Zinc deficiencies can retard protein metabolism and restrain amino acid utilization, both necessary for hoof condition and repair. Most equine rations need zinc supplementation in order to meet basic requirements. Copper deficiency in horses causes a number of abnormal conditions including the defects in the pigmentation and structure of the hair and hoof. The recommended levels of Copper supplementation is 25 mgs. per day. Another essential mineral is iodine, which is important to the metabolic function of the horse.
Iodine deficiency is apparent in dull lusterless hair coat and poor hoof condition.
The recommended level of Iodine for horses is 1 mg. per day. Of those eight, only lysine and methionine are related to hoof growth in livestock. Lysine, the more important of the two, is the key to improving protein availability. Grass hay diets are especially lacking in lysine. Most typical equine diets have a shortfall of roughly 750 mgs.