Question: what is the best vitamin and mineral supplement for horses?
Answer: Vitamin K. ... 
Copper. ... 
Iron. ... 
Selenium. ... 
Iodine. ... 
Cobalt. ... 
Manganese. Manganese is required for carbohydrate and fat metabolism and also has a role in the production of joint cartilage.
Zinc. Zinc is an important co-factor in many enzyme reactions in the body and has a particular role in skin health and wound healing.