Which vitamin is primarily obtained through exposure to sunlight for horses?

The vitamin that is primarily obtained through exposure to sunlight for horses is vitamin D. When horses are exposed to sunlight, specifically UV rays, their skin synthesizes vitamin D, which is crucial for various bodily functions, including calcium absorption and bone health. Vitamin D helps ensure that horses maintain strong bones and overall skeletal integrity, as it regulates calcium and phosphorus levels in the bloodstream.

While horses can obtain other vitamins from their diet, such as vitamin A from leafy green forages and vitamin E from fresh grasses, vitamin D is unique in its reliance on sun exposure for synthesis. This dependency makes it an essential factor to consider in equine health management, particularly for horses that may have limited access to sunlight due to factors like living in stalls or during winter months. Thus, the connection between sunlight and vitamin D synthesis is key to understanding its significance in a horse's diet and health.