We feed medicated starter/grower to our chickens until 8 weeks, then starter/grower unmedicated until 10 weeks. Next is grower/finisher until 18 weeks. Then for layers its layer feed from then on. For roosters, we read to mix layer and scratch... We also heard that scratch is a good treat for chickens on cold winter nights to keep warm, so should we mix something else with layer for the roosters when it is hot summer days? Does the scratch give too much energy to already wound up roosters that seem to have fun ripping feathers out of each others necks? Help!!