Join Date: Oct 2007
Location: Alberta, Canada
• Horses: 0
As FehrGroundRanch said, it could be anything causing that. What I can guarantee you it isn't is good. It could be originating from his back, shoulder/hip, knee/hock, coffin bones, hooves, or anything in between.
If it's not too too bad, walk him around a bit and see if he if he'll walk out of it... if not, or if it persists, definitely call your vet. Or if you have a trainer, have him/her look at your horse.
Hope everything's ok:)
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