Submitted to: Global Aquaculture Advocate
Publication Type: Trade journal
Publication Acceptance Date: 10/31/2005
Publication Date: 10/31/2005
Citation: Riley, K., Riche, M.A. 2005. Florida study achieves tank spawning of southern flounder on pelleted feed. Global Aquaculture Advocate. 8(5):52-53. Interpretive Summary:
Technical Abstract: Worldwide interest in the culture of various flatfish species has developed because of continuing declines in wild stocks combined with a consistent high demand and market value. The southern flounder, Paralichthys lethostigma, is a high-value species that has been considered a good candidate for aquaculture because of its tolerance to a range of salinities, temperatures and culture conditions; however, a bottleneck exists with respect to the production high quality gametes, larvae and fingerlings. To support the development of commercial growout operations, simple and reliable hatchery techniques for southern flounder are needed. The goal of this study was to evaluate gamete quality and fertilization success for spawns collected from natural and hormone-induced tank spawning of fish fed a diet of thawed fish or a practical growout diet. Broodstock were fed daily a diet of thawed fish or a commercially produced 12-mm floating pelleted diet (Melick Aquafeed; 50% protein, 10% lipid). Egg production was highly variable among spawns. For the population of broodstock fed thawed fish, egg production ranged from 6,000 to 181,000 eggs and fertilization rates were 38 ± 30%. For the broodstock fed the commercial diet, egg production ranged from 9,000 to 188,000 eggs and fertilization rates were 40 ± 38%. Although egg fatty acid profiles were not different in terms of DHA, EPA, or Arachidonic Acid, pellet fed fish produced on average higher quality and higher quantities of eggs. This study demonstrates that broodstock fed a pelleted diet will spawn and produce viable eggs and larvae.