You just need to socialize the dog to the chicks, I own a RedBone CoonHound which isn't a bird dog by any means... but she has a huge prey drive for all animals under her size. I went through the same steps when introducing cats/kittens. First you need to have some form of control until the dog will operate under your rules when it comes to the chickens. I started will bulletproofing my "wait" "leave it" and "gentle" commands, I use "gentle" when I introduce her to children, new animals and when handing her food to tell her to move slowly and careful of my fingers. I had adult hens before any chicks, chicks are a huge advantage for you, let your dog sniff them through a kennel or on a leash that is tied up (this will help lowering the curiosity) and gradually your dogs will be less concerned about the chicks over time. When the chicks are old enough to move outside you may choose to teach your dog how to behave around the chickens when they are loose, leash you dog and run him/her through commands to improve the focus and lower the excitement, I just taught my dog to completely ignore the chickens, not to be friendly or watch over them, just ignore them like they don't exist. So you will start telling the dog to leave it every time you pass a chicken, the dog may still react when the birds flap around or make noise so just keeping working on "leave it" until it goes away.
