Suplementation of the microalgae Arthrospira platensis powder in the nursery phase of Pacific white shrimp (Penaeus vannamei, Boone 1931) in a biofloc system
摘要
This study evaluated the effect of adding dry biomass of the microalgae Arthrospira platensis (Spirulina) into the water on shrimp growth, water quality, and proximal composition of Penaeus vannamei post-larvae in a biofloc system. Four treatments were tested with three replicates each: a control treatment consisting of a biofloc system (BFT) without the addition of Arthrospira platensis; a biofloc system with the addition of 40 mg L−1 of A. platensis powder (Sp40); a biofloc system with 50 mg L−1 of A. platensis powder (Sp50); and a biofloc system with 60 mg L−1 of A. platensis powder (Sp60). The post-larvae shrimp, with an initial average weight of 0.02 ± 0.01 g, were stocked at a density of 2000 m−3 in tanks with a useful volume of 50 L. They were fed with commercial feed. The experiment lasted 35 days and evaluated performance parameters, water quality, and the proximate composition of shrimp and biofloc. Treatments with A. platensis showed improved biomass gain, better survival, and feed conversion rate, with a higher protein content in the shrimps when compared to the control. The water quality parameters were significantly influenced by A. platensis, with lower pH and higher nitrate and phosphate concentrations, particularly in Sp50 and Sp60 treatments. However, all water quality parameters remained within tolerance levels for shrimp growth. Thus, among the treatments tested, the treatment with the addition of 50 mg L−1 of A. platensis powder positively influenced shrimp survival, biomass gain and improved their proximate composition in the nursery phase of P. vannamei in the biofloc system.