Efeito do enriquecimento ambiental no comportamento e no cortisol fecal de Callithrix penicillata (É. Geoffroy, 1812) de cativeiro

Abstract

Non-human primates are often used in behavioral studies and in biomedical research as a model mainly because their phylogenic proximity to human beings. However, the use of non-human primates in researches implies in many ethical issues, including the captivity conditions and the potential aspects of the procedures that may cause pain, injuries and stress which can interfere with their welfare. The present research intended to analyze the behavioral and endocrine responses of six males and six females of captive black-tuffed marmosets (Callithrix penicillata) to a feeding (tube) and a visual isolation (barrier) environmental enrichment techniques. The animals belong to the colony maintained by Centro de Biologia da Reprodução of Universidade Federal de Juiz de Fora, in Juiz de Fora, Minas Gerais state, in Brazil. The behavior and hormonal data were collected before, during and after the exposure to environmental enrichment. The hormonal analysis of fecal cortisol was performed in the Laboratorio de Dosagens Hormonais of the Universidade Federal do Rio Grande do Norte. During the exposure to the feeding enrichment technique – FASE II, it was observed a decrease in movement and in ingestion of the regular diet by the animals. Besides, in this experiment, the male marmosets were more reactive than the females and no significant differences on cortisol levels were detected. Using the social enrichment (a visual barrier between the cages), it was verified the existence of conflicts between close same-sex animals, which decreased cortisol when the barrier was used. In this case, the marmoset females were more reactive to the enrichment probably because they compete to reproductive as a consequence of social dominance. For males the isolation seems to be a stressful situation since they increase cortisol on this situation.