Culture of freshwater zooplankton Daphnia magna fed with different feed combination

Abstract

The study was focused on the culture of freshwater zooplankton Daphnia magna under different
feed trials. D. magna was collected from a pond and isolated based on its distinct morphological
characteristics. They were cultured in 12 glass jars containing 700 mL of tap water with different feeding
regimes: control (tap water only), green water (25 ml/L) (Tg), yeast (50 g/L) + green water (25 ml/L) (Tyg)
and yeast (16.6 g/L) + powdered green pea (16.6 g/L) + brown flour (16.6 g/L) (Tygb). Each of the control
and feed trials was set up in three replicates. Feeding and population count took place every third day over an
experimental duration of 21 days. The highest population density of D. magna was found in Tyg on day 15,
which was 207.1 individuals/L and the lowest was found in control, which was 23.80 individuals/L. Results
showed relatively better growth performance of D. magna in mixed feed trials compared to single or ‘no
feed’ trial. Among three feed trials, Tyg incurred the lowest cost compared to others and the cost to
production ratio was 7.8. The culture technique that have been standardized in the present study could be
applied to fish hatcheries and nurseries in Bangladesh.