Integrated multitrophic aquaculture applied to shrimp rearing in a biofloc system

This study aimed to evaluate the performance of an integrated multitrophic aquaculture (IMTA) system applied to shrimp rearing in biofloc technology (BFT). The IMTA system consisted of shrimp (Litopenaeus vannamei) in a rearing tank (800 L), a tilapia (Oreochromis niloticus) rearing tank (90 L), and a hydroponic bench with 0.33 m(2) of planting space for Sarcocornia ambigua culture. A submerged pump constantly pumped water from the shrimp tank to the tilapia tank. Then, by gravity, water flowed through the sarcocornia hydroponic bench and returned to the shrimp tank. The hydroponic bench had enough capacity for 32 plants. Shrimp, tilapia and sarcocornia stock densities were 312 shrimp m(-3) (250 shrimps per 800 L tank), 445 tilapia m(-3) (40 tilapias per 90 L tank), and 97 sarcocornia plants m(-2) (32 plant per system), respectively. The same experimental units were used in the control system which only differed by the absence of sarcocornia. The initial weight was 4.09 +/- 0.025 g, 1.16 +/- 0.02 g and 1.17 +/- 0.175 g for shrimp, fish and sarcocornia, respectively. Shrimps were fed according to the feed table, and the fishes were fed with 1% of fish biomass, stimulating tilapia to use biofloc as a food source. Results show no difference between shrimp and tilapia performance in either treatment. Only IMTA total yield (4.83 +/- 0.19 kg m(-3)) was significantly higher than that in the control system (3.99 +/- 0.045 kg m(-3)). Nitrate was higher in the control system (12.28 +/- 1.27 mg L-1) compared to the IMTA system (9.38 +/- 1.09 mg L-1).These results demonstrate a yield increase of up to 21.5% by multitrophic integration of L. vannamei, O. niloticus and S. ambigua in a biofloc system.