Growth Performance and Profitability of Genetically Improved and Commercial Local Rohu (Labeo rohita) in Bangladesh

Abstract

Rohu (Labeo rohita) is a major aquaculture species in Bangladesh, but poor broodstock management has compromised seed quality and growth performance. To address this, WorldFish launched a genetic improvement program in 2012, yet the on-farm performance of the widely available third generation (G3) rohu remains poorly studied. This study aimed to evaluate and compare the growth and profitability of G3 rohu and commercial local rohu under typical smallholder pond polyculture systems in Bangladesh. A total of 120 ponds across two locations were randomly assigned to Selected (30 per location, G3 rohu) or Control (30 per location, local rohu), with rohu stocked at an average of 2470 ha−1 in typical smallholder polyculture systems alongside 5287 ha−1 of other cocultured species. The study was conducted over a full production cycle from July 2023 to March 2024, and differences in performance were assessed using multivariate regression and ANOVA models. Water quality remained within acceptable ranges for aquaculture, despite fluctuations. The Selected rohu demonstrated significantly higher (p ≤ 0.05) harvest weight, weight gain, survival rate, and specific growth rate (SGR), growing 32.6% faster than Control rohu. Productivity of cocultured species did not differ significantly (p ≥ 0.05) between ponds with Selected or Control rohu. Furthermore, G3 rohu yielded significantly higher returns per ha than local rohu, with total productivity, gross revenue, gross margin, net margin, and benefit–cost ratios (BCRs) all significantly higher (p ≤ 0.05) in ponds with Selected rohu. Regression analysis identified pond size, commercial feed use, inorganic fertilization, and stocking density as positive drivers of rohu productivity, whereas pond age had negative effects. Findings are based on data from two districts in southern Bangladesh and may vary elsewhere depending on local farming intensity and management practices. These results suggest that wider dissemination of genetically improved fingerlings, coupled with improved pond management, could enhance smallholder productivity and profitability in Bangladesh.