Early Life History of Cultured Common Dentex (Dentex dentex L. 1758)


Abstract: The early life history of common dentex (Dentex dentex L. 1758) was investigated under culture conditions. The percentage of fertilized buoyant eggs was generally high, between 80 and 85%. Egg diameters ranged from 0.938 to 1.089 mm. Larval development, growth, and some morphological changes were described from day 0 to day 32. Larvae were reared intensively in 6 m^3 tank under a constant photoperiod (24 h light), and fed initially on rotifers, followed by Artemia nauplii and Artemia metanauplii. A green water technique was applied using Nannochloropsis sp., Chorella sp., and Isochrysis sp. at a density of 150,000-200,000 cells ml^{-1}. First feeding began on day 6. Larvae completed yolk absorption on day 8 after hatching at 136 ºC cumulative temperature (day/degrees). Swimbladder inflation occurred between day 5 and day 7 post-hatching. Notochord flexion started on day 23 at 7.01 mm total length. Metamorphosis from larval to juvenile stage occurred between days 23 and 32 post-hatching at a mean total length of 12.7 mm.

Keywords: Dentex dentex, common dentex, larval development, metamorphosis, morphology

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