Previous studies have shown that bones develop to suit the purpose routinely required of them; therefore, would young horses in regular work from the time they are foals have stronger musculoskeletal tissues then those left to mature in pasture? Chris Kawcak, DVM, PhD, Dipl. ACVS, and the Global Equine Research Alliance researched this issue. Kawcak presented their findings regarding osteochondral tissues at the 15th Annual Kentucky Equine Research Conference.

The group divided 33 Thoroughbred foals into exercise and pasture groups. The exercise group was conditioned five times per week from ten days to 18 months of age, increasing the speed of the workouts over time as the foals grew. This group of foals was turned out in pasture when not in work. The other group also grew up in a pasture environment, but was not asked to work.

Study results were mixed. The researchers used a technique called confocal laser scanning microscopy, which scanned the horizontal layers of cartilage and showed live and dead cells as points of different color. This technology showed that the horses in the exercise group had 14% more viable cells on the surface of the cartilage in the fetlock joint, which was the area under scrutiny in this study. However, this difference in cell makeup did not appear to have any effect on the cartilage’s function or structure.

While the data on osteochondral tissues did not show a strong trend for or against early exercise, the research did reveal an anatomical anomaly that could be a major factor in catastrophic injuries