A system for feeding livestock with a liquid feed containing whole milk, wherein the system comprises the following: • a whole milk store which comprises a whole milk tank for receiving a stock of whole milk and which comprises a withdrawal line, • a preparation unit for preparing a liquid feed portion which comprises a whole milk supply line, a liquid feed portion container, and a dispensing line, • a connection line which connects the withdrawal line to the whole milk supply line, • a suction teat which is connected to the dispensing line, • a cleaning unit which comprises at least one cleaning agent container for receiving a cleaning agent and which comprises a cleaning agent supply apparatus, and • a controller which is designed to actuate the cleaning unit and the preparation unit to perform a cleaning process, characterized in that • the whole milk store comprises two whole milk tanks, wherein the withdrawal line comprises two withdrawal line sections which in each case comprise a discharge valve and are connected to one of the two whole milk tanks, • cleaning agent can be supplied from the at least one cleaning agent container to the two whole milk tanks by means of the cleaning agent supply apparatus, • the controller is designed to actuate the cleaning unit, the preparation unit, and the discharge valves to perform a cleaning process such that a cleaning liquid is conducted from one of the two whole milk tanks through the connection line and into the preparation unit, and wherein • the controller is designed to automatically carry out a cleaning process according to a schedule and (i) to specify a filling quantity (102, 106) in consideration of a predicted demand for one of the two whole milk tanks that is empty at a first cleaning time, such that said filling quantity is sufficient until a second cleaning time that follows on from the first cleaning time, and/or (ii) to specify a filling time, such that a whole milk store in one of the two whole milk tanks is available at the latest at the filling time when said one of two whole milk tanks is filled and before the other of the two whole milk tanks is empty. • a whole milk store which comprises a whole milk tank for receiving a stock of whole milk and which comprises a withdrawal line, • a preparation unit for preparing a liquid feed portion which comprises a whole milk supply line, a liquid feed portion container, and a dispensing line, • a connection line which connects the withdrawal line to the whole milk supply line, • a suction teat which is connected to the dispensing line, • a cleaning unit which comprises at least one cleaning agent container for receiving a cleaning agent and which comprises a cleaning agent supply apparatus, and • a controller which is designed to actuate the cleaning unit and the preparation unit to perform a cleaning process, characterized in that • the whole milk store comprises two whole milk tanks, wherein the withdrawal line comprises two withdrawal line sections which in each case comprise a discharge valve and are connected to one of the two whole milk tanks, • cleaning agent can be supplied from the at least one cleaning agent container to the two whole milk tanks by means of the cleaning agent supply apparatus, • the controller is designed to actuate the cleaning unit, the preparation unit, and the discharge valves to perform a cleaning process such that a cleaning liquid is conducted from one of the two whole milk tanks through the connection line and into the preparation unit, and wherein • the controller is designed to automatically carry out a cleaning process according to a schedule and (i) to specify a filling quantity (102, 106) in consideration of a predicted demand for one of the two whole milk tanks that is empty at a first cleaning time, such that said filling quantity is sufficient until a second cleaning time that follows on from the first cleaning time, and/or (ii) to specify a filling time, such that a whole milk store in one of the two whole milk tanks is available at the latest at the filling time when said one of two whole milk tanks is filled and before the other of the two whole milk tanks is empty.