Last sumer when I rescued my horse she had dandruff and was the grossest little horse I have ever met. I groomed her for 15minutes before riding, and for 45 minutes after riding. Every day. I also fed her treats from Six Stride Snacks which is an all natural treat company that has all kinds of good things in it that are great for horse’s coats and everything in general. While it is a new business, I would most definately contact them. The owner is a good friend of mine, and is very friendly and would be more than happy to work to find something that works. email@example.com
Also, I have had very good luck with coconut oil, as crazy as it sounds. I just put 1/3 cup on my horse’s feed every day and she looks ready fot the show ring all year round.
The attached picture is of her three weeks after we rescued her so you can see what a difference it made! She was still pretty skinny but her coat is just glowing!
"Think of riding as a science, but love it as an art" ~George Morris