Water-soluble carbohydrates (WSC), can be partly removed from hay (and beet pulp) by soaking and rinsing.
Approximately 50% of the WSC drain out in one hour’s time.
Soaking for longer is not more effective. However, rinsing in larger volumes of fresh water does remove more WSC.
Warm water removes sugars twice as fast as cold water.
Unfortunately, soaking also removes important minerals and vitamins from the hay.
Soaking for 15 to 30 minutes results in the best balance between WSC reduction and mineral and vitamin retention.
Hay soaked for more than 12 hours potentially puts horses at risk of phosphorus deficiency.
Ethanol soluble carbohydrates (ESC) wash out more easily than fructans.
Starch is not water soluble and therefore remains in soaked hay.
Soaked hay will stay in the stomach only for a very short time, allowing bacteria to reach the small intestine and cause abdominal pain or colic.
Do not soak more hay than the horse can eat in one day. Wet hay turns mouldy quickly.
Keep wet hay clean. For instance, soak in a wheelbarrow, drain the residual water and let the horse eat out of the wheelbarrow.
Needless to say, do not allow the horse to drink the residual water.
Soaking hay should be an emergency solution when low NSC hay is temporarily unavailable.
Silage and haylage should not be soaked. A second fermentation could set in, leading to an increase of undesirable bacteria. Given the low level of WSC soaking is not necessary.
