The Importance Of Iron In Equine Diets

With major minerals, such as calcium and phosphorus, headlining our deficiency concerns for horses, other trace minerals often go forgotten about. Although needed in much smaller amounts, trace minerals are vital to maintain optimum bodily function and play crucial roles in the development of horses. One trace mineral that seems to be on the horse owner’s radar, though, is iron! So, what is the importance of iron in equine diets and should we supplement it?

Why supplement a horse with iron?

Research on racehorse owners in America found that a large proportion of them supplemented their horses regularly with iron. Iron deficiency concerns stem from its function in regulating performance capacity and stamina.

Iron is key for red blood cell health and function, making up around 0.33% of haemoglobin. Haemoglobin is the part of the red blood cell that makes it red in colour but also carries oxygen around the body. Therefore, ensuring optimal iron levels are key for supporting muscle function and energy generation.

Do I need to supplement my horse with iron?

There are very few cases in which a horse becomes deficient in iron and would need supplementation. Due to its vital function in metabolism and energy generation, horses conserve trace minerals quite well.

However, research suggests that some amount of iron may be lost in sweat. It is estimated that horses lose a concentration of around 21 mg/L of sweat. For a horse in extremely hard, who is likely to lose around 25-30 litres of sweat, the iron loss would equate to around 500mg. The great loss in sweat for a horse in extremely hard work or losing a lot of sweat is greater than that of which the body can produce daily. Therefore, iron supplements may be required to ensure that these more athletic horses maintain their levels.

Forage is a great iron source, however as grazing starts to dwindle, the high iron content of forage may be sacrificed. Plus, if you feed a diet high in cereals, you could also compromise your horse’s daily iron intake.

Signs a horse is deficient in iron

While relatively rare, Iron deficiency in horses can still occur, particularly in situations where their diet lacks essential nutrients or they have underlying health issues. Here are some signs that may indicate a horse is deficient in iron:

1. Lethargy and Weakness: Horses with iron deficiency may exhibit general fatigue, reduced stamina, and reluctance to exercise.
2. Pale Mucous Membranes: Check the horse’s gums, inner eyelids, and nostrils. Pale mucous membranes can indicate anaemia, a common consequence of iron deficiency.
3. Poor Coat Condition: A horse’s coat might appear dull, dry, and lacking its usual shine.
4. Reduced Appetite: An iron-deficient horse may show a decreased interest in food.
5. Weight Loss: With reduced appetite, weight loss can occur due to insufficient nutrient absorption and overall health decline.
6. Laboured Breathing: The horse may experience increased respiratory effort, especially during exercise, due to the reduced oxygen-carrying capacity of the blood.
7. Poor Performance: Performance horses may show a noticeable decline in their ability to perform and recover from exertion.
8. Behavioural Changes: Some horses might show signs of irritability or depression.
9. Pica: This is an unusual craving for non-nutritive substances like dirt or wood, which can be a sign of mineral deficiencies, including iron.

To confirm iron deficiency, a veterinarian will typically perform blood tests to measure parameters such as haemoglobin, hematocrit, and serum ferritin levels. The vet may recommend dietary adjustments or iron supplements if an iron deficiency is diagnosed. However, it is crucial to manage iron supplementation carefully, as excessive iron can be toxic to horses.