[Electrocardiographic analysis of auricular electric systole in the sheep].

The different components of the electric auricular systole, as well as the possible relationship between them have been studied in 302 ECG from Merino Precoz sheep breed. A gradual increase in the P wave duration, RR interval, PQ interval and PQ segment accompanying the growth of the animal, has been obtained, whereas the P wave voltage decreases both gradually and significantly. An analysis of the P wave morphology shows a higher incidence of double waves over simple waves in 1 year old animals than in younger ones. A high correlation between the RR and PQ intervals as well as between the PQ interval and the PQ segment has been observed in all groups of the three leads studied.