Horses are highly social animals that suffer when kept in isolation. When same-species companionship is not available, carefully introduced companion animals can partially meet equine social needs.
The social deprivation of solitary horse keeping is a welfare compromise that is sometimes presented as unavoidable. Where a second horse is genuinely not possible, inter-species companionship is a welfare improvement worth pursuing. However, the value of companion animals must not be used to justify failing to provide equine companionship where it is achievable. Goats and donkeys are the most commonly used and generally successful companions for horses — they provide social interaction and reduce the visible signs of isolation. The bond between a horse and companion animal can be strong and grief-inducing if disrupted; owners should consider this when managing animal deaths or sales. The gold standard remains equine-equine companionship where at all possible.