The present invention provides improved chlortetracycline-containing animal feed compositions and processes and apparatuses for their preparation. The remaining portions of the trenches are then filled with a conductive material to form first and second field plates. A Sync Pulse cell at the receiving IC generates a sync pulse signal to the BSC of the receiving IC. The valve actuator can move a plurality of valves, when disposed therein, among an off position, a flush position, and a collection position. An actual converted EGR ratio is proportional to an intake-air oxygen concentration, and an actual converted EGR ratio and a target converted EGR ratio are calculated independently of a command injection amount.