Figure 4. Low responsiveness to environmental stimuli by “withdrawn” horses.

(a) Proportion of horses with high reactivity scores (i.e. ≥12; as 12 is the median score, thus including the 50% more reactive horses) for reactions to von Frey filaments applications, and (b) “C” scores (indifference, i.e. no change in activity) in the sudden human approach test. Data for (b) are given as boxplot diagrams showing medians (lines in the boxes), 25 and 75% quartiles (boxes) and minimum and maximum ranges (whiskers). Only half of the “withdrawn” horses had a high total reactivity score, whereas most of other horses (i.e. that never displayed the withdrawn posture) did. “Withdrawn” horses also displayed more often indifference to a sudden human approach than non- withdrawn off horses. Chi-square and Mann Whitney tests, ** p<0.01.