Synchronization of the ovarian maturation process in pacu (Piaractus mesopotamicus)

• Grant number: 10/05286-1
• Support Opportunities: Regular Research Grants
• Start date: June 01, 2010
• End date: November 30, 2012
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Fausto Foresti
• Grantee: Fausto Foresti
• Host Institution: Centro de Aquicultura (CAUNESP). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated researchers: Sergio Ricardo Batlouni

Abstract

In spite of being one of the most exploited fish species in Brazil, the pacu (Piaractus mesopotamicus) still presents some obstacles concerning its hormonally-induced reproduction, specially in what regards the occurrence of females that do not release their oocytes after treatment. In this context, the intense asynchrony on the process of ovary maturation among individuals must be considered, since because of that immature females may be mistakenly chosen, and/or the excessive management searching for mature fish may induce a regression process throughout the broodstock. Therefore, to standardize a safety protocol (less empirical and more scientific) for choosing pacu females in fact "mature" for hormonal induction, the aim of this study is to evaluate the possibility of synchronization of ovarian maturation process in a pacu broodstock, using GnRH (Gonadotropin-releasing hormone) slow-release implants. The success of the application of this protocol will be based on the comparison of the ovarian maturation stage between treated and control groups 30 days after implant administration. Besides, the serum levels of gonadal steroids (progesterone, estradiol and testosterone) and the growth hormone (GH) gene expression levels will be monitored in the pituitaries of control and treated animals. Complementarily, for the male breeders, the sperm quality (cytological and DNA) will be assessed in three periods during the breeding season (October, November, December) aiming to detect possible interference of the time period of male gamete collection on the quality fingerlings production. In this way, in this proposal we intend to introduce the use of a protocol for ovarian maturation synchronization for pacu broodstocks, ensuring the safety selection of mature specimens in a foreseeable and suitable time for the hormonally induced reproduction. (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)

KURADOMI, RAFAEL YUTAKA; FORESTI, FAUSTO; BATLOUNI, SERGIO RICARDO. The effects of sGnRHa implants on Piaractus mesopotamicus female breeders. An approach addressed to aquaculture. AQUACULTURE INTERNATIONAL, v. 25, n. 6, p. 2259-2273, DEC 2017. (10/05286-1, 10/00825-1)

KURADOMI, RAFAEL Y.; DE SOUZA, THIAGO G.; FORESTI, FAUSTO; SCHULZ, RUDIGER W.; BOGERD, JAN; MOREIRA, RENATA G.; FURLAN, LUIZ R.; ALMEIDA, EDUARDO A.; MASCHIO, LUCILENE R.; BATLOUNI, SERGIO R.. Effects of re-stripping on the seminal characteristics of pacu (Piaractus mesopotamicus) during the breeding season. General and Comparative Endocrinology, v. 225, p. 162-173, JAN 1 2016. (10/05286-1, 10/00825-1)