Phylogenetic identification and assessment of the nutritional value of different diets for a copepod species isolated from Eastern Harbor coastal region

Abstract

Cyclops spp. is among the most common zooplankton in fish larval rearing tanks of the Marine Hatchery of the National Institute of Oceanography and Fisheries, Alexandria, Egypt. This study aims to investigate the molecular analysis of this species and to evaluate the effect of a feeding diet composed of soybean, yeast, and microalgae (Tetraselmis chuii) on their population density and nutritional value. Phylogenetic identification of this species was conducted using (12S) rRNA molecular marker technique. The analysis showed that the investigated sample could be identified as Cyclops abyssorum divergens. Different concentrations of soybean and yeast ranging between 0.1 and 0.5 mg.l−1, and different microalgal density population ranging between 1.0 and 5 × 106 cells.ml−1 were used to feed cyclops for six consecutive days. The results showed that the treatment fed with soybean (0.5 µg/ml) recorded the highest population density of Cyclops (was 27 individuals/ml). As for the nutritional value, C. abyssorum divergens fed on T. chuii recorded the highest protein, lipids, and total amino acid values. Moreover, the highest value of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and other polyunsaturated fatty acids (PUFA) were detected in the C. abyssorum divergens growth fed on T. chuii.

Keywords

• Zooplankton
• Cyclops
• Molecular analysis
• Enrichment
• Population density
• Nutritional value