[Reactions of heifers in early pregnancy and their offspring delivered at term by cesarean section and in the first postpartum days in a cow-calf operation].

In 11 heifers originating from one mother cow herd and in their offspring delivered by cesarean section heart rate recordings were taken during their staying in the calving box and later on in group housing. Heart rate showed a rhythmicity in accordance with behavioural physiological reactions. The mean heart rate of a 24 hour period in an animal was different between and within the newborn and elder animals. The mean heart rate was increasing in the calves during the first days of their postnatal life and decreasing in the mother cows within some days after parturition. Blood samples taken repeatedly in 9 heifers via an indwelling catheter and in their offspring short after birth and at 24 and 48 hours by venipuncture as well were analysed for acid-base status, cortisol, noradrenaline, adrenaline, hemoglobin and lactate. Comparing the results with other investigations can be used for evaluating the strain of delivery by cesarean section for the young and the mother as well as revealing main influences on the reactions of the animals and their individual specificity.