EVELOPMENT OF EMBRYOS AND LARVAE METAMORPHOSIS OF NEMO ANEMONEFISH AMPHIPRION OCELLARIS CUVIER 1830 IN THE LABORATORY

Abstract

Nemo Anemonefish (Amphiprion ocellaris) embryos had been taken well care by parental fish. The embryos  developed normally in 7 - 8 days in incubated temperatures 27 ± 1 ⁰C; salinity 34 – 35 ppt; pH ranged from 8.1 to 8.3; O₂ > 5 mg/l; NH₃ + < 0.1 mg/l and NO₂- < 0.05 mg/l. The study had been carried out from January 2009 to August 2009.

The eggs were sticky and looked like capsules with lengths of 2.59 ± 0.14 mm and widths of 0.93 ± 0.07 mm. Ten hours after spawning the embryos developed into Blastula. Nineteen hours after spawning, the  embryos developed into Gastrula. After 38 hours, the hearts were clearly observed beating at a rate of 78 times per minute, and the iris was visible. On the fifth-day the pectoral, dorsal and ventral fin folds were well defined. On the sixth-day the gills were more apparent, vestiges of the gill rakers were visible, the mouth  could be distinguished, and the anus could be seen. On the seventh-day the yolk was absorbefacient, the embryonic mouth opened, and the larvae could eat immediately after hatching.

The larvae were 3.63 ± 0.1 mm in length, fed on Brachionus plicatilis with a density of 5 inds/ml and Nannochloropsis oculata with a density of 10⁶ inds/ml for the first 5 days. After that, the larvae were fed on Nauplii of Artemia with a density of 5 inds/ml and after one month the fish were fed on fresh shrimp meat.

The 30 days old fishes were 12.84 ± 0.60 cm in length, 4.28 ± 0.18 cm in height and 0.0376 ± 0.0025 g in weight. The fishes were in bright orange color with two white stripes: one was at the middle of the back and the other was at the gill cover.

The 60 days old fishes were 15.96 ± 0.66 cm in length, 5.50 ± 0.61 cm in height and 0.0842 ± 0.0191 g in weight. The fishes developed well with three white stripe-orange body as an adult nemo.