Uso de probiótico multiespécies na fase de recria de Colossoma macropomum em sistema de bioflocos e água clara

Abstract

This study evaluated the effects of different strategies for the inclusion of a multispecies probiotic—administered via feed (PR), water (PA), or both (PAR)—in tão production systems, recirculating aquaculture system (RAS) and biofloc technology (BFT), on the zootechnical performance, body composition, physiological-immunological responses, and survival of Colossoma macropomum over a 70-day period. The BFT system presented higher pH, turbidity, and nitrite concentrations, while total ammonia levels were lower; conversely, the RAS maintained more stable water quality parameters (p < 0.05). Greater weight gain, productivity, and biomass were observed in the RAS under the PAR treatment (p < 0.05). Muscle protein content did not differ between systems (p > 0.05). Higher ash and lipid levels were detected in the RAS, although lipid content was reduced in fish receiving the PR treatment (p < 0.05). Hemoglobin and hematocrit levels were significantly higher in fish reared in BFT, whereas lower lactate concentrations were observed in the PA treatment (p < 0.05). Fish from the BFT system exhibited elevated levels of reactive oxygen species (ROS), serum lysozyme activity, and serum lytic activity (p < 0.05). Following a challenge with Aeromonas hydrophila, fish reared in RAS showed higher overall survival, while 100% survival was recorded in the BFT system under the PAR treatment (p < 0.05). These findings demonstrate that the interaction between production system and probiotic administration strategy can significantly enhance performance, health status, and disease resistance in juvenile tambaqui.