The biofloc technology (BFT) is an intensive and sustainable production system, in which microorganisms can contribute to the maintenance of water quality and serve as a complementary food source for reared animals. The aim of this study was to evaluate three production strategies and whether the biofloc system enables the dietary reduction of crude protein (CP) levels for pacu (Piaractus mesopotamicus). For this purpose, pacu juveniles were reared in three treatments: clear water with 27% CP (CW-27), biofloc with 27% CP (BFT-27), and biofloc with 22% CP (BFT-22). Growth performance parameters were assessed, as well as the physicochemical parameters and planktonic community of the water, in addition to the proximate composition of carcasses. Complementarily, the stomach content of fish submitted to fasting in different feeding periods was evaluated. As for the growth performance, all variables evaluated were higher in BFT-27 and BFT-22 compared to CW-27, with an exception of the specific growth rate. No significant differences were found between the diets offered in the BFT systems. Several microorganisms were found in the BFT system, which might be directly related to the higher growth performance of fish in comparison to CW. Even though pacu is not considered a species with filtering habits, its consumption of bioflocs was evident through the evaluation of the stomach content of fish during 48 h. This study demonstrated the technical viability of cultivating pacu in BFT systems, with a possible reduction of dietary protein from 27 to 22% CP, without affecting the growth performance of animals.

生物絮团技术 (BFT) 是一种集约化和可持续的生产系统，其中微生物有助于维持水质并作为饲养动物的补充食物来源。本研究的目的是评估三种生产策略，以及生物絮团系统是否能够降低日粮中 pacu ( Piaractus mesopotamicus ) 的粗蛋白 (CP) 水平。）。为此，在三种处理中饲养 pacu 幼鱼：含 27% CP (CW-27) 的清水、含 27% CP (BFT-27) 的生物絮团和含 22% CP (BFT-22) 的生物絮团。除了屠体的近似组成外，还评估了生长性能参数，以及水的理化参数和浮游生物群落。此外，还评估了不同喂食时期禁食的鱼的胃内容物。至于生长性能，BFT-27 和 BFT-22 中评估的所有变量都高于 CW-27，但特定增长率除外。在 BFT 系统中提供的饮食之间没有发现显着差异。在 BFT 系统中发现了几种微生物，与 CW 相比，这可能与鱼的更高生长性能直接相关。尽管 pacu 不被认为是具有过滤习惯的物种，但通过评估 48 小时内鱼的胃内容物，它对生物絮团的消耗是显而易见的。该研究证明了在 BFT 系统中培养 pacu 的技术可行性，可能将膳食蛋白质从 27% CP 减少到 22%，而不影响动物的生长性能。