Abstract: A knock down salt and mineral feeder for cattle is formed of two oppositely facing sidewall subassemblies formed by vertical posts of different length, between which pasts span a trough sideboard. A side panel is factory preassembled to the trough sideboard and post. Each rear post bears a vertical mortise slot. The trough sideboard bears an inclined mortise slot. A horizontal mortise slot within the bottom of the trough sidewall extends from the inclined slot of the sideboard to the post vertical slot. A rear wall subassembly is formed by a back panel having a trough backboard fixed thereto bearing tenons on its end fitting within the vertical mortise slots of the rear posts. A horizontal mortise slot within the trough backboard is aligned with the horizontal mortise slots for the sidewall subassemblies. A roof subassembly is formed of a roof panel mounted via a pair of sideboards to the lateral sides of the roof panel.