What Can I Give Following 2 Months of Antibiotics?

[Skips11]

As subject - horse has been on various antibiotics orally and intravenously as well as bute and steroids on and off for around 2 months. Finally got the all clear and would like to help her insides as much as possible after such a long period on various drugs. She seems a bit girthy (nothing close to how she was when she had ulcers) so I am keen to give her something to help.
She has always been on Feedmark Ultimate Ease which contains per/pro-biotics but wondering if I should swap that or add anything more suitable?

 

[ycbm]

My vet told me to feed natural bio (live) yoghurt, though I think there might be better things around these days.
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