I am going into winter for first time with small chicks that are not being reared by a hen. By the time they have full body feathers they will have to be outside to deal with our highly variable mid-Missouri winter. I would like to provide them with an energy dense diet, more so than what the typical carbohydrate dominated scratch diet. I have read on multiple threads that black oil sunflower seeds (BOSS) are suitable for adult chickens even with hulls on. How large will my chicks need to to handle the hulls? The BOSS will be mixed in to repressent only about 10 to 15% of the diet.