Yeah I've inspected the whole fence line, but couldn't find anything of suspicion. It's electric fence all the way around, no hedges, no trees
yeah I think you might be right - the field has been fully inspected for other stuff and I think it must be another horses foot...I had a near identical one, saw it happen and it was a kick.. a nail pulled the sharper line and my best guess is the round edge of shoe scrapped the bigger bit off. if its any consolation, it healed super fast and only left a tiny scar!