90 clinically healthy cattle with a normal estrus cycle (German Black Pied) were investigated. Normal values for the physiological coagulation profile including prothrombin time, partial thromboplastin time, thrombin time, and fibrinogen concentration were determined. The following ranges of normal values (means +/- 2SD) were calculated: prothrombin time (PT) 20.1-30.1 seconds; partial thromboplastin time (PTT) 25.3-44.5 seconds; thrombin time (TT) 12.4-17.2 seconds, and fibrinogen concentration 125-697 mg/dl. During the day and day to day variations in the individual parameters of the coagulation profile were not observed.