This experiment was conducted to determine the effects of different levels and sources of copper (Cu) supplementation on serum ceruloplasmin (Cp) concentration and hematological values in Iranian fat-tail lambs. Twenty Iranian Mehraban male lambs were housed in individual pens and randomly assigned to 4 different treatment groups in a 2×2 factorial experiment based on a completely randomized design. Treatment groups consisted of 1) 10 mg Cu/d in the form of CuSO4, 2) 20 mg Cu/d in the form of CuSO4, 3) 10 mg Cu/d in the form of Cu-Proteinate and 4) 20 mg Cu/d in the form of Cu-Proteinate. Whole blood samples were analyzed for hemoglobin (Hb), red blood cell count (RBC), mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), packed cell volume (PCV) and red cell distribution width (RDW). Serum samples were analyzed for Cp concentration. Statistical analysis showed no difference between animals at d 0. The source of copper (proteinate vs sulfate) had a significant effect on serum Cp concentration, with proteinate leading to higher Cp values than sulfate (P<0. 01). Sheep which received 20ppm of copper (regardless of the source) had higher PCV and Hb values (P<0.01). Treatment No.4 had the highest Cp, PCV and Hb values but did not differ significantly from treatment No.3. These results suggest that organic Cu supplements are a more suitable source of Cu for sheep.
