I use a high forage creep and get them going asap like my feeder is out now. The feed I have used is Rough and Ready from ADM and this year just from a cost factor I am using Creep Pasture Gest 14 B68 from Land 'O Lakes. They are both a pelleted complete feed that is meant to expand their guts and build frame while not adding to much condition early on so when I wean them they will "bloom" when I switch to a more energy diet. Works well for me. After weaning I am thinking about trying something like this:
860# cracked corn 420# whole oats 200# beet pulp 400# Grand 4-T-Fyer 120# molasses in a 2000 lb. mix and feed them hard for 60 days prior to sale is what I am thinking anyway! Hope this helps.