Supplementing broiler diets with vitamin and mineral premixes are of concern. This concern is warranted due to the relative quantities needed and due to the adverse effects on the broilers that occur when inadequate dietary levels are fed. The objective of this experiment was to evaluate the effect of withdrawing vitamin and or mineral premixes from the grower and finisher diets of broilers. This experiment was arranged as a 2x4 factorial design. The factors being; a) supplement (ctrl) or non-supplementing one or both premixes in the diets and, b) two withdrawal times, 28 to 49 and 35 to 49d. Birds from each of the eight treatment combinations were assigned to four replicate pens of 30 birds each. Withdrawing of one or both premixes between 28 to 35 days of age had no significant (P>0.05) effects on body weight gain (BWG), feed efficiency (FE), and feed intake (FI). At the second withdrawing period, FI for birds fed diet with no vitamin supplement was statistically lower (P<0.05) than other treatment groups. Likewise, BWG for group without vitamin supplement and those, which lacked both premixes, were lower (P< 0.05) than other groups. Birds fed diet lacking mineral supplement had the worst FE, but this difference was only statistically significant (P<0.05) with the group fed lacking both vitamin and mineral supplement. Other criteria such as carcass characteristics, mortality and incidence of leg disorders were not statistically affected by treatments in the entire of this experiment (P>0.05). Our finding indicates that withdrawing premixes between the ages of 28 to 35 has little or no carry over effect on broiler performance. Key Words: Broiler, Mineral, Vitamin
