The 14th annual Bluegrass Laminitis Symposium, hosted Jan. 25-27 by R.F. (Ric) Redden, DVM, and his wife, Nancy, of the International Equine Podiatry Center, unveiled many recent advances in the mechanisms of laminitis, navicular disease, and various shoeing and trimming methods.

This year, symposium attendees were treated to seminars on wild horse foot physiology and four-point trimming with Redden; new information on hoof microanatomy and laminitis trigger factors with Chris Pollitt, BVSc, PhD; biomechanical analysis of hoof and limb forces with Alan Wilson of the Royal Veterinary College in England; laminitis prognosis and pain management with David Hood, DVM; radiographic and photographic techniques, and much more.

One of the biggest revelations of the symposium was Pollitt’s presentation on his laminitis work at the Australian Laminitis Research Unit, in which he discussed carbohydrate overload-induced laminitis. It seems likely that carbohydrate overload provides an very favorable environment for Streptococcus bovis bacteria in the hindgut, in which case its population explodes (doubling about every 12 hours). With this abnormally large bacterial population, Pollitt theorizes that the bacterial toxin weakens the mucosal barrier of the gut, allowing the toxin to reach the bloodstream and thus the feet, where it activates enzymes that degrade the laminar attachment of the hoof to the foot in vitro. Pollitt has found that virginiamycin antibiotic administered before carbohydrate overload prevented laminitis in many cases, and that some enzyme inhibitors minimize the damaging effects of the S. bovis-activated enzymes.

"Perhaps this is why it’s eluded us for so long," Pollitt concluded. "It looks like a normal process that has gotten thrown out of balance