Zoological Studies

Electrocardiographic Studies in Formosan Macaques (Macaca cyclopis)

Sao-Ling Liang, Shih-Chien Chin, and Lih-Seng Yeh (2005) The Formosan macaque (Macaca cyclopis) is a threatened species, endemic to Taiwan. Data on the cardiovascular physiology of other nonhuman primates have been reported including electrocardiography, echocardiography, and radiography, but little is known of this aspect of Formosan macaques. In total, 38 clinically normal Formosan macaques (20 females and 18 males) undergoing routine annual health examinations were given electrocardiographic examinations at Taipei City Zoo. The mean weight of the animals was 10 ± 4.3 (range, 4-22.6) kg. The mean age of the animals was 6.9 ± 4.1 (range, 2-16) years old. Baseline parameters (heart rate, P wave, PR interval, QRS complex, QT interval and ST segment) of the electrocardiography (ECG) of Formosan macaques were established in this study. Values of the ECG parameters were a mean heart rate of 126 ± 20 beats/min, a mean P wave duration of 42 ± 7.8 ms, a mean PR interval of 97 ± 12 ms, a mean QRS complex duration of 43 ± 6.7 ms, and a mean QT of 296 ± 41.4 ms. Like other nonhuman primates, the Formosan macaque exhibited a sinus rhythm. Significant differences in ECG parameters were not found between males and females, between juveniles (< 7 years old) and adults (≥ 7 years old), or between animals with lighter body weights (≤ 10 kg) and heavier body weights (> 10 kg).