Lam My Lan, Duong Nhut Long and Jean-Claude Micha (2006). The effects of densities and feed types on the production of Macrobrachium rosenbergii (de Man) in the rotational rice - prawn system. Aquaculture Research, Volume 37, Issue 13, September, 2006, Pages 1297-1304.
Postlarvae (PL) of Macrobrachium rosenbergii (de Man 1879) were stocked at 1, 2, 3 and 4 PL m-2. Prawns were fed only pellets (P) and a combination of pellets and snail meat (PS) with three replications in 100 m2 plots in the rotational prawn - rice system. Water levels were 0.3 – 0.6 m in rice growing areas. The water temperatures at noon in the hot months were higher than the suitable range for prawns. The final mean weights of prawns in treatments 1, 2 and 3 PL m-2 were significantly higher than in treatment 4 PL m-2 (P < 0.05). The yields from different density treatments ranged from 194 ± 82 to 373 ± 32 kg ha-1 and increased significantly with the increases in prawn densities (P < 0.05). There was no significantly difference between the two types of feed on production parameters (P > 0.05). The total cost significantly increased at higher densities (P < 0.05), but it was not different between feed types (P > 0.05). Net profit and cost benefit ratio of treatment PS were significantly higher than in treatment P. In the present study, treatment 3 PL m-2 and treatment PS offered the optimal results.