Electrocardiographic parameters of red-eared slider (Trachemys scripta elegans) in two temperatures

Abstract

The objective of this research is to evaluate the electrocardiographic parameters of red-eared slider (Trachemys scripta elegans) in order to promote reference values for the species, and to compare the results of the examinations in two different temperatures (24º C in stage 1 and 16º C in stage 2). Thirty healthy adults animals were used (17 males and 13 females) with average weight of 1.467 ± 0.312 kg. The measurements obtained in Stage 1 were: heart rate of 37 ± 8 beats/min, variation of mean cardiac axis between 60° and 90° in most animals; P wave amplitude of 0.041 ± 0.022 mV and duration 70 ± 26 ms, duration of the PR interval of 356 ± 167 ms, QRS complex du ration of 124 ± 21 ms and amplitude of 0.357 ± 0.167 mV, QT interval of 1002 ± 170 ms; isoelectric ST segment, with a mean TP duration of 348 ± 205 ms, positive T waves deflection in 20 animals and negative in 10 animals, with an amplitude of 0.118 ± 0.085 mV. However, the results observed In Stage 2 were a reduction in the heart rate (19 ± 6 beats/min). It was not possible to observe P waves in most of the animals, however, in the subjects in which it was possible to observe such waves, the amplitude was similar to the one of Stage 1, but with longer duration (120 ± 32 ms). There was an increase in the (duration of) PR interval duration (524 ± 162 ms), in QRS complex (175 ± 30 ms) and QRS complex amplitude (0.332 ± 0.138 mV); there was also an increase in the QT (1832 ± 410 ms) and TP intervals (1385 ± 861 ms), in the ST segment remained isoelectric and in T wave amplitude as well (0.218 ± 0.173 mV). Positive polarity was observed in most animals (20 animals) but the T wave was not observed in 10 animals. There was no statistical difference between males and females in two stages.