Hormonal profile during the reproductive cycle and artificial reproduction of dusky grouper (Epinephelus marginatus) (Teleostei: Serranidae) in captivity

• Grant number: 11/24074-8
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): June 01, 2012
• Effective date (End): August 31, 2014
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Renata Guimarães Moreira Whitton
• Grantee: Jandyr de Almeida Rodrigues Filho
• Host Institution: Centro de Aquicultura (CAUNESP). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

The hypothalamic-pituitary-gonadal axis directly controls reproduction in vertebrates. This command begins with the synthesis and release of gonadotropin-releasing hormone (GnRH) from the hypothalamus which stimulates the anterior pituitary to synthesize and release the follicle stimulating hormone (FSH) and luteinizing hormone (LH) in the blood. Then, FSH and LH stimulate the production of gonadal steroids gonad. These gonadal steroids, testosterone (T), 17 b -estradiol (E2), 11-cetotestosterona (11-KT), 17 -20 a b-dihydroxy-4-pregnen-3-one (17-20 a b-DHP), promote the development, proliferation, maturation and release of gametes of animals. However, many fish of commercial interest in aquaculture, including the dusky grouper, Epinephelus marginatus exhibit reproductive disorders due to confinement, similar to most wild animals when kept in captivity. These disorders probably results from the combination of the stress induced by captivity and the absence of the natural environment for spawning, directly influencing the hypothalamic - pituitary - gonads axis. Considering the the endocrine control of reproduction, the focus of this work is to study the profile of some hormones that modulate reproduction of dusky grouper: 1) during the reproductive cycle, 2) and during artificial induced to spawning, with different hormone preparations. The plasma concentrations of gonadotropins (FSH and LH), the gonadal steroids (E2, T, 11 KT and 17 a-OHP) will be analyzed and the oocyte growth will be monitored in E. marginatus females in captivity, considering females with different egg diameter. Beyond generating knowledge about the physiological basis involved in the endocrine reproductive axis in females in captivity and during artificial reproduction, this work will be important to support the protocol of induced spawning, to be applied in the conservation of this endangered species. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RODRIGUES-FILHO, J. A.; ARAUJO, B. C.; MELLO, P. H.; GARCIA, C. E. O.; SILVA, V. F. D.; LI, W.; LEVAVI-SIVAN, B.; MOREIRA, R. G.. Hormonal profile during the reproductive cycle and induced breeding of the dusky grouper Epinephelus marginatus (Teleostei: Serranidae) in captivity. Aquaculture, v. 566, p. 11-pg., 2022-12-22. (11/24074-8)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

RODRIGUES FILHO, Jandyr de Almeida. Perfil hormonal durante o ciclo reprodutivo e reprodução induzida da garoupa verdadeira (Epinephelus marginatus) (Teleostei: Serranidae) em cativeiro. 2016. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal Jaboticabal.