Marine Harpacticoid Copepod Culture for the Production of Long Chain Highly Unsaturated Fatty Acids and Carotenoid Pigments

Abstract

Nitokra lacustris Shmankevich, an epibenthic, coastal harpacticoid copepod species, is shown to provide several advantages for use as a live feed in the aquaculture of marine fish. This study addresses culture methods, population growth rate prediction, fatty acid composition and carotenoid content of N. lacustris. The highly consistent growth rate and the high proportion of highly unsaturated fatty acids (HUFA) and astaxanthin indicate that this species also has potential as a fish oil replacement in the animal feeds industry.

Nitokra lacustris was chosen as the test organism because of its small size, short generation time, high reproductive rates, and potential to contain substantial concentrations of long-chain HUFA and ketocarotenoid pigments. The ability of harpacticoid copepods to synthesize HUFA and ketocartenoids may be related to the highly variable coastal habitats of theses species. HUFA and carotenoids are important in energy storage and protection from cell membrane degradation for many marine plants and animals.

Nitokra lacustris contains a high amount of the essential fatty acids DHA and EPA as well as the essential carotenoid pigment astaxanthin, when compared to other live feeds (rotifers and Artemia). N. lacustris is also able to convert HUFA and astaxanthin from a diet that is deficient in these nutrients. The ability of N. lacustris to bioconvert essential fatty acids and carotenoid pigments without the addition of fish oil represents a potential new source of HUFA and astaxanthin for the animal feeds industry as well as for human health supplements