Dr. Valentine, DVM, has been doing research on EPSM, a congenital muscle-wasting disease that has a high relationship with tying up. According to “The Horse” magazine, there is now a simple genetic test that can show whether your horse has this.
Dr. Valentine’s website and a quote from that site about tying up follows, with boldface added by me:
http://www.ruralheritage.com/vet_clinic/epsmlookalike.htm
[I]Tying Up
The exact causes of tying up (known in draft horses as “Monday morning disease”) have yet to be determined, and horses do tie up for reasons unrelated to EPSM. To date, however, examination of muscle biopsies from horses that have tied up, and of diet change in affected horses, indicate that EPSM may be a more common cause of tying up than was previously thought. We have not yet seen a muscle biopsy from a horse that was brought to us for difficult-to-treat tying up that did not show evidence of EPSM.
Any horse that ties up—even if it occurs while an unconditioned horse is being conditioned—should be suspected of having an underlying metabolic problem. EPSM horses may also have decreased blood levels of selenium, but these horses still can have problems, even when selenium levels are corrected. Some EPSM horses have had persistently low selenium levels, even when supplemented at high levels or being given injections. This is not surprising, as selenium needs are greatly increased with exercise or any muscular damage. Selenium levels generally return to normal following diet change for EPSM.
Horse
Beth A. Valentine, DVM, PhD, is involved with EPSM research and other veterinary matters at the College of Veterinary Medicine, Oregon State University.[/I]
