Feed the Future Innovation Lab for Collaborative Research on Aquaculture & Fisheries

The effects of selective harvesting (SH) ad claw ablation (CA) of blue-clawed (BC) prawns on an all-male freshwater prawn-finfish polyculture system were compared with control (Co) in quadruplicate. Ponds were stocked with all-male freshwater prawn Macrobrachium rosenbergii, silver carp Hypophthalmichthys molitrix, catla Catla catla and mola Amblypharyngodon mola at 12,000, 2,000, 500, and 20,000 ha^-1 respectively. Prawns were fed with pelleted feed. Ponds were fertilized regularly with urea, triple super phosphate and cow-dung. SH of BC prawns in treatment SH and CA in treatment CA started on the 60^th day during a 137-day culture and continued at 15-day intervals until the final harvest. Water quality parameters and plankton abundance did not vary significantly (P > 0.05) among the treatments. Treatment SH resulted in a higher (P < 0.05) net production of freshwater prawn (437 kg ha^-1), with better survival and mean weight, followed by CA (354 kg ha^-1) and Co (322 kg ha^-1). The combined net production of prawn plus finfish was also higher in SH (1244 kg ha^-1) as compared with CA (1161 kg ha^-1) and Co (1137 kg ha^-1), although the finfish production did not differ significantly. The periodic SH of BC prawns showed a better economic return with a BCR of 1.71.

NOP 10-A09 (English)