I ordered from a hatchery, 5 buff girls and 5 australorp girls. I also ordered 20 mystery chicks. With my mystery chicks I received 10 that I believe are Dominique. ...they have the striping and what looks like a rose comb. I noticed that one chick is larger, lighter in color and its comb is bumpier than the others. Does this mean that it could be a roo? Can you identify the difference between the girls and boys by their combs at 6 weeks old?