An animal feeder includes a hopper above a shelf onto which feed can fall to be taken by the animal or dropped into a trough below the shelf. The height of the shelf is adjustable to change the width of the opening through which the feed passes to control feed rate. The shelf is carried on straps which extend along the end walls of the hopper and are movable by an adjustment linkage defined by a plate carried on the end wall and a manually adjustable lever mounted for pivotal movement on the plate. The plate has an arcuate outer edge which is serrated to define an arcuate row of saw teeth and the lever is formed by a flat of sheet material which lies in a plane parallel to and slides over the plate and includes a portion thereof which is bent out of a plane of the lever into the plane of the plate which is also serrated with a row of saw teeth shaped to mesh with the saw teeth of the arcuate portion. The portion of the lever is movable in a direction away from the plate a non-meshing position in which the lever is free to move around the pivot axis.