Spawning quality obtained in greater amberjack (Seriola dumerili) through GnRHa inductions by injections or implants

Abstract

Aquaculture development in marine fish is mainly based on a few species, therefore diversification is a priority. The aim of the present study was to obtain spawns of great amberjack (Seriola dumerili) by induction with gonadotropin releasing hormone analogue (GnRHa) injection or implant and determine their effects on eggs quality and economic performance. Wild sub-adult were captured and tagged individually, and kept in 40 m3 tanks during 2 years. A total of 6 mature fish (sex ratio 50%) per treatment were induced with 20 µg kg−1 and 40 µg kg−1 of GnRHa through injection and implants respectively. The spawn quality showed significant differences (P<0,05) between injection and implant treatments, in terms of viable eggs (%), hatched larvae (%), and larvae survival (%, 3dph). The injection treatment showed better economic performance in all evaluated parameters, but significant differences were displayed only in price of 1000 eggs/Kg/spawn.