Can facial expressions and infrared thermography be used to measure positive emotions in goats

Nizar J. Hussein, Assel A.I. Al-Nakshabendy

Abstract: No study yet is undertaken to measure positive emotions in goats by stroking their body. Therefore, the present study was aimed to investigate the effect of stroking goats’ body as high valence and low arousal emotional state on facial grimace scale, ear postures and surface temperatures. The study lasted 10 months from September 2021 to May 2022. Thirty-two healthy goats were used in this study. Goats were stroked in three areas including forehead, neck and withers. The process was divided into three stages, which were pre-stroking, stroking, and post-stroking with five minutes for each stage. Results indicated that there were significant differences (P < 0.01) between all face units measured, except the ear position. In addition, significant differences (P < 0.05) were found in the positions of forward, backward and asymmetrical ears, while time spent with plane ears was not significant. Similarly, there were significantly (P < 0.05) higher ear position changes during both stroking and post-stroking periods, compared to pre-stroking stage. The stroking procedure had a significant effect (P < 0.05) only on eye and nasal temperatures during stroking and post-stroking stages compared to the stage before stroking, whereas no significant effect was found on the ear temperature. It was concluded that facial expressions and peripheral temperatures are vital indicators in measuring positive emotional valence in goats.

Keywords: ear position; Facial expressions; peripheral temperatures; positive emotions

Date published: 2023-08-21