Nutritional and Technological Additives – What’s Truly Necessary and What to Avoid
Key Points at a Glance
- Two main categories: Nutritional additives (vitamins, minerals) vs. technological additives (processing, preservation, appearance, and smell)
- Mandatory declaration: All additives must be listed by name and registration number
- Natural supply often insufficient: Hay and grass alone do not always meet the full nutritional needs of domestic horses
- Dosage is crucial: Too little has no effect, too much can cause harm – the dose makes the poison
- Synthetic doesn’t mean bad: Synthetic vitamins can even be more bioavailable than natural ones
- Preservation is often necessary: Without technological additives, feed would spoil quickly and become unsafe
- Transparency signals quality: A complete list of all additives is a sign of a reputable manufacturer
Additives are one of the most hotly debated topics in horse nutrition. Some see them as essential tools for optimal nutrient supply, while others condemn them as unnecessary chemicals. As so often, the truth lies somewhere in between—and depends entirely on which additives are used and why.
Understanding the System of Additive Categories
Knowing the Legal Classifications
Feed legislation divides additives into clearly defined categories. This classification is not arbitrary but based on the specific function each additive has in the feed. Every approved additive receives a unique registration number that identifies its properties and purpose.
Nutritional additives compensate for nutrient deficiencies or improve nutrient utilisation. They are essentially the “dietary supplements” of feed and are often indispensable for optimal nutrition.
Technological additives serve manufacturing, preservation, or improving the physical properties of feed. Without them, many feeds would spoil quickly or be refused by horses.
Sensory additives influence the appearance, smell, or taste of feed. They are used less often in horse feeds than in pet food for dogs and cats, where they are sometimes referred to as “attractants.”
Zootechnical additives aim to enhance performance or animal well-being. These include probiotics or enzymes—an area that overlaps with “nutraceuticals,” feed substances that almost act like pharmaceuticals in terms of health effects.
Nutritional Additives in Detail
Vitamins – The Invisible Helpers
Vitamins are often indispensable in horse nutrition, as natural feed components do not always provide adequate levels. Many vitamins degrade in stored hay, and horses without pasture access—whether due to space limitations or health reasons—miss out on valuable vitamins supplied by fresh forage.
Vitamin E (alpha-tocopherol) is essential for muscle metabolism and the immune system. Registered as 3a700, it is usually produced synthetically because natural vitamin E is far more expensive and less stable. Sport horses have increased requirements that cannot be met through forage alone.
Vitamin A (retinyl acetate) supports vision, immunity, and reproduction. Declared as 3a672a, it is especially important for horses with little or no access to fresh forage.
B vitamins are largely produced by hindgut microbes but not always sufficiently—especially in horses suffering from gut dysbiosis. All B vitamins are water-soluble, meaning oversupply through supplementation is unlikely.
Vitamins C and D are synthesized by horses themselves and generally do not need to be added to feed. In growing horses, care must be taken not to oversupply vitamin D, as excess amounts negatively affect bone metabolism.
Trace Elements – Small Amounts, Big Impact
Trace elements are vital in tiny quantities but toxic when overdosed. Correct dosing is especially critical.
Zinc, listed as 3b603 (zinc oxide) or 3b605 (zinc sulfate), is essential for skin health, immunity, and wound healing. Deficiency often shows as poor hoof quality or skin issues.
Copper (3b405, copper sulfate) is important for iron metabolism and pigmentation. Deficiency may cause anemia and pale circles around the eyes (“copper glasses”). Copper is toxic in excess—precise dosing is legally required.
Selenium, listed as 3b801 (sodium selenate) or 3b815 (selenium yeast), has a narrow margin between deficiency and toxicity. Deficiency weakens immunity and can cause muscle damage; excess leads to hair loss, blindness, and coordination issues. Organic selenium is particularly critical because it accumulates in tissues and is released slowly. Links between organic selenium and conditions such as acute EOTRH, tendon and ligament issues, white line disease, laminitis predisposition, and insulin resistance are under discussion. Inorganic selenium is therefore preferred.
Iron is often added unnecessarily. Most horses receive enough iron from forage. Organic iron (chelated) cannot be excreted and may cause liver failure over time.
Iodine, listed as 3b201 (calcium iodate) or 3b202 (potassium iodide), is essential for thyroid and energy metabolism. Some countries or regions are largely iodine-deficient, making controlled supplementation sensible.
Cobalt (3b304, cobalt carbonate) is needed for vitamin B12 synthesis in the hindgut. Deficiency is rare; overdose may cause heart or thyroid problems.
Manganese, listed as 3b502 (manganese oxide) or 3b503 (manganese sulfate), is important for bone formation, cartilage metabolism, and fertility. Because it naturally occurs in high quantities in hay, supplementation is seldom necessary.
Technological Additives – The Invisible Helpers
Preservatives – Protection Against Spoilage
Without preservatives, long-lasting feed would not be possible. When porous grain flakes (e.g., barley flakes, puffed corn) are used, it is safe to assume the feed has been treated to prevent microbial spoilage.
Propionic acid (1k280) and its salts prevent mold growth and are crucial in moist feed components. They are also used to preserve hay bales with high moisture content. Unfortunately, horses—especially those with gastric issues—often tolerate propionic acid poorly.
Formic acid (1a236) has antibacterial effects and is common in organic products. It is less controversial but still problematic for sensitive stomachs.
Citric acid (1a330) and its salts are natural antioxidants and preservatives and are generally considered safe.
Antioxidants – Protection Against Rancidity
Fats and oils quickly turn rancid without antioxidants and can become harmful. Oily components such as seeds and meals pose the same risk. Therefore, most mixed feeds contain antioxidants—though they are only required on the label above certain thresholds. If a feed contains oils, brans, meals, or extraction meals, it can be assumed that without antioxidants they would already be rancid.
Tocopherol extract (1b306) is vitamin E and an excellent antioxidant; preferred by many manufacturers.
BHT (1b321) and BHA (1b320) are synthetic antioxidants—very effective but controversial. They are considered safe at approved levels but avoided by some consumers.
Ascorbic acid (vitamin C, 1a300) is a safe antioxidant but less effective than specialized alternatives.
Binders and Processing Aids
Diatomaceous earth (1m558i) is used as an anti-caking agent for powdered feeds. It is natural and harmless.
Lignosulfonates (1c730) improve pellet quality and reduce dust and breakage; harmless at typical levels.
Lecithin (1c322) works as an emulsifier and can improve fat absorption. As a natural component of cell membranes, it is safe.
Identifying Problematic Additives
Unnecessary Additions
Flavorings are usually unnecessary in horse feed and are most commonly found in treats (“strawberry-cream flavor” or “blueberry taste”). While flavorings are less problematic for blood sugar levels than hidden sugars used as appetite stimulants, they can mask feed refusal—an important indicator of dental issues, digestive problems, or stomach discomfort.
Colorants serve only visual appeal and have no benefit for the horse. They are mainly aimed at the owner, whose eye “eats as well.” They may cause allergic reactions and are a clear sign of marketing rather than quality.
Sweeteners such as saccharin promote sugar habituation and are unnecessary if the feed contains high-quality base ingredients. In pig fattening, sweeteners are used because they increase appetite—precisely the opposite of what is desirable for most horses.
Avoiding Overdosage
More is not always better—especially with trace elements. Overdosing can quickly become harmful. Reputable manufacturers follow scientific nutrient guidelines and dose accordingly. Problems arise when horse owners combine multiple feeds to create their own “custom mix.” In these cases, it is essential to calculate all additives across all feeds based on the final daily ration, to avoid both excess and deficiency.
Natural Versus Synthetic
Bioavailability Matters Most
The origin of a vitamin says little about its effectiveness. Synthetic vitamin E, for example, is just as effective as the natural form but far more stable and affordable. Natural vitamin E from plant oils may sound “healthier,” but it is more expensive and less shelf-stable.
Organic trace elements (chelates, protein-bound forms) are often more bioavailable than inorganic salts, but also more expensive. They are the better choice for proven deficiencies in zinc or copper. However, in mixed feeds, mineral supplements, or in cases of general deficiency, they should be avoided because some organic forms are difficult or impossible for the body to regulate (e.g., organic iron or selenium).
Seeing Through Marketing Myths
“Free from artificial additives” sounds healthy but is often misleading. Horses need specific nutrients that are not present in sufficient quantities in natural feed ingredients alone. Feeding without any additives can lead to deficiencies. It is absolutely appropriate to provide a mineral supplement with trace elements or vitamins—even though these legally count as “additives.” But the same rule applies here as always: pay attention. Not all additives are necessary or healthy, and the dose makes the poison.
Quality Manufacturers and Their Additive Policies
Transparency as a Mark of Quality
High-quality manufacturers like OKAPI list not only mandatory additives but also those that do not require declaration. This creates transparency and prevents unpleasant surprises—for example when a horse has intolerances or allergies to certain additives. Good manufacturers also prefer natural preservatives and avoid unnecessary flavorings or colorants. They dose according to scientific recommendations, not marketing trends.
Warning Signs in Additives
- Extremely long lists with many different additives may indicate an attempt to improve a low-quality base mix with supplements.
- Unusually high dosages—especially of trace elements—are concerning. More is not always better.
- Many flavorings or taste enhancers suggest that the feed is not palatable on its own and likely contains low-quality components.
Practical Evaluation of Additives
When reviewing an additive list, consider:
Are all important basic nutrients covered?
Is the dosage appropriate and need-based?
Are unnecessary additives included?
Is the declaration open and transparent?
Evaluating Price–Performance
Additives cost money—but the right ones can save veterinary costs in the long run. A feed with high-quality, appropriately dosed additives may rightly be more expensive than one with low-quality or no additives. Cheap feeds without additives are often not cost-effective if you then need to buy mineral supplements or individual nutrients separately.
Understanding and Evaluating Additives Correctly
Additives are neither inherently good nor inherently bad. What matters is why they are used and how appropriately they are dosed. Blanket condemnation of “chemicals” in feed is no more helpful than blindly accepting all additives as beneficial.
Quality-conscious horse owners should scrutinize the additive list just as critically as the ingredient list. The rule is:
Transparency beats marketing.
Function beats emotion.
Correct dosage matters more than ingredient origin.
Those who understand which additives are used and for what purpose can make informed decisions and ensure optimal nutrition for their horses—without unnecessary fear of “chemicals” and without naïvely trusting anything labeled “natural.”
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