Hello,
I had trouble with my barefoot horse on alfalfa, it tended to make his white line open up and become prone to infection, I saw a marked improvement within weeks of changing his diet - the white line closed up and I've gone from discinfecting his feet twice a week, to maybe only once a...
I don't use one with my bitted bridle (I jump in a Dr Cook bitless bridle so use one then). The main reason for me is simply because I hate tack cleaning, so the less he has, the less I have to clean!
Never had any issues not using one.