Blood Glucose, Insulin and Inorganic Phosphorus in Healthy and Ketotic Dairy Cows after Intravenous Infusion of Glucose Solution

The aim of the present study was to determine the degree of blood glucose utilization by peripheral tissue on the basis of changes in blood concentrations of glucose, insulin and inorganic phosphorus in healthy (n = 10) and ketotic cows (n = 10) after intravenous infusion of glucose solution. Blood samples were taken in both groups of examined cows at the following time intervals: just before (time 0) and 30, 60, 120, 180 and 240 min after intravenous infusion of a total of 500ml of 50% of glucose solution. Glucose and insulin blood serum values in both groups of cows increased significantly within 30 and 60 min of the experiment (p < 0.05). Significantly lower values (p < 0.05) of insulin in blood serum of ketotic cows compared to the healthy ones were established within 30 and 60 min of the test. This indicated that the ability of beta cells of the endocrine pancreas to release insulin is reduced in cows suffering from ketosis. After intravenous infusion of glucose, it was established that values of inorganic phosphorus were decreased in blood in both groups of cows. Within 180 and 240 min of testing there was a significant decrease (p < 0.05) in the blood value of inorganic phosphorus in ketotic cows compared to the healthy ones. This is linked with the active entry of glucose into the glucolytic pathway of peripheral tissues. It can thus be concluded that there is a higher degree of blood glucose utilization by peripheral tissues in ketotic cows.