Within samples collected twice weekly, serum concentrations of glucose, insulin (beginning on d 14 of the experiment), and NEFA (preprandial samples only) were greater (P ≤ 0.05) in HIGH compared with HIGH- CR cows and tended to be greater in HIGH compared with MAN cows (P ≤ 0.10) but did not differ (P ≥ 0.52) between HIGHCR and MAN cows. Moreover, HIGH cows had reduced RQUICKI compared with MAN (P = 0.02) and HIGHCR cows (P = 0.05) whereas RQUICKI was similar between MAN and HIGHCR cows (P = 0.53). Within samples collected during the GTT, mean serum insulin concentrations and insulin:glucose ratio were greater (P < 0.01) in HIGH compared with HIGH- CR cows, tended (P ≤ 0.09) to be greater in HIGH com- pared with MAN cows, and were similar (P ≥ 0.16) between HIGHCR and MAN cows. Serum glucose con- centrations were greater (P < 0.01) for HIGH compared with MAN and HIGHCR cows 20 min relative to infu- sion. In conclusion, chromium propionate supplementa- tion prevented the increase in insulin resistance caused by excessive energy intake in nonlactating dairy cows.