We have all manner of dogs here, including trained gun dogs and other hunting dogs and also have free ranging chooks. The only ones that I wouldn't trust 100% are the terriers, but then I would trust them 100% with anything, once they get an idea into their heads, they are little b****rds!
My way of breaking a dog to anything, is to expose them to it lots, in a controlled situation, have them on a lead, and every time they look, pull, lunge at the chicken / sheep etc, give the lead a sharp tug and growl at them / tell them off. I do this lots until I can do the same without any lead, dog by side, walk through / near chooks and if they look / lunge etc get over the top of them, use body language and verbal tone to convince them that if they grab that bird they will get it bad.
Usually it doesn't need physical reprimand, but i've had a couple of dogs that in the end, it look a physical correction to put them right, some may not agree, but you need to know your dogs and know where the line is.