Allometric Growth in Hatchery‐Reared Gilthead Seabream

Abstract

AbstractMorphological development and allometric growth were investigated in the gilthead seabream Sparus aurata during larval development until the end of the weaning period on day 41. Fertilized eggs had a diameter of 1.01 ± 0.02 mm (mean ± SE) and a lipid vesicle diameter of 0.227 ± 0.021 mm. Mean total length (TL) was 2.68 ± 0.04 mm for newly hatched larvae and 3.57 ± 0.09 mm at the onset of feeding (4 d after hatching [DAH]). At 10 DAH, initial swim bladder inflation occurred, mean TL was 4.19 ± 0.08 mm, and notochord length (NL) was 4.00 ± 0.07 mm. At 16 DAH, the swim bladder became more elongated, TL was 5.13 ± 0.09 mm, and NL was 4.94 ± 0.07 mm. Notochord flexion occurred at 6.46 ± 0.11 mm TL on 23 DAH, and the complement of the flexion occurred at 8.67 ± 0.109 mm TL on 35 DAH. At the end of the weaning period (at 41 DAH), larvae were 10.85 ± 0.116 mm TL. The majority of all allometric changes from the inflection point were expressed during the larval stage and integrated with the metamorphosis stage. Inflections in body proportion changes occurred mainly at 4.19 and 7.04 mm TL, corresponding to initial swim bladder inflation and the notochord flexion period, respectively.