by wild capuchin monkeys as stressful; 2) access the possibility of defining basal fecal glucocorticoids metabolites levels (MFGs measuring GCs in feces is a non-invasive form of evaluate those hormones), as reference values, for the Sapajus genus; and 3) validate the experimental protocol of fecal hormones extraction and dosage. For the first two objectives, measures of fecal glucocorticoids metabolites, behavioral and environmental data of two wild populations of capuchin monkeys were taken. One in the Carlos Botelho State Park/São Paulo (PECB) and the other in Boa Vistas Farm/Piauí (FBV). For the experimental protocol validation an ACTH and dexamethasone challenge was executed with captive capuchin monkeys. Generalized Linear Mixed Models (MLGM) analysis showed a significant difference between basal levels of MFGs of the two populations, being the FBV the one with higher values. For that population there was also an effect of fruit availability in the habitat, frequency of encounters with other animals species and copulations in the mensal variation of the MFGs basal levels. There was no significant effect of the studied variables in the mensal basal levels variation of MFGs in the PECB population. The individual analyses showed that agonistic interactions among group members were the major cause of MFGs\' peaks in the studied subjects. Other major factors were females in proceptive period and copulations, that caused peaks not only in adult males, but also in juvenile males and the females themselves. The ACTH and dexamethasone challenge results validated the experimental protocol of hormones extraction and dosage. The obtained results are in agreement with previous researches that reveled marked differences in the social system of the two populations, specially in females social relationships that varied in accordance with the two areas ecological differences. The results also suggested that it is not possible to define reference values of MFGs\' basal levels for the Sapajus genus once the two populations are significantly different in this aspect. This work is just the beginning of a long endeavor to comprehend stress in wild capuchin monkeys, nevertheless it presents the first glimpse to the understanding of the natural stressors for those animals and how they impact the MFGs\' levels (AU) | |