mixing new and old?

[buckinnuts]

I have some chicks that will be about 8-9 weeks old when I get some day olds in about 2 weeks . How long to keep seperated or will there be issues of aggressiveness
I know about the heat difference
but what else to be aware of
Thanks

 

[chicknhawaii]

What I've seen posted most often is a slow familiarization process is best where you put them in separate cages/coops where they can see one another. Gradually you can introduce them to one another face-to-face with supervision for a short time each day, lengthening the time if all is well. I think in general, when everyone's about the same size is when you can try to put them in the same coop. Good luck!

 

[Suess hens]

I have some 1.5 weekers that I took outside today into the yard where the "big" girls were free ranging. I figure if I start slow and watch for aggressiveness I will feel safer when I put them altogether. I am planning on moving the babies out when they are about 4 or 5 weeks...nights will be warmer then too. Oh and I have 7 week old and 2 10-week olds.