title: Aggressive behavior and reproductive physiology in females of the social cichlid fish Cichlasoma dimerus.
abstract: 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 hypothalamus-pituitary-gonads axis during reproduction in a species with highly organized breeding activity.
authors.affiliation: Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EHA), Buenos Aires, Argentina.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Tubert
authors.forename: Fabiana
authors.initials: F
authors.lastname: Lo Nostro
authors.forename: Virginia
authors.initials: V
authors.lastname: Villafañe
authors.forename: Matías
authors.initials: M
authors.lastname: Pandolfi
mesh_terms: D000374:Aggression / Q000523:psychology*; D000818:Animals; D001921:Brain / Q000166:cytology; D023681:Cichlids / Q000502:physiology*; D004958:Estradiol / Q000097:blood; D005260:Female; D037201:Follicle Stimulating Hormone, beta Subunit / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology; D006854:Hydrocortisone / Q000097:blood; D037101:Luteinizing Hormone, beta Subunit / Q000378:metabolism; D008297:Male; D009474:Neurons / Q000166:cytology / Q000502:physiology; D010053:Ovary / Q000033:anatomy & histology; D010902:Pituitary Gland / Q000378:metabolism; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives; D055703:Reproductive Physiological Phenomena; D013739:Testosterone / Q000097:blood
chemical_list: D037201:Follicle Stimulating Hormone, beta Subunit; D037101:Luteinizing Hormone, beta Subunit; C448022:gonadotropin-releasing hormone-III; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D004958:Estradiol; D011761:Pyrrolidonecarboxylic Acid; D006854:Hydrocortisone