Investigation of forelimb hoof wall strains and hoof shape in unshod horses exercised on a treadmill at various speeds and gaits.

This study examines the effect of moderate regular exercise on the strain and shape of the hoof wall in the forelimb of unshod horses, by testing six horses on a treadmill at varying speeds over a four-week period. It shows that the strain increased during the stance phase of the stride, and was dependent on the site of the hoof and gait used, and also that no relationship between changes in toe angle (TA) and hoof wall strains could be established. The hoof circumference showed no alteration in response to exercise.

Research Methodology

• Six horses of varying body types were selected for the study. These horses were not wearing shoes and were exercised on a treadmill three times a week for four weeks.
• Each exercise session lasted between 10 and 14 minutes and included walking, trotting, cantering and, sometimes, galloping at 12.5 m/s.
• The research measured the proximal hoof circumference (PHC) and toe angle (TA) of each forelimb hoof weekly throughout this period. These were recorded using a flexible measuring tape and a hoof gauge respectively.
• Before the first exercise session and after the last one, strain gauges were used to measure the strain in the hoof wall at the toe and each quarter.

Research Findings

• The researchers observed that the strain on the hoof wall showed a consistent pattern of deformation across both forelimbs at all gaits.
• They found that the strain increased during the stance phase of the stride and was dependent on the site of the hoof where it was measured and the gait being used by the horse.
• The mean TA showed a significant increase over the course of the four weeks, but no significant change was observed in the PHC.
• No relationship was found between TA changes and hoof wall strains.

Research Conclusions

• The strain on the forelimb hoof wall in unshod horses was apparent, and the study concluded that this strain was affected by the site on the hoof and the type of gait used, but was not influenced by discrete changes in TA.
• There was no change noted in PHC in response to moderate regular exercise, implying that the intensity or frequency of the exercise sessions was not high enough to cause changes in hoof size.
• Significant changes in TA did not disrupt the consistent pattern of hoof loading recorded in the study, suggesting that horses can adjust their limb mechanics to maintain balance and stability despite alterations in TA.