Ultrasonic vocalizations in the common marmoset (Callithrix jacchus). A pilot study.

Abstract

The common marmoset (Callithrix jacchus) is commonly used in biomedical research. For monitoring of their welfare in captivity, an objective measuring tool would be important. The aim of this study was to see if ultrasonic vocalizations (USV) might be a useful objective parameter in the assessment of pain and distress in these small primates. During different neutral, positive and negative trials, the occurrence of USV were measured and investigated. It was found that the common marmoset indeed produces USV and that these seem to occur mostly in stressful situations. However, it also seems to be that USV do not occur solely, but that the audible vocalizations of marmosets in some cases extend into the ultrasonic range. Vocalizations, both audible and in the ultrasonic range, may be used as an objective non-invasive and non-intrusive measurement for welfare in common marmosets.