INVESTIGATIONS ON THE APPLICATION OF AN E XTERNAL FETAL ELECTROCARDIOGRAM IN BOVINE OBSTETRICAL DIAGNOSIS FOR EVALUATION OF FETAL VITALITY

In 33 pregnant cows a fetal electrocardiogram (EGG) using an external lead was recorded during second stage of labor. A curve of the fetal h eart rate pattern was drawn which served to determine the following pa rameters. basal heart rate, and amplitude as well as frequency of hear t rate oscillation. These parameters were compared with APGAR scoring, colostrum intake, blood gas analysis as to their value for evaluation of vitality. There was a statistically positive correlation bet-vc ee n basal heart rate during birth and base deficit after birth, Basal he art rate was negatively correlated with plasma pH measured after fetal expulsion. Amplitude of heart rate oscillation was positively correla ted with pH in plasma and concentration of standard bicarbonate, and w as positively correlated with carbon dioxide pressure and base deficit . Calves with acidosis at birth or decreased colostrum intake had stat istically significantly higher amplitudes of oscillation than healthy control calves, Basal heart rate of the fetus when used as the only pa rameter might not be suitable in order to exactly evaluate fetal vital ity. In contrast, amplitude of heart rate oscillation more reliably in dicated a disturbance of fetal condition. Under practical conditions, the described procedure of measuring fetal ECG is suitable in order to detect a viable fetus.