Abundance and diversity of zooplanktons in freshwater prawn macrobrachium rosenbergii (de man) culture ponds

The present study was carried out on the seasonal abundance and diversity of zooplankton in two culture ponds, control and probiotic experiment pond of freshwater prawn M. rosenbergii. Plankton samples were collected by plankton net and were narcotised with 20% ethyl alcohol and were preserved in 5% neutral formalin. The zooplankton abundance was influenced by physico-chemical factors. During the study period the occurrence of 30 and 32 species in control and experiment pond respectively were recorded with 4 orders namely Copepoda, Rotifera, Cladocera, Ostracoda. Among al groups copepod was the dominant order. Monthwise total zooplankton population in the probiotic experiment culture pond is 2065 in the momth of may whereas it is 1758 in July month in control pond. In the present experiments, cladocerans were observed maximum numbers in experiment pond than in control pond. The findings of the present study will help to improve the management strategies and roles of probiotics in improving and maintaining water quality in larval rearing water of giant freshwater prawn, Macrobrachium rosenbergii..