Visual and morphometric description of feral horse hooves from Sable Island National Park Reserve.

Objective: To visually evaluate and morphometrically describe a sample of abnormal hooves from Sable Island horses that died between 2007 and 2013. Animal: Equine. Procedure: An opportunistic sample of 356 abnormal hooves from horses inhabiting Sable Island National Park Reserve (Canada) was collected postmortem between 2007 and 2013 from 101 Sable Island horses. These hooves were assessed for abnormalities in conformation through visual and morphometric evaluation. Results: On visual and morphometric evaluation, 100% of horses (101/101) had abnormal hoof conformation when compared to a domestic horse hoof model. Specific abnormalities from visual evaluation included long heels (85%); medial, lateral, and dorsal flares (45, 78, and 46% of horses, respectively); and cracking (62%). Specific abnormalities determined from morphometry of the hooves included contracted heels (87%), hoof imbalances including mediolateral imbalance (61%), and hoof length greater than width (100%). Conclusion: Sable Island horses had various hoof abnormalities such as hoof capsule flaring; long, contracted heels; and mediolateral imbalance. These abnormalities have been observed in other feral horse populations living on soft substrates. Given the potential impact of hoof abnormalities on the welfare status of the Sable Island horses, further studies are warranted, including estimation of the prevalence of hoof abnormalities and direct observation of horse gait and behavior. Clinical relevance: The significance of the hoof abnormalities for the health of the Sable Island horses is difficult to determine but the issue highlights the importance of further study to investigate the impact on the horses' welfare.