I had friends who owned an N/H horse. They bought her from a family who had really young girls and they were showing her on the app circuit. She was a decent mare (soooo mare-y and my friends made it worse) but the fits...eek. If you've never seen an HYPP attack, I strongly urge you to do so. It's terrible. I only saw her go down a couple of times, but I also remember them having to get off her and walk her with Karo syrup a number of times, too. They did a lot of research and they were very diligent owners (they're the same ones who nursed their horse with a broken leg back to soundness, I think I've mentioned it a couple times here) and had a good vet. They also have kept her as a lifer. She was a great show mare and to them it was worth it.

I don't think I would ever buy an N/H horse. Plenty of good horses out there that I don't have to worry about them seizuring and collapsing.

ETA: Even if he's never shown any symptoms, I would educate yourself and take the precautions just in case so you do know how to deal with it when it happens.

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