The objective of this work was to evaluate the effects of dietary crude fiber contents on productive performance, carcass composition and physiological parameters of pacu juveniles. The experiment was carried out during 84 days, 360 pacu juveniles were used with mean weight 23.97±0.59 g, stocked in 30 tanks with 180 L of water, in a completely randomized design, with six treatments (5, 7, 9, 11, 13 and 15% crude fiber) and five replicates. Diets with high fiber contents (11, 13 and 15%) resulted in worse rates of weight gain, feed conversion, and specific growth, besides lower protein efficiency ratio and feed consumption. Carcass composition changed by increasing the contents of dietary fiber. Body contents of protein and ash increased along with the fiber levels. The metabolism changed with the use of increasing levels of fiber, which resulted in a slight elevation of serum cholesterol. Crude fiber content up to 9% had no negative effects on metabolism, but levels above 11% reduced fish growth.
Piaractus mesopotamicus; feeding; metabolism; nutrition
