Horses have a metabolic need for all known vitamins and minerals. If adult horses receive cereals and high quality feed, the tissues are synthesized in sufficient amounts of ascorbic acid, and other water-soluble vitamins (except biotin and possibly thiamin) and vitamin K are present in sufficient amounts. they are synthesized in the gut micro-flora and are absorbed. Thus, the nutritional requirements apply to vitamins A, D and E, biotin and possibly thiamin.
Cereals and feed intended for horses must be produced under good animal husbandry conditions, harvested without microbial and other damage, properly stored and up to 2-3 years of age. If horses have to rely on root vegetables and poor quality feed, other vitamins will be needed in the diet for optimum performance.
Young foals need a source of cyanocobalamin (B12), which is usually obtained from the milk of the dam, and the premature separation of the foals must be an additional source of B vitamins. Vitamin A supplementation is required for all horses if the feed does not contain enough carotene. The horse converts the mixed carotenes of grass and clover into vitamin A (about 40 g of carotene-A). Vitamin D2 or D3 supplementation is required if the feed is artificially emptied or if the horses are kept for a long time.
Vitamin D supplementation is required outside moderate widths or at high temperature latitudes. Horses containing tropical feed containing significant amounts of oxalate (more than 5 g total oxalate, 0.5: 1 Ca: oxalate ratio) require additional dietary supplements. In case of suspicion of mineral problems, the amount of digestible Ca and P is the minerals that are likely to be defective. Horses that produce dry matter at least half a good quality leafy feed at moderate latitudes with cereals do not require mineral supplements.
Exception, where horses have been worked hard, especially in hot weather, when they require additional sodium chloride. In some places, soils, fodder and other plants contain inadequate copper, selenium or iodine and need to be supplemented. In some regions, soil contains toxic amounts of selenium and plants grown on such soils cannot be used for horses.
Some past species absorb certain heavy metals (eg cadmium) through roots. Such pastures and herbs can be harmful.
The daily digestible energy requirement for maintenance can be estimated from Equations 1 and 2. This requirement is directly proportional to body weight, and in the case of horses ranging from 125 kg to 600 kg, the requirement corresponds to the relationship.
In the case of horses weighing more than 600 kg, physical activity is generally. The nutritional need of the protein suggests that the protein comes from proper digestibility, grain cereals, and protein-rich foods with a reasonably high biological value (BV). With this assumption, the mixture BV should be appropriate. When root vegetables are used, the poorly essential amino acid equilibrium protein concentrates, lysine and possibly the threonine content of the diet.