MTG if your willing to put up with the smokey smell works absolute wonders

BioMane supplement?

I had a friend whose horse had a bad mane and she roached it so it could grow out new.

This might not be a good option for you, but it may be something to consider. I don't know how much mane your horse has, but you could also try braiding it to protect the hair.

I have found Biotin capsules (opened and sprinkled into feed) work very well! I also like the Santa Fe conditioning spray. Highly recommend keeping the mane braided if at all possible.

mtg does smell like bacon lmao

but it does work great for growing hair

my boy had a disgusting short showjumper mane (which looked rank on him because he is a thick muscly dressage horse) so i added coconut oil to his food which he loved, and about 3 times a week i massaged castor oil into his mane and tail. Grown a ton in the past couple of months!

Try some linseed, might strengthen it. Also, is you massage the area it might help lol. Works for people so might work for horses >,>