Influence of different exercise regimes on the proximal hoof circumference in young Thoroughbred horses.

The research aims to examine the impact of various training routines on the shape of a young Thoroughbred racehorse’s hoof, particularly focusing on adjustments in the proximal hoof circumference. The findings demonstrate that the hoof circumference tends to decrease during the training periods and increase during the rest periods.

Objective

• The main objective of this study was to investigate the impact of training on the proximal hoof circumference in young Thoroughbred racehorses prepared for racing. The researchers aimed to shed light on the lack of information on normal exercise’s effect on hoof shape, a crucial aspect as most lameness in horses is connected to foot issues possibly associated with changes in hoof shape.

Methodology

• The study incorporated 37 young Thoroughbred racehorses.
• To measure the change in front hoof circumference (just below the coronary band), a measuring tape was employed weekly across all horses present at the stable.
• The majority of the horses undertook at least two training periods at the stable, each followed by resting periods on a paddock.
• The left proximal hoof circumference of 25 horses was measured three times in a random sequence on a single day for estimating the repeatability coefficient.

Results

• The results highlighted a common pattern of change—proximal hoof circumference decreased during the training periods and increased when the horses were rested.
• The reduction in circumference during the first training was -0.66 mm/week and -0.64 mm/week for the left and right, respectively. In the second training period, the reduction was -0.58 mm/week and -0.57 mm/week for the left and right.
• During the rest period, there was an increase in the circumference by 1.03 mm/week on the left and 1.12 mm/week on the right hoofs.
• The repeatability coefficient for the left circumference was calculated as 1.8 mm.

Conclusions

• The study concluded that race training resulted in a decrease in hoof circumference, which reversed when the horses were rested.
• Measuring the front hoof circumference is a simple method to assess changes in hoof shape and provides a means to investigate the relationship between specific training, hoof shape, and the horse’s soundness or health.