Huh! My Arab is 26-1/2, I wonder if they're related
Triple Crown Senior worked really well for my fella but I also added in some equine rice bran and 1/2 measuring cup of straight alfalfa pellets.
"worked" being the operative because I took him off the TC Senior. I have four horses and four sets of health issues. At this moment they all eat different and I am trying to put an end to that - especially when I have to drive 38 miles to buy some of their "stuff"
1. The alfalfa pellets give my Arab the protein and amino acids he needs for muscle maintenance. You will know if you're feeding too much alfalfa if her urine develops a very strong ammonia odor. I buy Standlees at Tractor Supply.
2. If you can get Triple Crown Senior, it is a great feed. It is ok to add rice bran.
My Arab has a great shine to his coat; I hate having to take him off of it but he's going on the same diet my 25 yo TWH with Equine Metabolic Syndrome is on: Rice Bran and a Liquid Vitamin.
They are both hard keepers, the TWH now colics at the mere mention of the word, so the less I feed him and still get his nutrients in him, the better off he is.
2.1 Equine Rice Bran is 22% fat and provides a cool energy to the horse.
2.2 Beet pulp pellets should work if you don't want to feed rice bran.
Tractor Supply carries both.
3. I also feed Omega-3 Horseshine. My Arab is only 13.3H so he gets 3/4 cup daily, in two feedings.
If you've never blanketed your Arab, you may have to start, if she's outside on the really cold blustery days. A waterproof, winter-lined blanket will help her conserve calories
Hope this gives you some more ideas. There are a lot options out there but I am learning that "less is more" with the older crowd