Researchers recently determined that horses appear more bothered by social isolation than mild pain. | Photo: iStock

But what happens when the horse is removed from the herd? Separating a horse from its companions for veterinary care, hoof trimming, or training is likely more distressing for group living than for individually stabled horses. The distress might also be more severe when the procedure is painful or unpleasant.

In a recent study published in the Journal of Veterinary Behavior, Katherine Reid, MS (Biomed), BVSc, and associates at Massey University’s Equine Research Centre, in New Zealand, evaluated what happens when horses are isolated from conspecifics during routine equine management procedures.2 They looked at the separate and combined effects of social isolation and mild pain in six Standardbred horses which had lived together on pasture for two years as part of the university’s teaching herd and were regularly handled by veterinary staff and students.

To see how horses would respond behaviorally and physiologically to social isolation and mild pain, the researchers first placed each horse in a turnout next to a familiar herdmate, with visual, olfactory (scent), and tactile contact over a fence