Walked into field today to find my 4 yr old welsh c eating sand (I am in UK) give her multi vit in the feed so unsure why she is doing this--advise please>>>>
Does she have a salt lick? If not that might help. Also, was she eating sand instead of feed or was there no food, in which case she may have been trying to forage and you might want to look at small hole haynet a to ensure she always has a better option than the sand.
It might be just as others have suggested horse may need a salt lick those lava ones are brilliant as are the large Rockies Chelated.
To see how much sand your horse is actually ingesting - get some poo and stick in a jar, put water in and shake vigorously (ensure lid is TIGHT) and leave for a while and you will see the sand all fall to the bottom.
Easy and simple trick
Sand colic usually is where they do ingest copious amounts so do becareful but the jam jar trick should put your mind at rest
May want to feed some psyllium for a while just in case, to help "sweep" it out. My friend in Arizona had to do this because the soil is so sandy her horses got sand colic and enteroliths just from grazing.
I would be adding 2 tablespoons of sea salt daily to a feed for the pony. All if mine are fed salt as well as having access to licks. I would also feed psyllium husk for a week every month to ensure no sand build up. Make sure the pony has plenty if forage, I am feeding mine loads of hay which is a first for August as the grass is non existent in my paddocks.