Effect of lincomycin as a growth promoter for broiler chicks.

1. The effects of adding lincomycin to either the food (2.2 mg/kg) or drinking water (equivalent or 0.5 equivalent amount) of male broiler chicks were examined. 2. There were four treatments: control (no lincomycin), diet containing 2.2 mg lincomycin/kg, control diet plus drinking water containing lincomycin at concentrations calculated to provide an intake equivalent to treatment 2, and treatment 14 with lincomycin concentration reduced by half. 3. There was no significant effect of any treatment upon mortality, efficiency of food utilisation at 42 d of age, final body weights or monetary indices. 4. Analyses of breast, thigh and liver tissues, using a method with a sensitivity of 1.0 mg/kg, failed to reveal any evidence of lincomycin residues. 5. It is concluded that the use of lincomycin at 2.2 mg/kg may not be effective in improving either the biological or economic performance of the broiler chicken.