The objective of this study was to determine whether silica grit is a necessary dietary additive for turkeys raised in intensive production farms, and whether it can be replaced by other supplements such as charcoal or hardwood ash. The conclusions were formulated based on performance results, blood hematological and biochemical indices, the slaughter quality of turkeys, as well as on the chemical and physicochemical properties of turkey meat. The experimental material comprised 360 male Big 6 heavy-type turkeys randomly divided into 4 treatments and raised on litter until 20 weeks of age. Birds of all treatments were fed identical complete pelleted basal diets. The experimental factors were various feed supplements in each group. The control treatment was fed a diet without supplements. The diets for experimental groups were supplemented with silica grit (SG), charcoal (CH) or hardwood ash (HA) in the amount of 0.3% of the administered feed mix. Dietary supplements were administered from the first day of life until the end of the rearing period. No significant changes in blood hematological and biochemical indices of turkeys were observed. Silica grit (SG) had an adverse effect on the performance results of turkeys, while the addition of both CH and HA had a highly beneficial impact. The best results were reported in respect of charcoal. The treatment fed a diet supplemented with CH was characterized by the lowest mortality rate of 4.4%, i.e. half that observed in the control group, body weight higher by 3.9% and rearing efficiency index higher by 9.7%.