This work evaluated levels of digestible lysine on performance and carcasscomposition of barrows with high genetic potential for meat deposition. It wasused 80 animals with initial body weight of 95.55 ± 1.04 kg, distributedin a completely randomized block design, with 5 diets (0.540; 0.642; 0.744;0.846 and 0.948% of digestible lysine), eight replicates and two animals perexperimental unit. The experimental diets and water were provided ad libitumthroughout the experimental period. Digestible lysine levels did not changedaily feed intake and carcass weight of the animals. Daily weight gain and feedconversion improved in a quadratic way up to the estimated levels of 0.803 and0.871% of digestible lysine, respectively. It was observed an increasing lineareffect of the treatments on daily lysine intake and amount of meat. Althoughdaily meat deposition had increased in a linear way, the LRP was the model thatbest adjusted to the data which remained on a plateau from 0.803% of digestiblelysine level. The levels of digestible lysine influenced the P2 backfatthickness of the animals which decreased in a linear way. The digestible lysinelevel of 0.803%, corresponding to an intake of 24.60 g/day of digestible lysineprovides the best results of weight gain and meat deposition whereas the levelof 0.817% corresponding to an intake of25.30 g/day of lysine provides the best result of feed conversion, and the digestiblelysine level of 0.948% corresponding to an intake of 29.09 g/day of digestiblelysine provides the best results of meat deposition and backfat thickness ofbarrows from 95 to 125 kg.
