You can't help but feel sorry for them- that's how I always end up with a project or two.

I depends upon if there is something wrong with her other than just food (I agree, get the vet out). With your Idaho weather, winter is going to be very hard on her. Equine senior & lots of grass hay as it's easily digestible. Don't worm or vaccinate her until she is in a bit better weight and you know what's going on. Then one thing at a time with these guys. Mini's are susceptible to almost everything, so please put her in a separate area, even if it's just for 30 days.

Call Dr. Hanna Evergreen on this side:

(360) 794-8387

She can help you with actual good advise (as most vet's don't actually have experience badly emaciated horses). She helped with the really, really bad cases last year with SAFE seizure horses and I also used her on our rescues.