Cleaning and disinfecting horse brushes are things that every horse owner is going to have to do at some point.
Cleaning your horse brushes is a fairly simple procedure. Your best bet is to use Dawn dish detergent. You can use any soap you have on hand if need be. You could even use your favorite horse shampoo.
Natural bristle brushes are more sensitive to being soaked for long periods of time. The wood and bristles are more easily damaged.
Cleaning horse brushes can be done routinely. How often to clean them will depend on how many horses you groom and how often a particular set of brushes are used.
Cleaning and disinfecting horse brushes is an easy enough task that should be worked into your normal stable routine at least once every year if not every six months.