IBBEA   24401
INSTITUTO DE BIODIVERSIDAD Y BIOLOGIA EXPERIMENTAL Y APLICADA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Neuroendocrine regulation of social and reproductive behavior in a cichlid fish.
Autor/es:
PANDOLFI MATIAS; MARTIN RAMALLO; MORANDINI LEONEL
Lugar:
Montevideo
Reunión:
Conferencia; II Meeting of Neuroetholgy in the Southern Cone; 2016
Institución organizadora:
ISSN
Resumen:
In social animals with hierarchal dominance systems interactions with conspecifics and hierarchal position can greatly affect an individual´s behavior, physiology and reproductive success. Our experimental model, Cichlasoma dimerus, is a serially-monogamous Neotropical cichlid fish with a hierarchical social system, established and sustained through agonistic interactions. We aimed to describe C. dimerus social structure and its association with hormonal profiles and testicular cellular composition. We recorded and quantified agonistic interactions from the territorial pair and the lowest ranked male of stable social groups. Plasma levels of 11-ketotestosterone (11-KT), testosterone, 17β-estradiol (E2) and cortisol were measured by ELISA. Results show that territorial pairs cooperatively guarded the territory, but rarely attacked in synchrony. Territorial (T) males had higher testosterone and 11-KT levels than non-territorial (NT) males, while E2 and an index of its metabolization from testosterone were higher in non-territorial males. No difference was observed in cortisol levels. 11-KT and an index of the conversion of testosterone to 11-KT, positively correlated with the frequency of aggressiveness, while E2 showed the opposite pattern. T males had a higher gonadosomatic index than NT males. The quantification of testicular cellular types revealed that the percentage of spermatocytes and spermatids was higher in NT males, while T males showed a greater percentage of spermatozoa. Thus, C. dimerus male social position within a stable hierarchy is associated with distinct behaviors, steroid levels and testicular degree of development.