What causes and how do you treat blocked milk duct and mastitis?

Mastitis is inflammation from injury or infection, what commercial operations do to prevent this is every they milk, they dip the teats in iodine and they also wipe them off and sterilize them before milking as well, there is no way to stop it from happening but that is one way to minimize it. To treat it, it depends on the severity of the injury. You could let the cow heal by its self or you can treat it with antibiotics.