Electrocardiography of rock partridges (Alectoris graeca) and chukar partridges (Alectoris chukar).

Standard limb, six lead (I, II, III, aVR, aVL, and aVF) electrocardiograms (ECGs) were recorded in 10 awake mature rock partridges (Alectoris graeca) and 10 chukar partridges (Alectoris chukar). Durations and amplitudes of P and T waves and QRS complexes, durations of P-Q and Q-T intervals, and mean heart rates were calculated from the lead II ECGs. All observable P and T waves were negative in aVR and aVL, whereas they were positive in all remaining leads. The most frequent forms of QRS complex were r-s (r-S) and q-r (q-R). A Q wave was observed in all aVR and aVL leads in both species. Chukar partridges had significantly higher amplitudes of P and T waves and QRS complexes than rock partridges. Mean heart rates were 310+/-15 beats/min and 317+/-19 beats/min for chukar partridges and rock partridges, respectively. Mean electrical axes, calculated from leads II and III, were -99+/-6.3 degrees and -95+/-1.7 degrees for chukar partridges and rock partridges, respectively. Clear ECGs were easily obtainable without anesthesia or sedation.