Your Guide to Horse Nutrition Minerals

Horse nutrition minerals are an important part of natural horse nutrition. Minerals are needed to help your horse mature, maintain energy and performance, and help prevent health problems.

Horse nutrition minerals means providing your horse with the proper balance of minerals based on their age, weight, and use, and not just guessing at what the right amounts are. Deciphering all of the information out there on this subject can be quite confusing. Hopefully, this information will help you learn about the different minerals, the recommended amounts, why the amounts are important, and how to provide them in your horse’s diet.

What are the different horse nutrition minerals?

There are two types of minerals, macrominerals and microminerals. Microminerals are also called trace minerals. A brief description is provided about the function of each mineral.


  • Calcium (Ca) is important in bone development and maintenance.
  • Phosphorus (P) is also important in bone formation and maintenance.
  • Magnesium (Mg) is important in skeletal development, muscles, and nervous tissue.
  • Potassium (K) is important in maintaining adequate cellular pH.
  • Sodium (Na) has a similiar function as potassium but more important for horses that work hard or sweat alot.


  • Iron (Fe) is important as a part of blood hemoglobin.
  • Zinc (Zn) is important in bone development, healthy hooves and coat, and reproduction.
  • Manganese (Mn) is important in cartilage and bone development and mineral utilization.
  • Copper (Cu) is important in bone and cartilage development and iron utilization.
  • Iodine (I) is important in the production of the hormone thyroxine.
  • Cobalt (Co) is important for the synthesis of vitamin B12.
  • Selenium (Se) is important to reproduction, growth, and the immune system.

What are the nutritional requirements of horse nutrition minerals?

In 1989, the National Research Center (NRC) published their recommendations on equine nutrient requirements. The NRC recommended a mature 1,000 lb. horse at maintenance receive the following daily mineral amounts; percentages are notated after the daily amounts:

Potassium 23g .30%
Calcium 18.1g .24%
Phosphorus 12.7g .17%
Sodium 7.5g .10%
Magnesium 6.8g .09%
Iron 300mg 18.14mg/lbs
Zinc 300mg 18.14mg/lbs
Manganese 300mg 18.14mg/lbs
Copper 75mg 4.54mg/lbs
Iodine .8mg .05mg/lbs
Cobalt .8mg .05mg/lbs
Selenium .8mg .05mg/lbs


To find out more about the recommendations of horse nutrition minerals, please click here for more up to date information. Remember that the requirements will vary based on your horse’s age, weight, and use.

How important are the amounts of horse nutrition minerals?

While your horse receives some minerals from hay and grain, you should have your hay analyzed to help you determine what minerals and amounts are truly needed. Your county or state agricultural office can test your hay. The National Forage Testing Association can help you locate a lab near you if you are unable to find one. Phone: 402 333-7485; E-mail: NFTA@TCONL.COM; website: The following is information about health problems that can arise from mineral deficiencies and overdoses:

  • potassium deficiency can result in a decreased appetite, weight loss, and fatigue. Too much can effect your horse’s heart.
  • calcium or phosphorus deficiency can result in rickets and fragile bones in foals and lameness and fractures in mature horses. The calcium and phosphorus ratio should always be 1.5:1 to 2:1 because bones will be weakened if your horse receives more phosphorus than calcium.
  • sodium deficiency can result in a decreased appetite and water consumption and dehydration.
  • magnesium deficiency can result in muscle tremors and nervousness.
  • An iron deficiency can result in a weak or anemic horse, though a deficiency related to the diet has reportedly not been found in a horse. Too much iron may affect the other minerals or possibly result in death.
  • zinc deficiency can result in a decreased appetite and reproductive, growth, and hoof/coat problems. Too much zinc may result in developmental leg disorders.
  • manganese deficiency can result in cartilage and bone problems in growing horses.
  • copper deficiency can result in developmental bone disorders and anemia. Some owners have given their mares amounts above the NRC recommendation and have seen reduced bone and cartilage problems in their foals.
  • An iodine deficiency can result in mares that are unable to regulate their cycles and give birth to foals that are weak or stillborn. It can also result in goiter.
  • cobalt deficiency can result in a vitamin B12 deficiency and anemia, but this is rare in horses.
  • selenium deficiency can result in muscle disorders in foals and adults. Too much selenium can result in abdominal pain, diarrhea, blindness, lethargy, and in chronic cases, hair loss and signs of laminitis.

What horse mineral supplement is right for your horse?

No mineral supplement is right for every horse because the natural horse minerals and their amounts vary in pastures and hay, even those of the same kind. You need to determine how much hay and grain your horse eats, the mineral amount in each based on the amount eaten, and then see what minerals and amounts your horse is lacking. Then, do your shopping for a mineral supplement that comes closest to the recommended amounts. Just remember that horse nutrition minerals are important for your horse’s health and it will take some research to determine what is the best supplement for your horse.

What about free choice horse nutrition minerals?

Some horse owners like to give their horses the opportunity to choose what minerals they want by offering them free choice. If this is something you are interested in, Advanced Biological Concepts (ABC Plus) offers free choice vitamins and minerals.

Are there any natural sources of horse nutrition minerals?

Spirulina is a natural source of calcium, manganese, iron, chromium, phosphorus, molybdenum, iodine, chloride, magnesium, sodium, zinc, potassium, selenium, germanium, copper, and boron. Click here to learn more about the benefits of spirulina.
Bee pollen is also a source of calcium, phosphorus, potassium, sulphur, sodium, chlorine, magnesium, iron, manganese, copper, iodine, zinc, and boron. Click here to find out more about the benefits of bee pollen, another natural source of horse nutrition minerals.

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