Electrocardiographic examination in calves: a preliminary study

This study aims to describe and evaluate normal electrocardiographic parameters in calves.Twenty healthy male Holstein calves were included and divided into two groups of 10 animals each. Calves aged between 25 and 30 days have been enrolled in the Group 1. Calves aged between 177 and 183 days have been included in Group 2. The electrocardiogram were recorded with minimal restraint and without any sedation. Standard bipolar (I, II, and III) and augmented unipolar limb (aVR, aVL, and aVF) leads were recorded using 50 mm / sec paper speed and 10 mm = 1 mV for at least 5 minutes. QRS complexes, T and P waves were evaluated for duration and amplitude. The duration of the PR, QT and ST intervals was also measured. The analysis of the electrocardiography traces showed that the morphology of the QRS complex was of type Qr, QS or rS in both groups. The duration and amplitude of P, T waves and QRS complex showed minimal variations between two groups. The duration of the QT and RR intervals was higher in the Group 1 than the Group 2, instead the heart rate was decreased.