Survival, proximate composition, and proteolytic activity of Artemia salina bioencapsulated with different algal monocultures
This study focused on testing Artemia sp. zooplankton saturation with freshwater microalgae biomass and then using this method to correct the nutritional composition of Artemia. Accordingly, the influence of three species of microalgal monocultures was analyzed (2 freshwater – Desmodesmus armatus (Chod.) Hegew. and Chlorella vulgaris Veijerinck; one halophilous – Dunaliella viridis Teodor.). The algal monocultures were applied once in a quantity of 2-3 × 106 cells × l-1 for each 200,000 Artemia individuals hatched. The control group Artemia did not receive algae. The enrichment process lasted 24 h, and control measurements were performed every 6 h. The survival of Artemia nauplii, their proteolytic activity, and the content of proteins, lipids, and carotenoids were analyzed. The choice of algae species for Artemia enrichment was guided by the size of the algal cells and their biochemical composition. Selected algae contained about 50% protein, 20% lipid, and 12 mg of carotenoids per g of dry weight. Using algae to saturate the Artemia nauplii permitted reducing their mortality during the 24 h enrichment regime. The introduction of C. vulgaris biomass halved this value. The use of algae also increased the proteolytic activity in Artemia nauplii and the content of proteins, lipids, and carotenoids in their biomass. The best results of the bioencapsulation of Artemia nauplii with algae was with the C. vulgaris biomass.