No, I haven't had chickens long at all, I'm just pointing out what others have said. If you haven't seen that thread I referenced, you should. It has a lot of great stuff in it.
Do roosters suddenly turn aggressive at a certain age? - Page 4
I have a dominique rooster that is two, raised by hand, played with all the time, feed him mealy worms. He comes running when he sees me. Then when I turn my back, bam, he attacks me. So I pick him up and give him the hold treatment. Kinda of time out for chickens. LOL. I hold him for about 4 or 5 minutes. Has not helped at all. He is a handsome boy that I payed a lot of money for, so I will tolerate it. He is my main breeder. And after breeding season he seems to settle down a bit. Having been raised on a large cattle farm, you never could trust a bull, that is just some of their natures.