Evaluation of the population growth and fatty acid composition of Copepoda, Oithona nana, fed on different diets

The marine Copepoda species Oithona nana, is considered as one of the most Copepoda species that successfully mass cultured in marine hatcheries. This study investigated the effects of four feed diets (soybean, yeast, rice bran, and corn starch) on the population growth, growth rate, population composition, fecundity, and fatty acid composition of Copepoda, O. nana. The experiment was continued for 15 days and the copepods were fed on four feed diets with concentration of 1 g/106 individual/day. The results found that O. nana fed on corn starch showed the highest significant population growth (9067 Individual/L) and population growth rate (0.735). For nutritional value, copepods fed on rice bran were detected to have the highest content of monounsaturated fatty acid (MUFA), polyunsaturated fatty acids (PUFA), the lowest saturated fatty acids/unsaturated fatty acids ratio (SFA/UFA ratio) and the lowest SFA. More importantly, the rice bran diet was the only diet that showed eicosapentaenoic acid (EPA; C20:5ω3). Moreover, copepods fed on rice bran showed the highest significant female fecundity (8.33 egg/female), copepodite and nauplii percentages (33.27 and 32.65%, respectively). Finally, regarding to the quantity, corn starch is the most suitable diet for mass culturing O. nana, while, regarding to the quality, rice bran enhances the nutritional value and fecundity of the Calanoida Copepoda O. nana.