A bale feeder device for a mixer grinder vehicle includes an elongate conveyor and table structure which is mounted on the mixer grinder vehicle chassis. The conveyor and table structure may be positioned to discharge slabs of hay into the hammer mill of the mixer grinder vehicle to permit the hay to be chopped or ground into small pieces. A feed chute positions the hay bale on the conveyor and table structure to permit conveyor chains having teeth thereon to rip away portions of the bale. A slab feeder roll cooperates with the conveyor chains to convey the slabs of hay along the table where the hay is directed to the hammer mill by feed rolls.