Feeding the young horse??

[Lyndseyclewis]

My thoroughbred x is 4 years old, 16hh (I think she has an inch to go)
Over the winter she has dropped quite a bit of weight due to poor grazing and poor Haylage (this last week she is refusing to eat it).
She has been out of work for 12 weeks due to respiratory problem, started riding her again last week very lightly, she was broken in in November and going very nicely until the time off.
I'm looking for a weight gaining feed without the fizz. Any experiences or advice would be great.
Am currently feeding her:
Hifi molasses free
Baileys everyday high fibre mix
Naf gp supplement

Did try her with fibre beet but she stuck her nose up at it.

 

[Nudibranch]

Personally I would use something like Suregrow for minerals and then just ad-lib, good quality haylege. A branded small bale one like Horsehage, etc, if local haylege is rubbish. You could add micronised linseed, unmolassed sugar beet (most will eat it eventually - build up from a small amount) or sunflower oil to help put weight on but good ad-lib forage would be the best way to do it.