Polyculture of crayfish (Procambarus acanthophorus) and Nile tilapia (Oreochromis niloticus) as a strategy for sustainable water use

Background The crayfish Procambarus acanthophorus has a high potential for cultivation; however, it is necessary to evaluate its performance in polyculture with tilapia as a strategy for sustainable production in the rural sector where re sources are limited. Goals Assess the effect of polyculture of the crayfish and tilapia by measuring survival and growth. Methods Three methods of cultivation with three replicates were evaluated: T1) crayfish monoculture, T2) polyculture crayfish/tilapia and T3) tilapia monoculture. Nine high-density polyethylene tanks (3 m diameter x 1.2 m deep) were used during the trial. The tilapia were fed commercial feed, 32/5% protein / lipids, while the crayfish were given commercial shrimp feed with 35/7% protein / lipids. The productive efficiency of mono- and biculture was determined based on survival feeding efficiency and growth performance. Results Contrary to what was expected, interspecific competition, space, food availability, and weight gain of crayfish were similar in all treatments, whereas survival was influenced by the treatment, particularly during polyculture, where it was observed that tilapia affected the survival of crayfish. Unlike crayfish, tilapia maintained similar growth and survival in all treatments. Conclusions The results indicate that polyculture of crayfish/tilapia in a recirculation system is possible and promotes the use of the water column. However, it is necessary to consider the antagonistic effect between species.