EFFECTS OF COMMERCIAL ENRICHMENT DIETS ON THE NUTRITIONAL-VALUE OF THE ROTIFER (BRACHIONUS-PLICATILIS)

The rotifer, Brachionus plicatilis, pre-fed on baker's yeast, was enri ched for 6 h with three commercial products from Artemia Systems S.A., namely Protein Selco (microcapsules), Dry Selco (microparticles) and Super Selco (an emulsion containing high levels of n-3 HUFA). The bioc hemical composition (protein, carbohydrate, total lipid, lipid classes and fatty acids) and dry weight of the rotifers before and after the enrichment experiments were studied. Two of the enrichers, Dry Selco a nd Super Selco, are rich in lipid but poor in protein and carbohydrate . Protein Selco contains lipid as well as protein and carbohydrate. Th e biochemical composition and the dry weight of the rotifers were chan ged after 6 h of enrichment. The percentage of protein and lipid incre ased with all of the three enrichers and the percentage of carbohydrat e decreased slightly. Rotifer dry weight increased in rotifers enriche d on Protein Selco. Phospholipids, sterol esters + waxes, triacylglyce rols and free fatty acids increased after the enrichment with the thre e enrichers while sterols slightly decreased when the rotifers were fe d on Protein Selco. The fatty acid content of the rotifers increased a fter the enrichment with all of the enrichers and this increase was pa rticularly apparent in the case of n-3 HUFAs (20:5n-3 and 22:6n-3).