Freya Wood answers:
The question of when to retire an older horse is a challenge. In some cases, it’s very clear, for example when a horse has to retire due to an injury or other medical condition that ends their ridden career, but in many cases there is a less clearly defined answer.
Arthritis is a common condition in older horses and often a reason for retirement. There are options to manage early arthritic changes, particularly in younger horses. But when a treatment’s efficacy in maintaining soundness begins to wane, it may be time to consider reducing the level of work or looking to retire the horse completely. Older horses often have multiple joints affected by arthritis, in which case these treatments begin to become less appropriate.
In many horses, retirement is more phased, with the workload being reduced slowly over time, but some horses in their later years still enjoy a hack every so often if sound enough to do so. Every horse is an individual and the point of retirement will vary accordingly. Listen to your horse, he will know best.