Defensive responses of Brandt's voles (Lasiopodomys brandtii) to chronic predatory stress.

Predator odors are non-intrusive natural stressors of high ethological relevance. The objective of this study was to investigate the processing of a chronic, life-threatening stimulus during repeated prolonged presentation to Brandt's voles. One hundred and twenty voles were tested by repeated presentation of cat feces in a defensive withdrawal apparatus.