Production, Preservation and Utilization of Freshwater Zooplankton for Fingerling Production
Freshwater zooplankton comprising of Diaptomus, Cyclops, Daphnia, Limnocalanus and Cypridopsis were cultured in outdoor concrete tanks using three levels (100, 150 and 200 g) of inorganic fertilizer (NPK). Multiplication of the zooplankton, harvesting and preservation was carried out for 21 days. Fertilizer was reapplied every week while maintaining the same level of water. Multiplication response and quantity of zooplankton produced varied with different treatments. Peak production was observed to occur from the third to the fifth day of fertilizer application and thereafter declined until fertilizer was reapplied. Mean total zooplankton production from the three treatments were 9.109 ± 7.326 g, 9.00 ± 7.166 g and 10.425 ± 7.595 g from 100 g, 150 g and 200 g fertilizer treatments respectively and 0.955± O.179g from 0 fertilizer treatment. Paired sample T -test showed no significant difference (P >0.05) between treatments Tl vs T2 and T2 vs T3 . The control showed significant difference (P < 0.05) with all other treatments. The sun dried zooplankton was used to feed C. gariepinus fry for four weeks. The fry fed on the zooplankton performed well with survival rate of 70 - 80%.
Key Words: Zooplankton production, preservation, utilization