Plasma and liver metabolites and glucose kinetics as affected by prolonged ketonemia-glucosuria and fasting in steers.

For 28 days, four steers received 1,3-butanediol, which causes ketonemia, and phlorizin, which causes glucosuria. Steers also were fasted for 9 days. Effects of treatments on concentrations of metabolites in blood and liver and on kinetics of glucose metabolism were determined. Treatments were: control, control with dietary butanediol plus injected phlorizin, and fasting. Fasting caused hypoinsulinemia and decreased liver glycogen by 60%. Butanediol plus phlorizin and fasting caused 18 and 19% decreases of plasma glucose and 2.5- and 6-fold increases of free fatty acid concentrations in blood plasma. Glucose irreversible loss averaged 371, 541, and 182 g/day during control, butanediol plus phlorizin treatment, and fasting. Butanediol plus phlorizin increased liver ketone body concentrations, caused glucosuria, ketonuria, and ketonemia, but did not affect insulin, glucagon, or growth hormone concentrations in plasma or triglyceride and glycogen contents in liver. Steers given butanediol plus phlorizin did not show all the usual signs of lactation ketosis, but the treatment still offers promise for studying causes and effects of ketosis.