We got our first two chickens when my Rough Collie was only 8 months old. He has crazy prey drive, does not listen, and is the nuttiest thing. He is absolutely the antithesis of my last Smooth Collie who was all sense and protectiveness and response extrodinaire. Needless to say the two little Brahma qeens were protected scrupulously. They were contained and expenned and moved around in thier tractor. The Collie pup Rocket though would very often be found (along with my old, since passed, Newfy girl) lying next to wherever the chooks were enclosed.
When we got our chicks I put them in their brooder in the spare bedroom and closed the door- we had gotten our other pup a boy Newf, Diesel, by then and we have two house cats. But the very next morning first thing my Collie did was go and stand at that door, then I let him push past me to see what he'd do. He had to check on them and be in there with us as much as possible.
Our girls have an enclosed run and for a long time I didn't let either of the young dogs out when they were out of their run. But we hatched a few eggs and brought home a few young sebrights and a feral cat started thinking we were a fast food stop, so I thought it sure would be great if my silly Rocketdog would actually act like a Collie. So, I took him out on a leash.
Now, he'd also been "involved" in the brooding of the home hatched chicks, so I fed the girls some scratch and brought them in kinda close to see how Rocket would do and when any of the chicks we brooded in the house came up he didn't even look twice but the Sebrights he was really interested in. I gave him a correction and a "leave it these are family"- introduced them and darn it if that dog isn't the tireless defender of the flock! He is a Collie!He does give a laughing blast through them when I first let hem out sometimes but it is just his just out romp thing. He also loves chicken poop.
I still don't let Diesel out loose with the the Chicks because he is only 14 months and 150lbs or so, and is in the rubberheaded boy stage, he's like a train! and very goofy but I have high hopes for him, after all he is a Newf.