The thyroid gland, anatomically tiny when compared to the size of an average horse, is housed within the upper neck, embodying two lobes located on either side of the windpipe. Though the thyroid gland is small, its functioning capabilities are an example of grandeur in nature. Hormones released from the thyroid gland influence:
• body temperature
• protein and calorie use
• heart rate and strength
• red blood cells
• hair coat
• energy levels
• nerve and musculoskeletal development in foals
An imbalance of the key nutrients required to sustain a healthy thyroid may create thyroidal dysfunction. One such nutrient is iodine. Insufficient amounts of iodine reduce the capability of the thyroid gland to furnish its needed hormones for body function and communication. Knowing this, our initial thought process is to run to the feed store to purchase iodine and then add it to the feed bucket, right? Wait! Too much iodine, or supplementing a thyroid hormone, will have the same ill eff ects as not having enough. Evaluate your feeds, hay and supplements prior to adding iodine to your horse’s diet.
Further influence of nutrition and metabolism on the thyroid gland is the absorption of one nutrient in relation to another. Consider the relationship between iodine and calcium. On the “Mineral Wheel,” you’ll see that iodine has four lines panning out from it. Each line symbolizes a relationship between the two connected nutrients. The direction of the arrow indicates a need of that nutrient for absorption, meaning that calcium is required for absorption of iodine, yet excess will inhibit absorption. As such, some horses exhibiting symptoms of thyroid dysfunction may have a diet that is too high in calcium, not deficient in iodine.
Balancing these and other primary nutrients is imperative to the thyroid gland and the body as a whole. Thyroid hormones serve as catalysts in the movement of calcium from the blood stream for storage in the bones: hormones from the parathyroid glands are responsible for the appropriate release of this stored calcium back into the bloodstream.
If you determine that iodine is a possible deficiency in your horse’s diet, consider an avenue of nutrient support before incorporating a thyroid hormone. Once a hormone is introduced into the body, it is possible for the body to become dependent upon that supplementation, increasing probability of suppressing normal thyroid function. Prior to hormonal intervention, offer your horse, in a free choice format, kelp, mineral or sea salts, iodized salt, or a proprietary blend, in conjunction with non-mineralized salt. Herbal blends and essential fatty acids may be considered as positive additions to the ration as well.
When contemplating the needs of the thyroid and the inter-relationship among all nutrients, these should also be considered:
• beta carotene
• L-Tyrosine (amino acids)
• niacin and B12 (in form of vitamin B complex)
• vitamins A, C, D and E (antioxidants)
If you are consistently confronting unresolved health issues in your barn, it is a good idea to have your water tested. Water is an integral part of both nutrition and metabolism. It carries nutrients to the cells and removes waste. Water constitutes 70-75% of the body and 80% of the blood. Horses’ environments are becoming more prevalent within metropolitan areas, where water sources are often treated with chlorine, fluoride and/or sodium via water softeners. Rural areas battle hardness, water containing high levels of minerals and iron.
Chlorinated water is detrimental to iodine activity as chlorine is an iodine blocker, reducing the body’s ability to utilize iodine. Reviewing the mineral wheel again, note that fluoride may interfere with iodine absorption also. Incorporation of water softeners increases sodium content, therefore creating an imbalance of sodium to potassium in the body. The relationship between sodium and potassium, the sodium-potassium pump, is crucial to metabolic processes and nutrient transfer within the body.
Other situations that may affect thyroid function are liver toxicity, dosing of phenylbutazone, and ingestion of endophyte-infected fescue. Diets high in estrogenic food sources can create thyroid hormone imbalance, therefore it is essential for natural estrogen sources to be in balance.
Diagnosing a thyroid condition is difficult. Research indicates that testing for certain levels of hormones may be inaccurate for various reasons. Discuss possibilities with your veterinarian, nutritionist and health care provider. Keep your focus on the animal as a whole, not condoning “single factor mentality” or supplementing single nutrients. The body works as a cohesive unit and the diet is an integral part of maintaining that cohesiveness and balanced symmetry.
Kendra Helfter is the President of Helfter Enterprises Inc., dba Advanced Biological Concepts, Osco, IL. Helfter Enterprises, Inc. was founded to develop nutritional technology for the prevention of disease. Advanced Biological Concepts is a manufacturer of natural and organic feed supplements and nutritional additives. The company works hand-in-hand with holistic veterinarians and practitioners to address current health concerns. www.abcplus.biz