Artificial Propagation of Mutton Snapper <i>Lutjanus analis, A</i> New Candidate Marine Fish Species for Aquaculture

Abstract

Abstract Wild‐caught mutton snapper Lutjanus analis , a high‐value marine food fish species, matured in flow‐through seawater (36 g/L) tanks after 3 yr in captivity. On 31 May 1995, a female with a mean oocyte diameter of 382 μm was injected with human chorionic gonadotropin (HCG) (500 IU/kg body wt.) followed 24 h later by a second injection (1,000 IU/kg body wt.). At the time of the second injection, three males were injected with HCG (500 IU/ kg body wt.). Voluntary spawning occurred 33 h after the first injection, with a total of 534, 781 eggs released. Fertilization rate was 75.7%, while average diameter of fertilized eggs was 783 μm. Embryos were stocked in a 30‐m 3 outdoor tank at a density of 10.5/L. On day 2 post‐hatching (d2ph), larval density was 8.61 larvae/L, and average notochord length was 2.6 mm. Larvae were fed ss‐type rotifers from dl‐d28ph, Artemia nauplii from 0–08ph, and artificial diets (52–48% protein) from d24‐d38ph. On d38ph, fish averaged 0.308 g and 22.2 mm standard length. Survival (from d2ph) was 14.3%, with a total of 36,900 post‐metamorphic juveniles produced. On d97ph, 1,390 hatchery‐reared juveniles (avg. wt. = 10.5 g) were stocked into two 14.5‐m 3 recirculating seawater tanks (695 fish/tank; 48 fish/m 3 ) and fed a 56% protein pellet. After 168 d, fish averaged 140.8 g, with a survival rate of 97.8% and a feed conversion ratio (dry wt./wet wt.) of 1.2. These preliminary results reveal the mutton snapper to be a prime, new candidate species for commercial cultivation.