Morphophysiological elements involved in early and long gonadal maturation in fish and biotechnological applications

• Grant number: 21/03739-3
• Support type: Regular Research Grants
• Duration: January 01, 2022 - December 31, 2024
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Cooperation agreement: Czech Science Foundation (GACR)
• Principal researcher: Rosicleire Veríssimo Silveira
• Grantee: Rosicleire Veríssimo Silveira
• Principal researcher abroad: Martin Psenicka
• Institution abroad: University of South Bohemia in Ceske Budejovice (USB), Czech Republic
• Home Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil
• Assoc. researchers: Alexandre Ninhaus Silveira ; Fernanda de Mello ; Rafael Henrique Nóbrega ; Renata Guimarães Moreira Whitton
• Associated scholarship(s): 22/05616-9 - To evaluate the effects of different temperatures in the first gonadal maturation of Astyanax altiparanae, a Neotropical species with short maturation cycle, BP.TT

Abstract

The first gonadal maturation in teleosts is under multifactorial control of neurohormones, pituitary gonadotropins, as well as a number of gonadal hormones including sex steroids and growth factors. The speed of this process varies among vertebrates and is controlled by extrinsic and intrinsic regulations. There are species such as Nothobranchius furzeri (Actinopterygii), which is considered the fastest maturing known vertebrate taking two weeks until first reproduction, whereas other species as Salmo salar (Actinopterygii) take 3 years until first reproduction. In general, cultivation of long-maturing species has a high cost in the aquaculture until the first reproduction takes place. Therefore development of strategies to shorten generation time has become necessary for a more efficient production. Thus, this project aims to evaluate extrinsic and intrinsic factors that could accelerate the first gonadal maturation of Astyanax altiparanae, a well established Neotropical model. Specimens of A. altiparanae will be reared at different temperatures, and gonadal histology, pituitary gonadotropin expression and plasma steroid levels will be assessed. Based on the treatment that induced rapid maturation, transcriptome analyses (gonad and pituitary) will be carried out to identify candidate genes involved in the acceleration of the first gonadal maturation. Subsequently, we propose the development of biotechnological strategies to accelerate gonadal maturation of economically and ecologically important species such as tambaqui, Colossoma macropomum (Brazil) and sturgeons as Acipenser ruthenus (Czech Republic). These strategies consist of developing a 3D testicular organoid to drive in vitro sperm maturation and xenografting pieces of immature testes from long maturing species into A. altiparanae reared at different temperatures. Altogether this project will contribute to basic knowledge on fish gonadal maturation and developing strategies to accelerate gonadal maturation in species with economical and ecological relevance in Brazil and Czech Republic. (AU)