Thiamine Mononitrate (Vitamin B1)

Thiamine mononitrate is a stable, synthetic form of Vitamin B1 (thiamine), commonly used in animal feed and supplements. It plays a crucial role in carbohydrate metabolism, aiding in the conversion of glucose into energy. This vitamin is also essential for proper nerve function, muscle coordination, and overall metabolic health. Horses typically obtain thiamine from their diet through cereal grains, brans, and brewer’s yeast, while microbial synthesis in the hindgut also contributes to their daily needs.

Deficiency of thiamine in horses is uncommon but can occur due to factors such as prolonged antibiotic use, excessive grain intake, or consumption of plants containing thiaminase (e.g., bracken fern or horsetail), which degrade the vitamin. Symptoms of deficiency may include weight loss, muscle weakness, incoordination, and nervous system disorders. Thiamine mononitrate supplementation may be recommended in cases where dietary intake is insufficient or when horses experience stress, intense exercise, or digestive disturbances. Since Vitamin B1 is water-soluble, toxicity is rare, and excess amounts are excreted in the urine.