Salt

What it is

Salt is sodium chloride (NaCl), and horses' sodium and chloride needs are usually met as salt ^[1].

Getting enough

Most concentrates don't supply enough salt and forages contain little sodium, so free-choice salt is recommended ^[1]. Voluntary intake varies widely between individuals: from 19 to 134 g a day in one study ^[1].

Horses sweat heavily and their sweat is hypertonic: more than 30 g of salt can be lost in 1–2 hours of hard work ^[1]. Horses worked hard in hot weather, or fed salt-deficient rations, are the most likely to show signs of salt deficiency ^[1].

Too much

Stabled horses may eat extra salt, which increases drinking and urination but generally does no harm if forage and water are adequate ^[1]. Salt poisoning is unlikely unless a salt-deprived horse suddenly gets free access, or salt is force-fed without water ^[1].

Forced oral salt pastes can cause abdominal discomfort and may aggravate gastric ulcers unless given with food or diluted, and prolonged forced supplementation can impair the horse's ability to adjust to losses ^[1].

Reading it on a label

A label may state salt, sodium or both. They aren't the same figure, because salt is sodium chloride ^[1].

See also sodium, chloride, potassium.