Thrush

Also another concern I have. If you have a draft horse you might know that they tend to have extremely deep crevaces around there frog which easily get thrush. Sharubi gets thrush quite often and I hate it. I use Thrush Bustewr to treat it, but I can't find anything really good to prevent it. She also has a heal crack now which is worrying me. It's not getting any worse right now, but it's definatly not getting better. She has a dry, clean stall, so she probably aquires its form going out in a muddy paddock after it rains or something.
If anyone knows a really effective treatments for thrush please let me know!!