MudroÀ P., J. Rehage, H. P. Sallmann, M. Höltershinken, H. Scholz: Stress Response in Dairy Cows Related to Blood Glucose. Acta Vet. Brno 2005, 74: 37-42.The aim of this study was to investigate whether different pre-surgical blood glucose concentrations have any effect on the course of cortisol and metabolic responses to surgical stress in dairy cows. Eighteen Holstein-Friesian dairy cows, admitted for treatment of left abomasal displacement (omentopexy), were used in the study. Abdominal surgery (the stressor) was performed in the standing position 16 -24 h after admission and lasted approximately 60 min. Blood samples were drawn from the jugular vein prior to surgery, immediately after and then 2, 5, 24, and 72 h after surgery. In order to test the effect of the different blood glucose levels on stress responses the experimental animals were allocated to two groups: 1) six hypoglycaemic cows (glucose < 2.4 mmol/l); 2) twelve normoglycaemic cows. Surgery increased blood glucose in both groups (p < 0.001), however, the glucose rise was less distinct in the hypoglycaemic cows. The surgical stress resulted in a significant increase in plasma cortisol concentrations in both groups (p < 0.001), however there was no difference in cortisol responses between the groups. Similarly, surgery enhanced the blood concentrations of free fatty acids (FFA) and L (+)-lactate in both groups (p < 0.001). In contrast, β-hydroxybutyrate concentrations slightly declined after surgery. On the basis of this study there appears not to be any effect of different plasma glucose on the cortisol and metabolite responses in stressed dairy cows. Therefore, it can be concluded that mechanisms regulating peripheral cortisol concentrations, and thus the animal stress response, are more dependent on the intensity of the stressful stimulus than on the energetic status of animal.