Scientists at the University of Georgia’s College of Veterinary Medicine are studying a new diagnostic test that will detect a common disease of the musculoskeletal system of the horse before he exhibits lameness or other performance problems. The test will detect excess accumulation of proteoglycans–molecules that help organize connective tissue so that it is elastic, yet strong–and thus catch equine systemic proteoglycan accumulation (ESPA) before it debilitates the horse.

The test involves microscopic examination of a thin sliver of tissue, about the size of a human fingernail, from the nuchal ligament (at the back of neck).

A: Photomicrograph of normal nuchal ligament shows uniformly stained (pink) connective tissue. The small blue dots are nuclei of fibroblasts, the main cells of connective tissue. B: Photomicrograph of nuchal ligament from a horse affected with ESPA. Small pools of light blue staining indicate excess proteoglycans (marked with arrow). IMAGES COURTESY BMC PAPER AND DR. JAROSLAVA HALPER

Jaroslava Halper, MD, PhD, lead author on the paper, says, “Researchers originally identified and determined that the disorder affected only the suspensory ligament because the number one clinical sign for this disorder is lameness.” In some severe cases, horses might even have hyperextended fetlocks