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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‐m3 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‐m3 recirculating seawater tanks (695 fish/tank; 48 fish/m3) 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.

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The objectives of this study were to determine the effects of the dietary docosahexaenoic acid (DHA) to arachidonic acid (ARA) ratio on the survival, growth, hypersaline stress resistance and tissue composition of black sea bass larvae raised from ¢rst feeding to metamorphic stages. Larvae were fed enriched rotifers Brachionus rotundiformis and Artemia nauplii containing two levels of DHA (0% and10% total fatty acids 5 TFA) in conjunction with three levels of ARA (0%, 3% and 6% TFA). On d24ph, larvae fed the 10:6 (DHA:ARA) treatment showed signi¢cantly (Po0.05) higher survival (62.3%) than larvae fed 0:0 (DHA:ARA) (27.4%). Notochord length and dry weight were also signi¢cantly (Po0.05) greater in the 10:6 (DHA:ARA) treatment (8.65 mm, 2.14 mg) than in the 0:0 (DHA:ARA) (7.7 mm, 1.65 mg) treatment. During hypersaline (65 g L À 1 ) challenge, no signi¢cant di¡erences (P40.05) were observed in the median survival time (ST50) between larvae fed 10% DHA (ST50 525.6 min) and larvae fed 0% DHA (ST50 518.2 min). The results suggested that black sea bass larvae fed prey containing 10% DHAwith increasing ARA within the range of 0^6% showed improved growth and survival from ¢rst feeding through metamorphic stages.