INVESTIGADORES
TUBERT Cecilia
artículos
Título:
Aggressive behavior and reproductive physiology in females of the social cichlid fish Cichlasoma dimerus
Autor/es:
CECILIA TUBERT; FABIANA LO NOSTRO; M. VIRGINIA VILLAFAÑE; MATIAS PANDOLFI
Revista:
PHYSIOLOGY AND BEHAVIOR
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Houston Texas; Año: 2012 p. 193 - 200
ISSN:
0031-9384
Resumen:
The South American cichlid fish Cichlasoma dimerus is a freshwater species that presents social hierarchies, a
highly organized breeding activity, biparental care and a high frequency of spawning. Spawning is followed
by a period of parental care (about 20 days in aquaria conditions) during which the cooperative pair takes
care of the eggs, both by fanning them and by removing dead ones. The different spawning events in the reproductive
period were classified as female reproductive stages which can be subdivided in four phases,
according to their offspring degree of development: (1) female with prespawning activity (day 0), (2) female
with eggs (day 1 after fertilization), (3) female with hatched larvae (day 3 after fertilization) and (4) female
with swimming larvae (FSL, day 8 after fertilization). In Perciform species gonadotropin-releasing hormone
type-3 (GnRH3) neurons are associated with the olfactory bulbs acting as a potent neuromodulator of reproductive
behaviors in males. The aim of this study is to characterize the GnRH3 neuronal system in females of
C. dimerus in relation with aggressive behavior and reproductive physiology during different phases of the reproductive
period. Females with prespawning activity were the most aggressive ones showing GnRH-3 neurons
with bigger nuclear and somatic area and higher optical density than the others. They also presented the
highest levels of plasma androgen and estradiol and maximum gonadosomatic indexes. These results provide
information about the regulation and functioning of hypothalamuspituitarygonads axis during reproduction
in a species with highly organized breeding activity.