Free and total testosterone levels in field males of Octodon degus (Rodentia, Octodontidae): accuracy of the hormonal regulation of behavior

Soto-Gamboa, M

Abstract

Animals exhibit continuous seasonal changes in physiological, morphological and behavioral traits associated to their natural annual cycles. One of the most important changes in the organism occurs at the initiation of breeding season. In males these changes include activation of spermatogenesis, enhance of sexual secondary characters and an increase of aggressiveness. All of theses changes are basically regulated by testosterone, but the physiological basis of this testosterone regulation and the effective hormone proportion that acts in target tissues are unknown. In this work I evaluated the relationship between total testosterone, free testosterone associated to aggressive behavior in wild males of Octodon degus. I compared hormonal levels and aggressive behavior during pre, middle and post breeding periods. Results showed that behavioral aggressiveness was correlated with both total and free testosterone in June, during the beginning of breeding season, but not at other times. Results also indicated a lack of relationship between free and total testosterone in most of breeding period. I discuss the importance of this behavior-hormonal regulation (determined by free testosterone) and the physiological importance of this mechanism to the organism

Más información

Título según WOS: Free and total testosterone levels in field males of Octodon degus (Rodentia, Octodontidae): accuracy of the hormonal regulation of behavior
Título según SCIELO: Free and total testosterone levels in field males of Octodon degus (Rodentia, Octodontidae): accuracy of the hormonal regulation of behavior
Título de la Revista: Revista chilena de historia natural
Volumen: 78
Número: 2
Editorial: Sociedad de Biología de Chile
Fecha de publicación: 2005
Página de inicio: 229
Página final: 238
Idioma: English
DOI:

10.4067/S0716-078X2005000200006

Notas: ISI, SCIELO