Objective: Hyperketonemia remains a major metabolic issue of serious milk production and health concerns in early lactation cows. Oral supplementation of glucose precursors (GP) can be used to prevent hyperketonemia in dairy cows. The objective of this study was to compare the beneficial effects of orally supplementing a mixture of GP on metabolic health indicators and milk production status of primiparous and multiparous dairy cows.Methods: Twenty-eight Holstein cows were blocked by expected date of parturition, previous lactation yield, and parity. The cows were randomly allocated to one of the four treatment groups (n = 7 cows/group) based on their parity and GP supplementation: 1) primiparous cows fed basal diet only (PP-CON), 2) primiparous cows with oral supplementation of GP (PP-GP), 3) multiparous cows fed basal diet only (MP-CON), and 4) multiparous cows with oral supplementation of GP (MP-GP).Glucose precursor (Glycoline liquid) was orally drenched (300 mL/day) in GP cows from 7 days prepartum through 7 days postpartum. Other than GP supplementation, all cows were fed similar preand postpartum basal diets. Results:In both pre-and postpartum periods, serum glucose concentration was increased, whereas βhydroxybutyrate and free fatty acids were decreased in GP cows compared with the CON cows. Milk yield and milk components were statistically not different between GP and CON cows over the first 9 week of lactation. The yield of actual milk, energy-corrected milk, 63-days cumulative milk, colostrum yield, and calf birth weight remained higher in MP cows compared with PP cows. Conclusion:Oral drenching of GP around calving can be recommended to successfully improve the metabolic health and reduce the negative effects of hyperketonemia not only in multiparous but also in primiparous dairy cows.