[The effect of subclinical and acute ante partum acidosis in cows on the course of pregnancy with regard to the steroid hormone profile].

Experiment 1: In a field experiment in 19 of 87 cows being in day 260-265 of pregnancy subclinical metabolic acidosis was found. The control group included 10 healthy cows in the same stage of pregnancy. Blood samples from cows of both groups were collected once daily until day 2 post partum for determination of oestrogens, progesterone and cortisol. Dystocia was found in four and retained placenta in three cows having acidosis. These cows had lower oestrogens and markedly higher cortisol and progesterone concentrations during parturition. Course of pregnancy and delivery in control cows an without any difficulties and hormonal profiles in these cows were typical. Experiment 2: On day 265 of pregnancy experimental acute acidosis was evoked in five cows and five other cows served as control. Sampling of blood was the same as in experiment 1. Acidosis caused on day 269 in two cows premature birth with retained placenta. Moreover concentrations of studied steroids were atypical. In three other cows with acidosis course of pregnancy and delivery was without any trouble. Only cortisol was increased while progesterone and oestrogen values were in agreement with concentrations of control cows. Data suggest that metabolic acidosis can cause dystocia, premature birth and retained placenta. Furthermore, acidosis clearly affects the profile of steroid hormones.