| Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 104 === One of the more conspicuous groups of fish on tropical reefs is the anemone fish. Anemonefishes are the most popular attractions of aquarists, and they are important in the aquarium trade, very high demand in the market, surface bright color and diverse, interesting display and especially the unique symbiotic relationship with sea anemones. Therefore, may be more prone to over-exploitation. The present study describes the embryonic development and early ontogeny of Premnas biaculeatus. Also, to investigate the effects of synthetic carotenoids to the skin pigmentation and fish growth.
Anemonefish spawned at 27-28°C. Spawning time concentrated in the morning about10:00 to12:00. The number of eggs at a single spawning ranged from 300 to 800. The eggs were orange in color, elliptical in shape, 1.7 mm in length and 1 mm in diameter. Incubation period lasted for 7 days. Hatching time is within 1 hour after sunset. Newly hatched larvae were having an average total length of 3.42 mm. Body coloration started darkening from 3rd and 4th day after hatching. By the 15th day, the juvenile attained all coloration pattern of an adult fish. On 30th day, all fins were well developed, the whole body was covered with light brown colored chromatophores and the average total length was about 11-12 mm. The larvae were fed with the rotifer Brachionus rotundiformis, copepod nauplii, Artemia nauplii and artificial diet.
The second experiment focused on feed were added with different carotenoids (astaxanthin and canthaxanthin) and different level concentrations (0, AS100, AS200, AS400, CA50, CA100, CA200) were fed on anemone fish (0.27 ± 0.01 g initial weight) for its growth and surface color changes during 60 days. There were no significant differences (p>0.05) were found in growth, SGR, FCR and survival rate among fish from all dietary treatments. The higher growth values were observed in fish feed CA100 diet with 89.74% growth and FCR 0.20 whereas lower growth in fish fed with no carotenoids (control) with 47.80% and FCR 0.39. The final weight varied from 0.39 to 0.46 g. The SGR ranged from 0.64 to 1.02 and survival in all treatments was high ranging from 85% to 100%. There was a general darkening with decreasing in L*, a* and b* after feeding astaxanthin and canthaxanthin. After 60 days of the experiment, L*, a*, b*, C* and H* values in the skin of CA50 fish were significantly (P<0.05) highest, whereas CA100 treatment group showing significantly (P<0.05) lowest values.
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