Use of threshold serum and milk ketone concentrations to identify risk for ketosis and endometritis in high-yielding dairy cows

Objective—To use threshold concentrations of acetone and β-hydroxybutyrate in milk and serum, respectively; identify risk for ketosis and endometritis; and assess analyses of blood and milk samples as predictors of risk for ketosis in high-yielding dairy cows. Animals—90 multiparous Holstein cows. Procedure—At intervals before and after parturition, blood samples were obtained for determination of glucose, nonesterified fatty acids, leptin, insulin, insulin-like growth factor-1, and β-hydroxybutyrate concentrations. Samples of milk were obtained at similar intervals after parturition for determination of fat content and concentrations of acetone, protein, and lactose. Reproductive examination of each cow was performed weekly. Results—For each cow, threshold concentrations of acetone and β-hydroxybutyrate were calculated as 75th and 90th percentiles of maximum postpartum concentrations of acetone in milk (0.40 and 0.87 mmol/L) and β-hydroxybutyrate in serum (2.30 and 3.51 mmol/L). Significant decrease in m...