A simple method for measuring heart-rate in Guinea pigs during a standard handling procedure
Department for Animal Physiology, University of Bayreuth, Bayreuth, Germany
In the course of a longitudinal study on social stress in female Guinea pigs  we developed a simple and noninvasive method to estimate the heart rate during a standard laboratory handling procedure. The method had to meet the following requirements:
The investigated animals were familiar with a daily standard procedure which included weighing in a plastic basin since their first day of life. In order to avoid disturbing the animals we used this procedure as base for our heart rate measurement: The head of an electronic stethoscope (Bosch, Germany) was built in the weighing basin in a way, that it was directly under the chest of the Guinea pig (figs. 1 and 2). By using an underneath accessible adjusting device the stethoscopeís head could always be adjusted in an optimal position without touching the respective animal with the hands. The electronically amplified heart rate sounds and the animalís identification were recorded with a commercial two-speed dictation machine (Sanyo, Japan).
A measuring period of 30s proved to be sufficient for reliable results. The evaluation of the heart rate (beats per minute) was done with the help of the program The Observer (Noldus, The Netherlands). The heart beat sounds were played with half speed while a trained person had to press a key synchronously with the beats until the program ended the recording after 60 s.
Poster presented at Measuring Behavior '98, 2nd International Conference on Methods and Techniques in Behavioral Research, 18-21 August 1998, Groningen, The Netherlands
© 1998 Noldus Information Technology b.v.