Sea and rock salt regulates a horse’s body fluids and is a good source of minerals. I try and point out to all my customers how important it is to use loose sea or rock salt. However, sometimes I do forget, so I'm shouting it out here. Even when I think I have pointed it out in black and white, sometimes I'll pop my head in a stable and I see a dreaded salt block.
WARNING, Salt licks are not good for our horses even the natural blocks are a problem. Salt licks were originally made for cows. Where a cow has a rough tongue and will get enough salt out of them however, horses have smooth tongues and they can not. A horse's mineral and salt needs change with the weather and their workload, and deficiencies are linked to many diseases. Most equine diets don’t have the right mineral balance or enough salt and mineral and salt blocks aren’t enough because a horse can’t chew at them to get out the right amounts. When you see a horse chewing at a block, cribbing or wood biting chances are they aren’t getting enough salt or have a mineral deficiency.
Sodium and chloride are combined to make salt and there isn’t enough in horse feeds to meet a horse’s minimum requirements. A forage based diet should provide a maintenance level of sodium, unlike most feeds. Also, feed companies are more likely to use table salt, a terrible product that is stripped of its minerals and that goes for the white salt blocks as well. Sodium (Na) has a similar function as potassium but is more important for horses that work hard or sweat a lot. A performance horse needs to self-maintain their Sodium levels with loose sea or rock salt and is essential to the health of this type of horse. If you were wondering what Chloride is used for, it is a key ingredient of bile and is used to produce hydrochloric acid for digestion.
A day after I had this conversation with one of my clients who owns a performance horse she sent me this photo.