Selenium Toxicity and Deficiency- Tieing Up

Selenium, in conjunction with vitamin E, is necessary for proper functioning of the immune system and to protect the integrity of cell membranes. However, there is a delicate balance between too little selenium and too much. Selenium is a mineral found in the soil in many areas of the country. Horses normally ingest selenium while foraging. In other areas--the Midwest for example--selenium is deficient in the soil, and without proper supplementation horses can have significant problems. Selenium deficient horses will often ´tie-up,´ a degenerative condition of the muscles also known as rhabdomyolysis. It can affect the heart muscle,the muscles of respiration, as well as the large muscles of the back and limbs. It can also cause a decrease in the efficiency of the immune system, leading to opportunistic infections.A horse that has rhabdomyolosis will have severe muscle cramps resulting in sweating, stiffness, and increased pulse. The breakdown of muscle cells can result in coffee-colored urine. The most common obvious symptom is repeated "stretching" to urinate. Do not walk a horse that is tied up. CALL YOUR VET IMMEDIATELY A free-choice salt/mineral mix containing selenium is the safest form of supplementation but more radical supplementation is available in acute cases in the form of an injection.