Artificial propagation of mutton snapper Lutjanus analis, a new candidate marine fish species for aquaculture.

摘要

15 juvenile mutton snappers were caught off Lee Stocking Island, Bahamas, during May-August 1992, and were matured in flow-through seawater tanks. On 31 May 1995, a female with a mean oocyte diameter of 382μm was injected with 500 IU/kg body weightHCG followed, 24 h later, by a 2nd injection of 1000 IU/kg. At the time of the 2nd injection, 3 males were injected with 500 IU/kg HCG. Spawning occurred 33 h after the 1st injection, with a total of 534 781 eggs released. Fertilization rate was 75.7%,while average diameter of fertilized eggs was 783μm. Embryos were stocked in a 30-m3 outdoor tank at a density of 10.5/litre. On day 2 post-hatching, larval density was 8.61 larvae/litre and average notochord length was 2.6 mm. Larvae were fed ss-type rotifers up to day 28 after hatching, Artemia nauplii from day 7-38, and artificial diets (52-48% protein) from day 24-38. 38 days after hatching, fish averaged 0.308 g body weight and 22.2 mm standard length. Survival (from day 2) was 14.3%, with a totalof 36 900 post-metamorphic juveniles produced. On day 97 after hatching, 1390 hatchery-reared juveniles (average body weight = 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 days, fish averaged 140.8 g, with a survival rate of 97.8% and a feed conversion ratio of 1.2.