In the absence of stress, horses blink eight to nine times per minute. Eyelid twitches occur two times per minute, writes Nancy Loving, DVM. She shares key details from a study at the University of Guelph that monitored eye blinks and eyelid twitches as a non-invasive measure of stress in horses. Several stressors were used to test the validity of using blink rate as an appropriate stress measure.
. . . both full and half blinks decreased in the “stressful” conditions.”
Source: EquiManagement, February 6, 2023. Link.
INSIGHTS: Eye blinking monitoring would seem to be a teachable welfare monitoring skill veterinarians can share with supporting persons and horse owners during exams and procedures.