Quail eat grains and insects in the wild, but coturnix aren't a good example of wild birds. They've been domesticated since the 1100s. For adult birds, you're looking for about 20-24% protein, and (@007Sean please correct me on these if I'm off since I'm still learning) about 1.5% lysine and about 1% methionine. For laying hens you want about 3.5% calcium or offer calcium on the side.
