Abstract
The artificial propagation of the wild fat snook, Centropomus parallelus, was investigated in laboratory. This study tested a protocol for spawning induction using human Chorionic Gonadotropin (hCG) and an incubation system with different egg densities. Females were injected with 1,100 IU of hCG/Kg, and males with 500 IU/Kg. Fish were held in tanks of 160L capacity, with two males and one female. Temperature was 23,9-27,3oC and salinity was 35. A total of 19 hormonal inductions were carried out, resulting in 7 natural spawnings and 12 with artificial fertilization. The best fertilization and hatching rates were obtained when ovulation occurred at 32-36 h post-induction (816-972 hour-degrees). The average relative fecundity was 373.000 eggs/Kg of body weight. Viable larvae were obtained in 43% of the natural spawning trials, and in 58% of the artificial spawning trials. In the incubation system, density was 553 to 1,705 eggs/L, using 9 incubators with 37L capacity inside a 2,000-L tank. Eggs were maintained in an open flow-through system with continuous aeration. After 19 hours, the number of hatched larvae was 305 to 850/L. Spearman test showed no correlation between egg density and hatched larvae (P>0.05). The average hatching rate was 52%.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have