The purpose of this study was to evaluate the effects of ketoprofen (KTP), flunixin meglumine (FLM), and meloxicam (MLX) administration on acute-phase proteins after dehorning in Holstein heifers. A total of 21 Holstein heifers were enrolled into three groups of equal size (n=7) and administered ketoprofen, flunixin meglumine, or meloxicam, at doses of 2.2 mg/kg, 1.1 mg/kg, and 1 mg/kg body weight, respectively. Serum amyloid A, haptoglobin, and ceruloplasmin levels were determined before the administration of the three drugs (0 hrs) and at 6, 12, 24, 48, and 96 hours post-administration. The mean values (±SD) obtained revealed no significant alteration in APP levels at 0 hrs in any of the three groups. Time-dependent alterations, however, were significant in all groups. Group-time interactions were significant (P < 0.001) for ceruloplasmin concentrations, whereas results for serum amyloid A and haptoglobin levels were deemed non-significant. Inter-group interaction revealed no significant findings regarding serum amyloid A and ceruloplasmin levels, but haptoglobin levels showed a significant difference between the KTP and FLM groups at 48 hrs. It may therefore be reasonably suggested that KTP, FLM, and MLX could all be administered to effect slight changes in acute phase proteins.