With funding provided by the Morris Animal Foundation, UC Davis Center for Equine Health and Merial, research into Hoof Wall Separation Syndrome in Connemara Ponies has been undertaken by Dr. Carrie Finno, Carly Stevens, and Dr. Danika Bannasch.
Looking for genetic cause of HWSS in ponies
Affected ponies can suffer severe pain despite careful management; their quality of life can diminish and euthanasia may be necessary.
Hoof Wall Separation Syndrome (HWSS) is an inherited condition seen in Connemara ponies and typified by the dorsal hoof wall splitting away from underlying structures. This hoof defect develops in young foals between one to six months of age.
The condition results in afflicted ponies having to support weight on the sole of the hoof instead of the dorsal hoof wall. Affected animals can become severely painful despite careful management; their quality of life can diminish and euthanasia may be necessary. Even if the condition is initially controllable, ponies may still develop laminitis over time.
HWSS is particularly troubling for the Connemara community because the parents of affected ponies are themselves completely unaffected. Although affected individuals do share common bloodlines, it is problematic to predict whether a particular breeding will produce a foal with unhealthy hooves.
Investigation into the underlying genetic cause of HWSS has the potential to inform these breeding decisions, and could also provide insight into the disease pathophysiology.
To investigate the underlying genetic cause of HWSS, a genome wide association study was performed and a strong association between disease status and polymorphisms in a two-megabase (Mb) region of the genome was observed.
Sequencing of candidate genes within this region is currently underway, and any functionally relevant genetic differences identified will be validated using a larger sample set. Consequently, researchers are still collecting DNA samples from both affected and unaffected Connemara ponies.
If you are interested in submitting a sample, please contact Carly Stevens (cstevens@ucdavis.edu) or Kartika Jayashankar (kjayashankar@ucdavis.edu) for more information.
Information for news report from UC Davis