Differential vocal responses to physical and mental stressors in domestic pigs (Sus scrofa)

摘要: Abstract Vocalisation can indicate an animal's emotional and/or physiological state. Thus, the detailed analysis of acoustic signals might provide a useful non-invasive method assessing welfare status animals. Focussing on vocal expressions distress, present study examined responses 10-week-old domestic pigs during classical conditioning paradigm, where neutral light stimulus (conditioned stimulus) was repeatedly followed by short electric shock (unconditioned stimulus). In contrast to physical distress elicited unconditioned stimulus, anticipation this aversive event constitutes fear, i.e., mental distress. Accordingly, three stages characterised distinct stressor qualities were defined: (1) non-anticipated stimulus; (2) anticipated (3) stimulus. Vocal comprised both high-frequency elements and low-frequency elements. High-frequency analysed using linear prediction coding (LPC) describe frequency structure. Calls compared MANOVA subsequently tested for their classifiability regarding stage non-parametric discriminant function analysis. The calls differed significantly between ( p