I am getting antsy to introduce my 25 8-week old pullets to the rest of the flock. How old should they be? I have 2 20-week old roos (HUGE boys) and 4 20-week old BR hens, as well as 2 20-week old batam cochins. My only concern is Belinda-the mean BR hen and Elvis, the OMG-HUGE BO roo. He's really nice but he is way to big to be getting up on even my BR hens....I dont want to think about the damage he'd do to an 8 wk old! So, how old should the lil ones be before I make the introductions?