Hi
@Susanh8043. I have my horse on Vitamin E, although he's never had a blood test to prove he's deficient, I was just desperately searching for something to help his issues last winter when he had a horrible skin infection that wouldn't clear up. One of my Google searches threw up Vitamin E to support the immune system and when I read more about it I realised that my horse had a lot of the classic signs of Vitamin E deficiency. He has always been what even the vet called a 'summer horse', and prone to problems in winter. For instance, he had several episodes of seizing up after exercise. The worst episode he could barely move, the vet was absolutely convinced he was tying up and treated him accordingly (muscle relaxants and pain killers) but the blood results showed that he wasn't tying up at all. I always had to avoid putting cold water on his back after exercise and gave him a Danilon in his feed after any strenuous activity to stop his muscle cramps. He used to sometimes feel like he had the handbrake on when I was riding him and do funny little muscle twitches as though someone had poked him in the bum or he'd gone over a speed bump with one leg. He used to shake whenever I got the lorry out to go somewhere, presumably with excitement but everyone used to remark on it. He didn't lose a massive amount of weight, but he was always hard to keep weight on in winter and completely lost his 'bloom'.
We always knew he did well on grass (Vit E source) and in winter he gets little grazing, last winter barely any because of his skin and the need to keep his legs dry. He also has Cushings and so needs more support anyway.
I decided to give Vitamin E a go and so far (touch wood) the improvement has been remarkable. I started it back end of last winter and his skin infection cleared up, although it's impossible to say whether that was due to the Vit E, a change of topical ointment (I kept trying new ones) or just co-incidence. However all his muscle symptoms are much improved, no more shaking, no cramping, no need for a Danilon when we've been hunting etc. He is feeling fab at the moment and I'm just keeping everything crossed that it is due to the Vitamin E.
I have him on this one
https://www.saracenhorsefeeds.com/supplements/kerx-nano-e because it is supposed to be most rapidly available and I can adjust the dose according to workload. At the moment he's on 4,000 iu daily (more before and after a hard day), but I reduce that to 2,000 when he's on grass. I tried a cheaper powdered supplement but he came out in hives, although I tried a new fly spray at the time so not sure which was the culprit!
I've just seen
@Jessey's posted while I've been typing this, I was hoping she would reply as she is very knowledgeable about nutritional requirements and has given me lots of advice about Vitamin E.
I'd be very interested to hear what your vet recommends and what outcome it has. I hope your mare improves on the treatment and gets her appetite back. Out of interest, whereabouts in the world are you?