Hi Nicolle,
From your notes, it appears that her temperature yesterday was still considerably elevated.  Is that still the case today?  Has she shown more interest in eating?  I use a lot of soaked Timothy Balance cubes and they are great for adding weight but she obviously needs to eat them to get that benefit.  They also add lots of water.  I soak my hay for some of my guys in summer to make sure they get enough water.  Added salt will help that too.  Beet pulp, as Nancy said, is great for adding weight as well.  I always rinse, soak and rinse it until the water is clear to remove processing iron.  

When we need to counsel someone on adding weight to their horse, the horse is most often PPID and we find increasing the pergolide dose can help with that.  Elsa does not appear to be PPID so our recommended pergolide will not help her.
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