Coagulation profile in different stages of pregnancy and under consideration of placental expulsion in dairy cattle.

It was the aim of the present study to determine different parameters of blood coagulation in dairy cattle in the course of gestation (n = 19) and during 9 days post partum (n = 40). The coagulation profile comprised prothrombin time, partial thromboplastin time, thrombin time, fibrinogen concentration, and platelet count. Prothrombin time was shorter in the 2nd month of gestation (13.9 s) than in the 7th (15.2 s) month. A reduction of partial thromboplastin time towards the end of gestation by approximately 4 seconds was statistically insignificant (p greater than 0.05). A significant change of fibrinogen concentration was established over a period of 10 days ante partum. Immediately before parturition, fibrinogen level (484 mg/dl) increased compared to one (325 mg/dl) and two (343 mg/dl) days before calving. Cows whose calves were developed per vias naturales displayed pronounced differences of fibrinogen concentration. Animals with retained placenta showed significantly higher fibrinogen concentrations than cows with normal expulsion of the placenta on all days.