Vitamins for Yearling Clydesdale Horses

The Clydesdale is a heavy draft horse originating from Lanarkshire in Scotland. A powerful horse dating back to the early 19th century, it was bred for agricultural and mining work. At maturity, the Clydesdale weighs up to 2,200 pounds. A yearling has completed about 60 percent of its growth; another 20 percent of growth will take place before it is 24 months old. It is important that a horse this age receives the vitamins it needs for growth.

Vitamin A

Vitamin A, part of the fat-soluble group, must be part of a Clydesdale's diet. Vitamin A contributes to vision, immunity, red blood-cell production, growth and development, particularly bone growth. Good natural sources include carrots and green, fresh grass.

A 1,200-pound Clydesdale yearling, which is slightly bigger than other breeds, requires about 24,000 international units (IU) of vitamin A every day. Three carrots contain that amount.

Vitamin D

Vitamin D, crucial to proper growth, aids absorption and transportation of calcium and phosphorus, two minerals necessary for growth and development. Because vitamin D is synthesized on the skin by sunlight, horses such as Clydesdales with thick hair may not get enough. Sun-cured forage contains the vitamin but its levels in dried hay decrease over time. Adding a fish-oil supplement in accordance with manufacturers' instructions will ensure adequate levels. An overdose of vitamin D can cause calcium deposits in soft tissue.

A Clydesdale yearling needs about 10,650 international units daily.

Vitamin E

Vitamin E is essential for growth, muscle development and function, oxygen transport and red blood cells. An important antioxidant, it is useful for the immune system. A deficiency can result in muscle loss and lack of coordination.

A 1,200-pound Clydesdale yearling needs about 1,050 international units daily. Natural sources include fresh grass and wheatgerm; vitamin E is also present in sunflower oil.

Remaining Vitamins

Other vitamins necessary for overall health include fat-soluble vitamin K, essential for blood clotting. According to Karen Briggs, author of "Understanding Equine Nutrition: Vitamin Function," no ideal level of vitamin K has been established, but access to pasture or quality hay provides adequate amounts.

Water-soluble vitamins C and the B group can be synthesized within the body. Deficiency is rare in horses because adequate levels are available in their food.