- The production of Macrobrachium rosenbergii monosex populations was examined under intensive growth conditions in cages. It was found that an all-male population yielded 473 g/m 2 within 150 days, whereas an all-female population and a mixed population produced 248 g/m 2 and 260 g/m 2 , respectively, during the same growout period. Since the performance of the mixed population in cages is comparable to that of a normal typical juvenile population in commercial earthen ponds, with an average production of 2500–3000 kg/ha, it appears possible to obtain a yield of 4700 kg/ha within 150 days from all-male populations grown under intensive monoculture conditions. A comparison of growth performance of each of the sexes when raised alone and when raised in mixed populations showed that whereas females are strongly affected by the presence of males, resulting in growth inhibition, males are hardly influenced by the presence of females. The findings of this study call for intensive efforts in research directed towards the controlled establishment of prawn monosex populations.