little chicks adding 17 week old hens?

I recommend NOT introducing them for a good while yet - like until the youngsters are fully feathered (4-6 weeks). The hens will be merciless on the little ones if done too early.

 

Ditto, it'll be heartbreaking if you try to mix them now. I'd even try to wait until they're all roughly the same size if that's a possibility. Good luck.
Nikki

 

What you need is a grow out pen for the youngest birds alongside the older birds. Once they are old enough to leave the brooder you can put them in their pen. This allows the older birds time to get used to them before you put them together. My chicks go out to their coop/pen at 5 weeks of age and stay there until they are about 15 weeks old. They share a fence line. By the time I let them out with the older girls pecking order scuffles are extremely minor.

If you try to integrate to fast, or when chicks are too young, the results can be terrible, youngsters can be killed. Chickens really are ruthless and they do NOT take to new birds easily. Sometimes if you try to go to fast the older birds get it in their heads to attack and drive off the new birds and sometimes they just don't get over it. Makes getting them integrated very stressful and difficult for everyone involved, including you!

 

I was going to say what cafarmgirl said. Most people wait until the younger birds are the same size...there are varying methods of introduction but I plan to use this one.