Hormonal measurements in late pregnancy and parturition in dairy cows—possible tools to monitor foetal well being

Three dairy heifers (A, B and C) were induced to parturition with two prostaglandin (PG) F2alpha injections on day 268 and 269 of pregnancy. Signs of approaching parturition were carefully observed. The following parameters were registered: degrees of calving difficulty, date and time of parturition, calf’s birth weight and calf’s sex. Body temperature was measured and blood samples were taken every 3 h 3 days before the first PGF2alpha injection until 3 days after parturition. The plasma concentrations of the PGF2alpha metabolite, progesterone, cortisol, oestrone sulphate and pregnancy associated glycoproteins (PAGs) were analysed. Heifers A, B and C delivered 48, 51 and 57 h after the first PGF2 injection, respectively. Heifer A delivered without any signs of calving difficulty, whereas, the parturition was considered to be slight and moderate difficulty occurred in the delivery of heifers B and C, respectively. The calf of heifer C, without any abnormal gross-evidences, was stillborn. All animals had retained foetal membranes. A slight increase of the PGF2 metabolite at the time of parturition was found only in heifer C, whereas the levels dramatically increased in all animals 15–24 h after parturition.