An intensive chemostat culture system for the production of rotifers for aquaculture

An automated intensive continuous culture system, based on the principles of a chemostat, for producing two strains of the rotifer Brachionus plicatilis (L and S-type) has been investigated. Using 1-m³ capacity fiberglass tanks, it was possible to achieve a mean production of 308.75 × 10⁶ individuals m^-3 day^-1 of S-type rotifers and 186.71 × 10⁶ individuals m^-3 day^-1 of L-type rotifers in the culture system. The rotifers were fed with a local microalgal isolate Nannochloropsis strain MFD-2 which was produced using algal chemostats. Bakers' yeast was used as a feed supplement. The results show that the rotifer productivity in the continuous culture system is considerably higher than in any of the conventional culture systems described to date for aquacultural purposes. Furthermore, ω3-fatty-acid composition of rotifers in the culture system shows that these rotifers contain adequate quantities of essential fatty acids required for marine fish larvae and no further nutritional enrichment is necessary.