Abstract: The feed mixing device of the present invention includes a sub-frame, a frame suspended on the sub-frame, and a polygonally-shaped drum rotatably mounted on the frame. A drive system is provided for rotating the drum and an auger assembly axially mounted within the drum. A hopper introduces feed into the drum while an adjustable discharge opening adjacent the end of the auger permits selective removal of feed from the drum. A plurality of rows of elongated mixing paddles are secured to the interior of the side wall of the drum such that the longitudinal axis of the paddles are angularly disposed with respect to the axis of rotation of the drum. The paddles within each row are staggered with respect to the paddles in adjacent rows. Convex, channel-shaped scoop blades are mounted to the rear wall of the drum and carry mixed feed to the auger as the drum rotates. A strain gauge is operatively connected to the suspended frame for sensing the displacement of the frame in response to loading of the drum.