The effect of an acute angulation of the hind hooves on diagonal synchrony of trotting horses.

The study investigates the impact of altering the angulation of a horse’s hind hooves on its trotting synchrony. The researchers discovered that acute hind hoof angulation, induced by allowing the hind toes to grow longer while keeping the heels shorter, resulted in significant increase in the hind limb breakover time, overreach distance and duration, and changed the limb lift-off sequence.

Research Methodology

• The study used high speed cinematography to record the trotting pattern of sound horses.
• Two farriery (the craft of shoeing horses or the management of horse feet) treatments were analyzed – (1) Normal, where the dorsal hoof wall was aligned with the pastern axis in all feet, and (2) acute hind hoof angulation, where the angulation was lowered by approximately 10 degrees from the normal angle by allowing the hind toes to grow longer than the heels.

Findings and Comparisons

• The study identified that acute hind hoof angulation significantly increased the hind limb breakover time (P = 0.001), overreach distance (P = 0.001) and overreach duration (P = 0.017). This means the horse had to put in more effort and time to lift and move its hind limbs forward.
• There were no changes observed in stride length, forelimb breakover and diagonal distance (P > 0.05), indicating that these aspects of trotting were not significantly affected by the alteration of hoof angles.
• When horses had their hooves trimmed conventionally, the hind limb’s movements were usually slightly off-synchronized with the diagonal forelimbs at the start and end of the diagonal stance phase. In other words, the hind limbs impacted the ground and lifted off slightly before the diagonal front limbs. But with acute angulated hind hooves, the hind limb was more likely to lift off later than the forelimb, showing a significant alteration in limb sequence (P = 0.001).
• The normal coordination between limbs during the swing phase remained unaffected by the acute hind hoof angulation (P > 0.05).

Summary

• Overall, the takeaway from the study is that hoof angulation can significantly impact the trotting dynamics of horses. Lowering the angulation of the hind hooves resulted in changes in breakover times, overreach measures and lift-off sequences.
• Hence, farriery practices should consider these aspects to ensure optimal performance and wellbeing of the horses. More research might be needed to fully understand the long-term impacts of this practice on horses’ locomotion and potential risks of injuries.