Electrocardiogram reference values for the buzzard in Spain.

Electrocardiographic reference values were established on apparently healthy buzzards (Buteo buteo) in Lugo (Spain) from March 1997 to June 1999. All birds were anesthetized with isofluorane and placed in dorsal recumbence. The standard and augmented unipolar limb leads electrocardiograms were recorded in 65 buzzards. The wave forms were analyzed in lead II at 50 mm/sec and at 1 cm = 1 mV to determine P, PR, QRS, T and QT durations and P, QRS and T amplitudes. The polarity of each wave form was tabulated in all leads. The mean electrical axis (MEA) for the frontal plane was calculated using leads II and III. The mean heart rate was 325.2 +/- 52.9 beats/min. In lead II, the P wave was positive, the dominant pattern of QRS complex was QS and the T wave was always positive. The average value of the MEA was -99.2 +/- 7.7 degrees. Establishment of normal electrocardiogram (EKG) values will facilitate a better understanding of EKG changes seen in many diseases of these birds.