Enhancing Growth Performance, Coloration, and Body Composition in Hatchery-Produced False Clownfish (Amphiprion ocellaris) Through Dietary Astaxanthin Supplementation Derived from Shrimp Shell Waste

Coloration is a critical factor determining the value and marketability of marine ornamental fish, particularly in the false clownfish (Amphiprion ocellaris). However, a significant challenge for current hatchery-produced false clownfish is their inferior coloration (pale, dark, less vivid) compared to wild-caught specimens. The present study assessed the dose-dependent impact of astaxanthin supplementation in the diet, sourced from shrimp shell waste, on growth performance, coloration, and body composition in hatchery-produced false clownfish. Six experimental groups, each containing 15 fish, received diets supplemented with astaxanthin at levels ranging from 0 (control) to 1000 mg/kg, with increments of 200mg/ kg, for 75 days, with three replicates per treatment. The findings revealed that astaxanthin supplementation notably improved growth parameters during the juvenile stage, including length-specific growth rate (SGR_L) (13.79–41.38%/day), weight-specific growth rate (SGR_W) (13.33–42.67%/day), and feed conversion ratio (FCR) (6.03–22.11%). Skin coloration, measured by the a^* value and total carotenoid content, was enhanced by 93.65–163.74% and 140.78–341.20%, respectively, compared to the control group. Increasing dietary astaxanthin levels positively affected body protein composition while reducing lipid content. Based on the obtained results, a supplementation level of 600mg/ kg feed appears sufficient to improve the quality of the hatchery-produced false clownfish. These findings demonstrate the effectiveness of astaxanthin derived from shrimp shell waste in enhancing growth performance, coloration, and body composition in the hatchery-produced false clownfish, which is crucial for improving the acceptance and value of hatchery-produced fish in ornamental fish markets.