Yield performance comparison between cultures of rice cum prawn (Macrobrachium rosenbergii) and rice cum fish (Cyprinus carpio, Oreochromis niloticus) in North-Eastern Bangladesh

Integrated and concurrent cultures in rice fields are a promising approach to sustainable farming as the demand for aquacultural and agricultural products continues to grow while land and water resources become increasingly scarce. Prawn farming mainly takes place in coastal regions in improved extensive to semi-intensive aquacultures but a trend to shift the industry to inland regions has been noticed. This inland study in Northern Bangladesh used different input regimes such as fertilizer and additional feed to compare the performance of prawn and fish in flooded paddy fields in regard to water quality measurements. Maximal net yields and body weight gain with minimized negative impact on water quality were found when initial body weights of prawn were optimized. Regarding yield factors in reference to the reduction of costs due to the avoidance of expensive fertilizer/feed and effort, prawn performed better than integrated fish cultures considering a higher market value of prawn with net yields of up to 97 ± 55 kg ha− 1 for unfed and 151 ± 61 kg ha− 1 for fed treatments. Rice yields of up to 4.7 ± 0.1 t ha− 1 for unfed and 4.4 ± 0.1 t ha− 1 were achieved for fed treatments. The findings suggest that for small scale farmers, prawn cum rice cultures are an economically profitable and comparatively easily manageable alternative to rice cum fish cultures.

► Long term experiment on rice cum prawn and rice cum fish cultures.
► Yield performance depends on initial weights and seasonal forcing.
► M. rosenbergii shows a high potential to be integrated into rice paddies.
► Rice cum prawn is economically profitable.
► Rice cum prawn is a comparatively easily manageable alternative to rice cum fish.