Abstract: An animal in a pen is fed by a drop tube from a raised supply system to a position at or adjacent the floor or a trough at the floor. A spout at the bottom of the drop tube extends at an angle to the tube for discharging the feed in a direction to one side of the drop tube depending upon an angular orientation of the drop tube about a vertical axis of the drop tube. A clamp for attaching the drop tube to the wall of the pen includes co-operating indexing adjustment components including a stud mounted on the tube and grooves in the top surface of the clamping band which can be adjusted to provide a plurality of indexed angular orientations of the tube about the axis for locating the direction of discharge of the spout at specific indexed locations relative to the trough.