An experiment using a double 4 × 4 Latin square design was conducted to study the effects of NaHCO₃, limestone, and bentonite at 2% levels on feed intake, rumen fermentation, and blood mineral concentrations of canulated lambs changed abruptly from brome hay to a 92% concentrate diet followed by a 7-day feeding period. Although slight benefits regarding feed intake and maintenance of rumen pH were obtained by adding NaHCO₃ to the high-concentrate diet, buffers generally did not prevent the acidosis-related changes in rumen lactic acid, VFA, or plasma mineral concentrations occurring after high-concentrate feeding.