Changes in the plasma cortisol and glucose concentrations in ovariectomized cows infused with either adrenocorticotropic hormone (ACTH) solution (0.5 mg/2 L isotonic 0.9% NaCl solution per cow, ACTH) or isotonic NaCl solution (0.9% NaCl) for the first 12 h (gray shaded area). Values represent the mean SD. Significant differences are denoted by † (P 0.05) and ‡ (P 0.01) compared with baseline concentrations within each group and by “a” (P 0.05) and “b” (P 0.01) compared with the control group at the same time point.