Selenium-enriched Nannochloropsis oceanica for aquaculture feed

Summary

The global demand for aquaculture is increasing and with aquafeed intensification there has been a demand for more sustainable feed ingredients. Wild fisheries are overfished and plant-based ingredients are the preferred sustainable alternatives to conventional fishmeal and fish oil from wild fisheries. There has been a focus on adding feed supplements such as vitamins and minerals for improving feed digestibility, increasing fish growth, and fish survival rates.

This thesis aimed at investigating the accumulation and speciation of Se in the marine microalgae N. oceanica, and its applicability as an organic dietary Se supplement in aquafeed at both laboratory and pilot-scale. Strategies were explored to improve Se accumulation and uptake efficiency. Finally, the Se-enriched N. oceanica was fed to gilthead seabream (Sparus aurata) and its bioavailability assessed. This thesis also discussed the current status and the future use of Se-enriched microalgae in aquaculture.