Marine fishes such as the common clownfish, Amphiprion ocellaris, have been exhibited in aquariums for over 60 years. The industry has grown to more than 30 million marine organisms, such as fish and invertebrates, being imported into the United States annually to support the aquarium industry. Clownfish are an important component of the industry. Bottlenecks in commercial production, such as unpredictable hatch rates and juvenile deformities, reduce profitability of U.S. based production. One key factor affecting the success of clownfish aquaculture is the broodstock diet. This study aims to compare three different diets to determine their effects on spawn size, egg fatty acid profiles, and the health of hatched embryos. By optimizing broodstock diet, this project seeks to address commercial production challenges, increasing output and reducing deformities in aquacultured clownfish.
A. ocellaris pairs held in 20- or 30-gallon tanks in recirculating aquaculture systems at Roger Williams University will be fed three different diets (LRS® Fish Frenzy and PE® Mysis, fresh Quahog and Sea Scallop, and a custom gel diet composed of fresh clam, scallop, squid, and sardine, fish protein concentrate, gelatin, supplemental DHA, astaxanthin, taurine, and vitamin C). Each pair will be allowed to spawn three times per feed trial, with the third spawn from each pair collected for analysis. A subsample of eggs will be collected from each clutch at two timepoints, the day after spawning and the day before hatching, to be processed for fatty acid analysis. Remaining eggs will be hatched, and larvae will be raised on a standard larval reference diet to approximately 60 days post-settlement to determine the impact of parental diet of juvenile deformities. Hatch rates and larval mortality will also be recorded to help quantify the quality of a spawn.
It is anticipated that the different diets used in this study will result in different hatch rates, clutch sizes, larval survival rates, and differences in deformity prevalence and severity. This project also aims to identify the fatty acids most crucial to A. ocellaris broodstock. The data generated will contribute to advancing the profitability of A. ocellaris production.