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Analysis of the Normal Electrocardiogram in Wild Rooks ( Corvus frugilegus )
Abstract:
To describe the normal electrocardiographic (ECG) patterns and values in unanesthetized rooks ( Corvus frugilegus ), standard bipolar (I, II, and III) and augmented unipolar limb (aVR, aVL, and aVF) lead ECGs were recorded from 10 clinically healthy wild rooks. Wave forms were analyzed in all leads at 50 mm/s and at 10 mm = 1 mV to determine PR, QRS, ST, and QT durations; the net QRS complex; and P and T amplitudes. The polarity of each waveform was tabulated in all leads. The mean electrical axis (MEA) for the frontal plane was counted by using leads II and III. The mean heart rate was 340 ± 18 beats/min. The P wave was mainly positive in the most leads. The dominant pattern of waveforms of the QRS complexes was QS in leads II, III, and aVF, whereas in leads aVR and aVL, the patterns were rS and R, respectively. The T wave was positive in leads II, III, aVF, and aVL and negative in lead aVR. The mean of the heart MEA was -93 ± 2.2. Interpretation of the ECG values and patterns in rooks may facilitate a better realization of ECG changes of abnormalities in this species.
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