W.O. Watanabe, E.P. Ellis, S.C. Ellis, J. Chaves, C. Manfredi, R.W. Hagood, M. Sparsis, S. Arneson-1998
Journal of the World Aquaculture Society, 29(2): 176-187
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 micrometer 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 micrometer. 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 d1-d28ph, Artemia nauplii from d7-d38ph, 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 sate 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.
(Caribbean Marine Research Center, 805 East 46th Place, Vero Beach, Florida 32963 USA)