I would be rather upset at the condition of my horse. The breeder is responsible for the mare while in his care. I would be extra cautious of where I put a mare in for breeding.
Just something I have come up with. I mix crisco shortening (stabilizer which helps keep wound clean, Olive Oil (healing) with tea trea oil and vitamin E and I make a paste out of it. It is so great, keeps the abrasion soft, tea tree helps with infection and Vit E is healing. The main thing is to keep it soft so that scabbing can be kept scraped off. No proud flesh which is really dried scabs. Extra flesh. I had a horse skin himself on his hind end, probably by slipping and sliding. Amazing how this mixture healed back the skin and hair. It need to grain in and that is where the descabbing comes in. Flesh needs to be pink to heal. I went through a deep wound with a filly who got attacked by cat. Vet told me to clean and irritate to keep that new flesh graining in. Two month process with her. What we learn with things that happen to our beloved four legged friends!