Hi all, newb here. Im so newb that i don't even have chickens yet. Before i get my chicks in a few weeks i am trying to learn as much as possible so i can be well prepared. I will be keeping them in an urban setting so its CRITICAL that i don't raise roosters. I know chicks can come pre sexed at as young as day olds and i would like to know how the experts do it, what do they look for? is there a site i can go to that explains this? i know for humans sex is determined long before conception, i know with leopard geckos incubation temps manipulate the gender ratio. (this is useful as females make less aggressive pets) When is sex determined in chickens, and can it be manipulated??