Answer:
There are many things that can set in motion the process of laminitis. Any shock to the horse's system can result in founder. Some mares will founder after giving birth. An overly hot horse allowed to drink too much cold water can also be a cause. The more common causes are overeating on too rich food. Spring grass is much too rich for some horses. Other times too much grain or sweet feed. Any person that knows about horses has heard stories of unlocked feed rooms that are a magnet to hungry horses. Prevention is always the best way to go. Keep feed locked away, limit your horse on green lush pastures, cool your horse down before allowing him too much water. Some horses are more prone to this condition, ponies are usually the most vulnerable, so use good sense and you can reduce the risk of founder.