| Title: | GnRHa implants and size pairing effects on plasma and cephalic secretion sex steroids in Arapaima gigas |
| Author(s): | Torati LS; Taylor JF; Mesquita PEC; Migaud H; |
| Address: | "EMBRAPA Fisheries and Aquaculture, 77022-000 Palmas, TO, Brazil; Institute of Aquaculture, University of Stirling, Stirling, FK9 4LA Scotland, UK. Electronic address: lucas.torati@embrapa.br. Institute of Aquaculture, University of Stirling, Stirling, FK9 4LA Scotland, UK. Electronic address: j.f.taylor@stir.ac.uk. Center of Research in Aquaculture Rodolpho von Ihering-CPA/DNOCS - Ombreira Direita, s/n. Pentecoste-CE, Brazil. Electronic address: pedro_mesquita@uol.com.br. Institute of Aquaculture, University of Stirling, Stirling, FK9 4LA Scotland, UK. Electronic address: herve.migaud@stir.ac.uk" |
| DOI: | 10.1016/j.ygcen.2020.113614 |
| ISSN/ISBN: | 1095-6840 (Electronic) 0016-6480 (Linking) |
| Abstract: | "Arapaima gigas, one of the world's largest freshwater fish, is considered an emerging species for aquaculture development in Brazil given its high growth rate and meat quality. However, the lack of reproductive control in captivity has limited the expansion of Arapaima farming. This study aimed to test the effects of hormonal induction using mGnRHa implants and size pairing on broodstock reproduction through the analyses of sex steroids. To do so, broodstock of different sizes (large, small or mixed) were paired and implanted. Plasma and cephalic secretion profiles of testosterone (T), 11-ketotestosterone (11-KT) and 17beta-oestradiol (E(2)) were analysed. Compared to control (non-implanted), implanted broodstock showed a significant increase in plasma 11-KT (large and small males) and T (large and mixed females) post GnRHa implantation. In females, a significant increase in plasma T levels was shown, however, E(2) remained unchanged after implantation. Despite the lack of clear spawning induction, this study showed the potency of GnRHa on sex steroid production regardless of pairing groups. Interestingly, significant correlations between blood plasma and cephalic secretion levels of 11-KT in males and T in females were observed, indicating the possible release of pheromones through the cephalic canals of A. gigas" |
| Keywords: | Animals Aquaculture Brazil Female Fishes Gonadal Steroid Hormones/*analysis Gonadotropin-Releasing Hormone/*pharmacology Male Plasma/drug effects/*metabolism *Reproduction Hormonal induction Lateral line Pheromones Pirarucu Reproduction Sex steroids; |
| Notes: | "MedlineTorati, Lucas S Taylor, John F Mesquita, Pedro E C Migaud, Herve eng Research Support, Non-U.S. Gov't 2020/09/21 Gen Comp Endocrinol. 2020 Dec 1; 299:113614. doi: 10.1016/j.ygcen.2020.113614. Epub 2020 Sep 17" |
