I" love" the they are just chickens. Well that dog of yours that I just shot was just a dog. You can get them for free on CL. shelters have so many that they have to put them down, even the young ones. Show ME the last time somebody offered free baby chicks in an AD.x2
However,I think all States/Territories/Protectorates allow one to retire any pred (domestic or wild) that is attacking a human. If the authorities HAVE to be called it is best to do it immediately and report a vicious dog (snapping/rushing humans- who were attempting to protect their poultry/children/disabled adults - not `just' attacking poultry) on one's property that had to be put down We've had good luck just letting everyone know that we keep poison bait out in woods for fox/coyote "gee, wouldn't want anything bad happening to that fine dog of yours...". There is really nothing they can say (check local regs on baiting for nuisance wildlife).. I always remain somewhat cheerful and exceedingly polite - particularly when inquiring after the dog owner's opinion on whether a loose dog represents nothing more than road kill waiting to happen.
Also, therapy/meds for PTSD following a dog attack can be very expensive to dog owner. Best strategy is to never give the dog owner an opportunity to conclude `they were just chickens' rather, keep them focused on observing `I'm being pretty stupid about dealing with the humans who happen to own the poultry'.