If I separate my breeds can I put them together and ...

I have no experience with this, but I would think that seperating them and then putting them together may not be a great idea. We want to do the same thing, so next spring we are going to get pairs of the breeds we want and keep them seperate forever.

 

You can sure do it. They may fight as if they haven't met before, the pecking order is very important to them.

I move my flocks around several times a year, there's always some fighting, but never too bad.

 

Since they have already been together, but not sure.

 

It probably depends a lot on whether they can see each other when you separate them, but I've successfully merged new birds into a flock without the adjustment period where they could see each other through the wire and it hadn't been that big of a deal. There was a bit of pecking order establishment, but no one drew blood, so it worked fine for me. of course, i was adding hens and not roosters.