[Distribution of surface electric potentials in the horse heart]

Surface electric potentials of the heart of four horses were measured by use of unipolar leak with the so called central Wilson's clip; the measurements were performed on 95 precisely fixed places of the equine body. Potentials found out in this way were re-measured with bipolar leaks: the negative electrode was fixed in the place of the highest negative potentials, the positive electrode was gradually attached to places with the highest values of positive potentials. The largest potential differences when the negative electrode was placed in the region of the heart were obtained from the region of the withers, spinal and scapular regions, from forehead and nose. On the basis of these potential differences the most suitable places for uni-leak bipolar electrocardiography and radiotelemetric registration of EKG were selected. Bipolar leak -- apex of the heart -- withers -- appears most suitable; it provides the best potential and time reproducibility of EKG. The results have been processed statistically and arranged graphically.