wobbles

yes it's quite normal. When I first saw a horse do this I was a student and supposed to be watching the horse and documenting any abnormal possible neurological signs. Even though I've had horses all my life I could swear I'd never seen it before and I thought it was wierd, but the professors all laughed at me because it's normal and they thought all horses did it. So, I reckon some do and some don't. I still think it looks wierd but I'm not bothered about it.

Now if she was groaning or grunting as well, then that's a different matter!
 
not just mares

My 29 year old gelding does this too. I figure his back is probably less supple than it was, but he still needs to 'assume the position' somehow. So he stands on tip toes. The worrying thing is then when he decides to lift a front foot up (for whatever reason) as well - terrifying but somehow he still stands up !
 
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