Waste-grown heterotrophic microorganisms improve the production of Apocyclops dengizicus

Abstract Copepods are one of the essential live feeds in aquaculture and are commonly raised on algal diets. However, sustainable copepod productions in captivity are still unachievable due to lack of cost-effective feed and reliable culture protocols. Hence, this study investigated the effects of palm oil mill effluent (POME) grown marine microheterotrophs (bacteria, yeasts and protists) on the survival, population growth and F2 nauplii production of brackish water copepod, Apocyclops dengizicus, at laboratory scale. For each feeding experiment, an initial stocking density of fifty copepod nauplii (stage I) with triplicates of each treatment was cultured for the duration of twelve days. Copepods fed with POME-grown marine yeast, Meyerozyma guilliermondii (POME-MG), had significantly (p   .05). POME-MG and POME had comparable amounts of protein of 41.8% and 38.8% (on a dry weight basis), polyunsaturated fatty acids of 8.0% and 9.2% of total fatty acids and essential amino acids of 47.2% and 46.6% of total amino acids, respectively. However, the former diet had significantly higher amount of carbohydrate (24.8%) but lower content of lipids (11.0%) than the latter diet which contained 6.1% carbohydrate and 27.1% lipids. Our findings show that waste-based diets in particular POME-MG is suitable for mass culturing A. dengizicus because it enhances survival, population growth and nauplii production. Most importantly, such production method is scalable and economically viable as it requires a minimal production cost to achieve high copepod densities in the shortest time.