In general, all livestock used to produce organic milk must be maintained using the methods of organic farming as defined in the jurisdiction where the milk will be sold, and generally must be certified in order to be marketed as organic. In general, these laws require that livestock be allowed to graze on pasture, be fed organic certified feed (which may not include byproducts of animal slaughter), and that the animals not be treated with drugs (although it is also illegal to withhold necessary drugs from a sick animal in order to maintain that animal's organic status).