Which condition is classified as an unsoundness in horses?

Founder, also known as laminitis, is classified as an unsoundness in horses due to its serious and often chronic nature. This condition affects the sensitive laminae of the hoof, leading to severe pain and lameness. Founder can result in structural changes within the hoof and can severely impact a horse's ability to perform. It is often considered a serious unsoundness because it may require extensive management and can limit the horse's future usability for riding or competition.

While splints, fetlock lameness, and scratches can all affect a horse's soundness, they are typically viewed as less severe or more manageable in comparison to founder. Splints are bony growths that are usually manageable and may not impact a horse's performance to the same extent. Fetlock lameness can stem from various causes, some of which may be recoverable. Scratches primarily involve skin issues that may be treatable without leading to long-term unsoundness. Understanding the differences in severity between these conditions helps in evaluating the overall soundness and health of a horse.