Molecular characterization and culture optimization of marine copepod Oithona dissimilis (Landberg, 1940) from Nagore coastal waters, Southern India

This study focused on identifying the cyclopoid copepod Oithona dissimilis found in the Nagore coastal waters of Southern India. Based on both morphological and molecular approaches to identify this species. Morphological characters were confirmed by examining the arrangement of setae and spines on the exopod of swimming legs 1-4. Molecular studies were performed using the CO 1 gene, which proved an effective marker for species identification. After identifying the Oithona dissimilis, reared them under laboratory conditions to determine the effects of various environmental parameters on their survival, nauplii production, and population density. Tested different temperatures, light intensity, pH, salinity, and diets and found that the optimum conditions for rearing Oithona dissimilis under laboratory conditions were a salinity of 25 PSU, a temperature range of 24-28{degrees} C, pH of 8, light intensity of 500 lux, and a mixed algal diet at a concentration of 30,000 cells/ml. The present study confirms the importance of accurate taxonomic identification for the Oithona group at the species level. Additionally, our findings show that rearing cyclopoid copepods under laboratory conditions that mimic their natural range of environmental parameters is crucial for the thriving culture of these organisms, the aquaculture industry frequently utilizes this as a live feed. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=87 SRC="FIGDIR/small/580272v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@ecae13org.highwire.dtl.DTLVardef@987662org.highwire.dtl.DTLVardef@1844230org.highwire.dtl.DTLVardef@158e4d_HPS_FORMAT_FIGEXP M_FIG C_FIG