It’s well known that ZnO and antibiotics (Ab) are usually included in nursery diets as a therapeutic use to reduce the impact of weaning in young piglets. The objective of this study was to analyze the effect of removing ZnO and Ab associated with CP reduction in piglet’s diets in terms of mortality and days required to reach marketing BW (MBW, fixed at 105 kg). A total of 400 crossbreed piglets [Pietrain × (Landrace × Large White)] from 40 litters were used. During the nursery period, pigs were reared in 40 pens (10 piglets/pen) and assigned to 2 treatments taking into account the BW at weaning following a RCBD: medicated, M (2,480ppm Zn as ZnO, 120 ppm colistin sulfate, 300 ppm amoxicillin, 11.0 MJ/kg NE, 20.2% CP, 1.37% Lys) and unmedicated, Ø (10.6 MJ/kg NE, 16.5% CP, 1.20% Lys) diets until 35 d post-weaning. Thereafter, pigs were moved to a growing-finishing facility (maintaining the same littermates). Pigs were fed ad libitum the same commercial growing and finishing diets (10.0 MJ/kg NE, 16.0% CP, 0.95% Lys). Mortality rate (MR) was monitored from 0 to 14 d post-weaning. All animals were individually weighed at d 2 (CF; cross fostering), d 28 (weaning), d 42 (14 d post-weaning), d 63 (35 d post-weaning) and every 3 weeks until pigs were slaughtered. Data were adjusted using the Gompertz model: BW = A × exp{–exp[b – (c × t)]}; the predicted time to reach 7, 10, 20, 40, and 105 kg of BW were statistically analyzed by ANOVA by using the GLM procedure of SAS. No differences in time to reach BW of 7 (M = 34.2 d vs. Ø = 35.0 d; P = 0.22), 10 (M = 43.5 d vs. Ø = 44.3 d; P = 0.24), 20 (M = 65.4 d vs. Ø = 66.3 d; P = 0.31) and 40 kg (M = 95.4 d vs. Ø = 96.5 d; P = 0.28) were observed. In contrast, time to reach MBW was slightly higher in Ø pigs (179.3 d vs. 175.1 d; P = 0.01) and also had higher MR than the M (control) diet (11.7% vs. 4.5%; P = 0.02) during the 14 d post-weaning. Results suggest that removing ZnO and Ab (also reducing CP and Lys) in early diets, seems not to have a huge impact in the time to reach MBW but causes higher MR in the first 14 d post-weaning.