Both. Protein in the gravity feeders and corn in the spinners. Start the protein early spring and stop around October. Corn in the spinners year round. Protein can be pellets or natural (think roasted soybeans). Cottonseed is like steroids for antler growth but it requires a special feeder that is neither gravity nor spin feeder. All of this in conjunction with year round food plots. Of course a feral hog infestation will destroy all of this.