Zinc (Zn) is an essential trace mineral that is required in the horse’s diet to support the proper function of many enzymes and proteins. It is involved in antioxidant protection, immune function, protein synthesis, and cellular communication.
Zinc is also important for proper bone development in foals and supports healthy hooves and skin. It is critical for reproductive health and supports normal growth and tissue health.
Zinc is commonly fed to horses that are easy keepers or horses with metabolic issues. Zinc can support healthy blood sugar levels by improving insulin sensitivity and boosting antioxidant status which might be lacking in horses with EMS.
It is important to balance levels of copper, iron, and zinc in your horse’s feeding program. High iron can interfere with copper and zinc absorption from the gut, causing your horse to develop signs of deficiency even if these minerals are fed at adequate rates.
Wheat bran, wheat middlings and brewer’s grains are good sources of zinc in the equine diet. Most forages are low in zinc, particularly if they are grown in areas with low levels of this mineral in the soil. Horses that are on forage-only diets are likely to require supplementation.
Mad Barn’s Omneity mineral and vitamin supplement provides zinc in a balanced formula designed to meet the core nutritional needs of the majority of horses. You will also find zinc in our AminoTrace+ mineral and vitamin formulated specifically for metabolic horses.
We also carry bulk Bioplex Zinc powder and a 3:1 Zinc Copper supplement in the recommended ratio for these minerals.
The feeding rate for zinc depends on your horse’s individual requirements and current diet. To determine the appropriate supplementation rate for your horse, submit your horse’s diet for analysis and one of our nutritionists will provide a complementary review.
Benefits of Zinc for Horses
Zinc is a co-factor for hundreds of enzymes in the horse’s body affecting a diverse range of physiological functions. Enzymes are proteins that carry out reactions in the body, such as breaking down sugars and fats for energy.
As an enzyme co-factor, zinc is required to help catalyze many biochemical reactions. This is why zinc supports so many functions in the body from antioxidant protection to hoof health and coat quality.
Zinc is the second-most abundant trace mineral in horses behind iron. It is found in all cells and tissues with the majority (80-85%) found in skeletal muscle and bones.
Below are the top 10 reasons why horses need adequate zinc in their diet:
1. Antioxidant Protection
An important function of zinc is to support antioxidant defenses. Both copper and zinc are found in a key antioxidant enzyme, superoxide dismutase (SOD). Zinc is also involved in regulating the production of other antioxidant enzymes. [2]
These enzymes converts harmful oxidants or free radical particles into neutral, harmless compounds. Free radicals are produced naturally by cells when nutrients are broken down for energy, but over time they can cause damage to cells.
By improving antioxidant status, zinc protects against premature aging and supports healthy tissues and cells. Horses that are heavily exercised produce more harmful oxidants and could benefit from additional antioxidant support.
In a research study, heavily exercised Thoroughbreds were fed an antioxidant supplement containing zinc and copper. The horses on the supplement experienced improved antioxidant capacity during the training period. [3]
Senior horses also tend to have lower levels of antioxidant enzymes and may benefit from zinc supplementation.
2. Hoof Health
A proper balance of zinc to copper helps support keratin synthesis. Keratin is the main protein in hooves that creates a strong hoof structure.
Horses meeting their zinc and copper requirements have lower risk of white line disease (also known as seedy toe) and lower incidence of hoof wall separation. [4]
3. Immune Function
Zinc helps immune cells respond to infections. When infection is detected, zinc levels in the blood drop as this mineral is taken up by immune cells and the liver. The temporary decrease in blood zinc during infection has been shown in horses affected by fever and cellulitis. [5]
Zinc enables immune cells to send out signals to other cells to coordinate an immune response. These immune signaling molecules are known as cytokines.
More research is needed to determine whether supplementing horses with zinc while they are fighting an infection is beneficial. It is theorized that adding zinc to diets that are otherwise low could improve the immune response.
4. Skin Health
Zinc deficiency in horses can cause skin abnormalities such as slow wound healing. This may be attributed to a weakened immune system.
Horses with low zinc might be more susceptible to mud fever or rain scald – a type of bacterial overgrowth on the skin that occurs in damp conditions. If immune function is impaired because of low zinc, the skin can become overwhelmed by bacteria.
Having adequate levels of zinc in the diet can support healthy skin and improve coat quality and sheen.
5. Insulin Levels and Insulin Sensitivity
In other animals including humans, low levels of zinc in the blood are associated with insulin resistance and diabetes. This mineral affects insulin secretion from cells in the pancreas. It may help ensure the right amount of insulin is released to manage blood sugars. [6]
Zinc is also involved in maintaining insulin sensitivity. This refers to how well cells respond to insulin to move glucose out of blood. In humans, zinc supplementation has been shown to improve insulin sensitivity in obese people. [7]
Zinc’s affect on insulin sensitivity has not been directly studied in horses. However, zinc is crucial for supporting antioxidant status and oxidative stress is a key contributor to insulin resistance. Ensuring adequate zinc intake may reduce the risk of metabolic dysfunction.
It is especially important that easy keepers and horses with equine metabolic syndrome or Cushing’s/PPID meet their zinc requirement to support proper insulin action.
6. Joint Health
Zinc is required to make the protein collagen which is a major part of tendons and ligaments in joints. It is also required for cartilage production.
In one study, moderately exercised yearlings were supplemented with a blend of copper, zinc, cobalt and manganese in either organic or inorganic forms. After 12 weeks, the horses fed the organic minerals had higher levels of markers for collagen synthesis.
These horses may be able to maintain heavier work loads and may be less susceptible to wear and tear in their joints. [8]
This study also shows that organic trace minerals are better able to support collagen production in joints than inorganic minerals. This study utilized zinc methionine as an organic source of zinc.
7. Coat Quality and Pigmentation
Zinc is involved in making the protein keratin which is the most abundant protein in hair. Keratin is responsible for giving hair its structure.
Horses supplemented with organic forms of zinc and copper had stronger and more elastic hair fibres than those given inorganic forms of these minerals. [9]
Zinc is also a component of the enzyme tyrosinase which makes melanin – the pigmentation protein that give skin and hair its colour.
Horses with dull, faded and frizzy hair might be low in zinc and might not be making enough melanin. Deficiency is most noticeable in chestnuts, bays, and blacks who require more melanin for their dark coat colour. These changes in coat colour and quality can also be a sign of copper defici