Dogs with a prey drive do kill live stock. So many injure and kill chickens, sheep and other animals. Some even attack humans. You cant just say it’s the humans (boss) fault. The strong prey drive is in some dogs without training them for it.
Next an example, but things likes this happen all the time: My brother and my parents lived next to each other. My brother had a Bouvier and my mother had chickens. One day, out of the blue the dog jumped into the run and killed two chickens. Dogs are descendants of wolves and some are not fit to live freely amongst livestock or amongst people.
In England there are a few breeds that are not allowed for this reason.
https://www.gov.uk/control-dog-public/banned-dogs
Here we don’t have a list like this but plastic surgeons did make an appeal to our gov. a few months ago, because they see a lot of (unnecessary) damages from certain types of dogs.