Vitamin E is a vital fat-soluble antioxidant essential for the health of cattle, playing a key role in immune function, muscle integrity, and reproduction. While grazing cattle on fresh pasture typically meet their vitamin E needs, cattle on stored feed require careful management to prevent deficiencies. A vitamin E-deficient diet can lead to health issues such as white muscle disease in calves, reduced fertility in cows and bulls, and weakened immunity. Therefore, knowing what cattle feed has vitamin E and how to supplement effectively is critical for any livestock operation.
Natural Sources of Vitamin E in Cattle Feed
Fresh Forages
The most bioavailable and abundant source of vitamin E for cattle is fresh, lush pasture. The active green leaves of plants contain high concentrations of alpha-tocopherol, the most potent form of vitamin E.
- Alfalfa and Legumes: Fresh alfalfa is an excellent source of vitamin E, often higher in content than grasses.
- Grasses: Actively growing, high-quality grasses also supply ample vitamin E, though concentrations vary based on species, maturity, and growing conditions.
Oilseeds and Grains
Some seeds and their by-products can contribute to the vitamin E content of cattle rations, although levels are often lower and processing can reduce efficacy.
- Wheat Germ: Wheat germ is a notable source of vitamin E, and wheat germ oil is particularly rich in it.
- Whole Soybeans: Contain a moderate amount of alpha-tocopherol, but like many plant sources, levels can vary.
- Distillers Grains: Depending on their oil content, dried distillers grains can provide a modest source of vitamin E.
- Oilseed Meals: Canola and cottonseed meals contain some vitamin E, but the content is generally low compared to fresh forages.
Supplementation Needs for Stored Feeds
The most significant challenge in providing adequate vitamin E to cattle is the rapid degradation of the vitamin in stored feeds. Factors such as oxidation and heat from fermentation dramatically reduce the vitamin content in silage and hay.
- Hay: As forage dries and is stored, its vitamin E content drops considerably. Hay-based diets almost always require supplementation.
- Silage: The fermentation process used to create silage destroys most of the vitamins present in the original forage. Cattle fed a silage-heavy diet are at a high risk for vitamin E deficiency without supplementation.
- Concentrates: While some concentrates like grain mixes may have added vitamin E, the amounts can be variable, and relying on them alone may not be sufficient.
Options for Vitamin E Supplementation
Producers have several options for ensuring their herd receives sufficient vitamin E, especially when green pasture is unavailable.
Feed-Based Supplements
Adding a vitamin premix to a total mixed ration (TMR) or a grain mix is a common and effective method to ensure all animals receive a consistent dose. Water-soluble powder supplements are also available for easier absorption.
Injectable Vitamins
For animals showing signs of deficiency or during stressful periods (like weaning or calving), an injectable vitamin E product may be used for rapid absorption. However, this is typically a short-term solution and does not replace a balanced daily diet. The natural form of vitamin E is more bioavailable than its synthetic counterpart.
Herbal and Antioxidant Blends
Some natural antioxidant products derived from plants can help support the animal's natural antioxidant capacity, potentially reducing the need for high levels of synthetic vitamin E.
Comparison of Vitamin E Sources
| Feed Type | Form | Bioavailability & Stability | Content & Considerations |
|---|---|---|---|
| Fresh Forage | Natural, alpha-tocopherol | High, most available to the animal; highly unstable once cut. | Highest natural source, ideal for grazing cattle. Content decreases with maturity. |
| Hay | Oxidized tocopherols | Low, significantly degraded by drying and storage. | Very low vitamin E content; requires consistent supplementation. |
| Silage | Heavily degraded | Very low, fermentation destroys most vitamins. | Negligible vitamin E content; requires reliable supplementation. |
| Oilseeds (Whole) | Alpha-tocopherol | Good, protected by natural fat. | Variable content depending on the seed; provides "cool energy". |
| Wheat Germ Oil | Alpha-tocopherol | High, but sensitive to heat and processing. | Potent, concentrated source; often used as a direct supplement. |
| Synthetic Supplements | Synthetic tocopheryl acetate | High stability, lower bioavailability compared to natural form. | Stable in premixes; common and cost-effective method of supplementation. |
Managing Vitamin E for Optimal Cattle Health
To effectively manage your herd's vitamin E intake, start by assessing your primary feed sources. If cattle are on a drylot diet consisting mainly of hay or silage, assume they require supplementation. Consult with a veterinarian or nutritionist to determine the appropriate dosage, as requirements can vary based on the animal's stage of life, stress levels, and reproductive status. Monitoring animal intake is also important, especially with free-choice supplements, to ensure proper consumption. A balanced diet, enriched with the necessary vitamin E, is foundational for a healthy, productive herd. For further information, the National Institutes of Health provides comprehensive data on the nutritional requirements of dairy cattle.
Conclusion
While fresh forage is the premier source of natural vitamin E for cattle, reliance on stored feeds necessitates careful supplementation. The vitamin degrades quickly in hay and silage, making added vitamins in grain mixes, mineral supplements, or injectable forms essential to prevent health problems. By understanding the vitamin E content of different feeds and implementing a strategic supplementation plan, producers can maintain the robust immune function, strong muscles, and reproductive performance of their livestock.
