By restricting your dog from comming in contact with chicks/chickens you will always live in fear of what may happen if..
So (if possible) you can try teaching the dog how to behave around baby chicks so this doesnt potentially happen in the future?
I have 4 dogs and 4 cats and they do not touch baby chicks. My trick was I made them 'submissive' to the chick...if I just said NO! and defended the chick, then they would just go after it while I am not around...
(I would often let my chicks hop around the kitchen floor) what worked for me was anytime my pet would get 'too interested' in a chick I scruffed my pet and rolled them over on there backs (submissive position) and placed the chick on top of them and then said LEAVE IT. By putting the chick ON them and holding it there while (vocally) scolding, the CHICK was essentually defending itself and 'dominating them', and made the chick seem not so helpless, so they learned to respect the chick.
This worked for me...however I know my pets well and cannot guarentee this will work for others, it depends entirely on your pet and its breed and nature and how confident/comfortable you feel trying it and 'knowing' your pet. Obviously if you have an overactive 80# dog this may not be feasible or wise. My pets are very obedient in general and learn things quite fast. My pitbull treats baby things as if they were her very own.
I do not ever leave them absolutely alone with baby chicks, but if they were to be near them with me not around I am confident they will behave respectfully.
Good luck! please keep us updated on "sweet pea"