Growth Performance of Goldenfin Pompano at Two Stocking Densities in Near-Shore Ocean Cages at Hainan, China
Region: Northeast AsiaDownload
Goldenfin pompano growth performance in coastal cages was evaluated from juvenile to market size at two stocking densities using the ASA LVHD cage production model and ASA extruded, marine fish feeds. The cage trial was conducted in Xincun Bay at Ling Shui, Hainan, China. Pompano were stocked in 8.0-m3 cages at densities of 250 fish per m3 (2,000 fish per cage) and 375 fish per m3 (3,000 fish per cage), with three replicates of each stocking density. Juvenile pompano were fed to satiation daily with a 47% crude protein and 15% crude fat feed (47/15) to fish size 25 g, and with a 43% crude protein and 12% crude fat feed (43/12) from fish size >25 g. Both feeds were fed in extruded, floating pellet form. Pompano stocked at 250/m3 grew from 5 g to 389 g in 157 days of feeding, while pompano stocked at 375/m3 grew from 5 g to 385 g in the same period. Fish growth at the two densities was not significantly different (P>0.05). Gross production per m3 of cage volume at harvest was 88.3 kg at the 250/m3 stocking density and 117.3 kg at the 375/m3 stocking density. Gross production at harvest was significantly different (P<0.05) for the two stocking densities. Average FCR with the combination of 47/15 and 43/12 feeds was 2.11:1 for fish at the 250/m3 and 2.26:1 for fish at the 375/m3 stocking density. Average fish survival was 90.8% at the 250/m3 density and 81.2% at the 375/m3 density. Fish survival and FCR were both significantly different (P<0.05) for the two stocking densities. Net economic return and return on investment (ROI) were RMB 2,806/cage (RMB 351/m3) and 24.8%, respectively, for fish stocked at 250/m3, and RMB 3,161/cage (RMB 395/m3) and 20.3%, respectively, for fish stocked at 375/m3. Neither net economic return nor ROI were significantly different (P>0.05) at the prevailing market price of RMB 20/kg for goldenfin pompano. Feed cost per kg of fish growth with the ASA feeds was RMB 10.13 for fish stocked at 250/m3 and RMB 10.85 for fish stocked at 350/m3. Results of the trial indicate that goldenfin pompano can be cultured at high density in LVHD ocean cages, but that FCR and fish survival are negatively impacted at the higher density. Fish growth performance was good at both densities and did not decline, even when carrying capacity in the high density cages reached 117 kg/m3.