The normal electrocardiogram of the unanaesthetized competition "Spanish Pouler" pigeon (Columba livia gutturosa).

This investigation was carried out on 64 healthy adult competition pigeons (Spanish Poulers) to determine reference values of electrocardiographic parameters in standard lead II; a comparative study between males and females was also performed to find changes in the electrocardiographic patterns related to sex. P wave was positive and monophasic; PR segment depression was present in 64% of records; the QRS pattern obtained was in most cases of the rS type, followed by the QS configuration. ST slurring (absence of ST) was observed in 47% of records and the mean electrical axis was in all cases negative. Statistically significant differences related to sex were found for P-wave, R-wave and T-wave amplitudes, showing the males have greater amplitudes than females, associated with the increase of cardiac tissue mass. No sex-related differences were found in heart rate and mean electrical axis.